National Guidelines for Human Exposure to Radiofrequency … · 2015. 4. 23. · National Guidelines for Human Exposure to Radiofrequency Electromagnetic Fields Page 6 of 76 This

National Guidelines for Human Exposure to Radiofrequency Electromagnetic Fields

November 2009


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This publication is a translation. In case of divergence, the original Arabic text shall prevail.

Contents

1 PRELIMINARY AND GENERAL ................................................................................. 5

1.1 CITATION ................................................................................................................................... 5

1.2 ORIGIN AND STATUS OF THE NATIONAL GUIDELINES .................................................. 5

1.3 PURPOSE ..................................................................................................................................... 5

1.4 SCOPE AND APPLICATION ..................................................................................................... 6

1.5 TERMS AND DEFINITIONS...................................................................................................... 7

1.6 ACRONYMS AND SYMBOLS ................................................................................................ 11

1.7 INTERPRETATION .................................................................................................................. 13

1.8 REFERENCES ........................................................................................................................... 13

2 EXPOSURE LIMITS ..................................................................................................... 15

2.1 GENERAL.................................................................................................................................. 15

2.2 CLASSIFICATION OF EXPOSURE LIMITS .......................................................................... 15

2.3 BASIC RESTRICTIONS ........................................................................................................... 17

2.4 REFERENCE LEVELS .............................................................................................................. 20

2.5 SIMULTANEOUS EXPOSURE TO MULTIPLE FREQUENCY FIELDS .............................. 24

3 COMPLIANCE OF MOBILE OR PORTABLE RADIO DEVICES .... .................... 27

3.1 PARTIES RESPONSIBLE FOR COMPLIANCE ..................................................................... 27

3.2 COMPLIANCE OBLIGATIONS OF RESPONSIBLE PARTIES ............................................ 28

3.3 COMPLIANCE ASSESSMENTS .............................................................................................. 30

4 COMPLIANCE REQUIREMENTS FOR FIXED RF SOURCES ...... ...................... 33

4.1 NOMINATION OF COMPLIANCE SITES .............................................................................. 33

4.2 PARTIES RESPONSIBLE FOR COMPLIANCE ..................................................................... 33

4.3 OBLIGATIONS OF RADIO LICENSEES ................................................................................ 34

4.4 OBLIGATIONS OF PROPERTY OWNERS ............................................................................ 35

4.5 COMPLIANCE ASSESSMENTS .............................................................................................. 36

4.6 REQUIREMENTS FOR COMPLIANCE .................................................................................. 36


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5 ENFORCEMENT ........................................................................................................... 37

5.1 ENFORCEMENT POWERS OF THE CITC ............................................................................. 37

5.2 VERIFICATION OF ASSESSMENTS ...................................................................................... 37

6 DISTRIBUTION OF COMPLIANCE DOCUMENTATION .......... .......................... 39

7 VIOLATIONS ................................................................................................................. 39

8 ENTRY INTO FORCE .................................................................................................. 39

SCHEDULE 1 – DECLARATION OF CONFORMITY ............ ........................................ 40

SCHEDULE 2 – COMPLIANCE DOCUMENTATION ............. ....................................... 41

S2.1 RF CONTROL DOCUMENT REQUIREMENTS .................................................................... 41

S2.2 SITE COMPLIANCE CERTIFICATE REQUIREMENTS ....................................................... 42

S2.3 SITE IDENTIFICATION CODE ............................................................................................... 42

S2.4 GRAPHICAL DEPICTION OF EXCLUSION ZONES ............................................................ 42

ANNEX 1 – EXAMPLE ADVISORY TEXT FOR RF TRAINED WORK ER MOBILE OR PORTABLE RADIO DEVICES ............................................................................ 43

ANNEX 2 – DEVELOPMENT OF AN RF SAFETY PROGRAM ..... ............................... 44

A2.1 GENERAL ................................................................................................................................ 44

A2.2 ROLES AND RESPONSIBILITIES ......................................................................................... 44

A2.3 SAFETY CONTROLS .............................................................................................................. 45

A2.4 TRAINING ................................................................................................................................ 48

A2.5 PERSONAL RF MONITORS ...................................................................................................... 49

A2.6 RF PROTECTIVE CLOTHING ................................................................................................... 49

A2.7 RF OVER EXPOSURE INCIDENTS .......................................................................................... 49

A2.8 IDENTIFICATION OF RF EXCLUSION ZONES ..................................................................... 50

ANNEX 3 – RECOMMENDED RF SAFETY SIGNAGE .................................................. 51

A3.1 TYPE AND NATURE OF RF SAFETY SIGNS .................................................................... 51

A3.2 RF EXPOSURE AWARENESS SIGNS ................................................................................. 52


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ANNEX 4 – RECOMMENDED KEY LEARNING OUTCOMES FOR COMPREHENSIVE RF SAFETY AWARENESS TRAINING ........ ........................ 55

ANNEX 5 – WRITTEN RF SAFETY INFORMATION PROVIDED W ITH A MOBILE OR PORTABLE RADIO DEVICE ............................................................................... 56

ANNEX 6 – TECHNICAL GUIDELINES AND SAFE VERTICAL AN D HORIZONTAL DISTANCES FOR THE INSTALLATION OF BASE S TATION ANTENNAS .................................................................................................................... 57

A6.1 OBJECTIVE ............................................................................................................................ 57

A6.2 SCOPE ..................................................................................................................................... 57

A6.3 DEFINITIONS ........................................................................................................................ 57

A6.4 INTRODUCTION ................................................................................................................... 57

A6.5 MACRO BTS SITES ............................................................................................................... 58

A6.6 INDOOR AND OUTDOOR MICRO CELLS......................................................................... 69

A6.7 DIGITAL DATA TECHNOLOGY: WI-MAX ....................................................................... 73

A6.8 ASSESSMENT OF OTHER RF SOURCES ........................................................................... 76


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1 Preliminary and General

1.1 Citation This document may be cited as the National Guidelines for Human Exposure to Radiofrequency Electromagnetic Fields. Within this document it will be referred to as the National Guidelines.

1.2 Origin and status of the National Guidelines Pursuant to the Telecommunications Act, its Bylaw and the Ordinance establishing, the Communications and Information Technology Commission (CITC), the CITC is the entity authorized to regulate the Communication and Information Technology (CIT) sector in the Kingdom. In accordance with Chapter 12, Article 89, of the Bylaw relating to the Telecommunications Act, the CITC may prescribe technical standards in respect of telecommunications equipment and shall publish such technical standards; it may also develop, administer and enforce national guidelines. Consequently, the CITC has issued the National Guidelines to be enforced within the Kingdom. Compliance measures will be administered and enforced by the CITC.

1.3 Purpose The purpose of the National Guidelines is to establish technical regulatory practices for limiting human exposure to radiofrequency (RF) electromagnetic fields (EMF) to protect against known adverse health effects from installations or devices emitting RF fields.


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1.4 Scope and Application The National Guidelines establish minimum requirements for the protection of the public and workers from risks to their health arising or likely to arise from their exposure to RF in the frequency range 3 kHz to 300 GHz. The National Guidelines apply to RF exposures from fixed RF sources and installations that fall within the scope of the Act and Bylaws. Examples include (but are not restricted to) fixed RF sources associated with the following radio telecommunications and broadcast technologies:

a) Mobile telephone networks (e.g. GSM, 2G, GSM-R, 3G and Beyond 3G); b) Wireless networks (e.g. Wi-Fi and Wi-Max); c) UHF communication links; d) Microwave communication links; e) Millimetre wave communication links; f) Paging systems; g) Commercial radiocommunication networks and Trunking systems (e.g. the iDEN

system and Tetra); h) Emergency service communications (fire, police, ambulance, maritime); i) HF communications; j) Radio broadcast infrastructure (TV, AM/FM radio) for both analogue and digital

services including DAB and DVB; k) Terrestrial satellite stations including VSAT and internet connections; l) Amateur radio and CB; m) In building radio systems.

The National Guidelines also apply to RF exposures from mobile or portable radio devices that fall within the scope of the Act and Bylaws. Examples include (but are not restricted to) mobile phones, two-way radios (walkie-talkies), wireless microphones, portable Bluetooth devices, cordless phones, iDEN handsets and GMPCS terminals. The National Guidelines do not apply to the following:

a) RF exposure of patients undergoing diagnosis or treatment under medical supervision b) Use of RF by the Military c) RF exposure from radars d) Electromagnetic compatibility (EMC) of devices e) RF exposure from domestic RF heating appliances such as microwave ovens f) RF exposure from industrial uses of RF for heating, drying or welding g) Accidental ignition of flammable gases or explosives from RF exposures


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1.5 Terms and Definitions Adverse health effect: A biological effect characterised by a harmful change in health. Subjective changes in feelings of well being that result from anxiety about RF exposure or visual or psychological impacts of RF infrastructure, which are not directly related to RF exposure, are not considered to be adverse health effects within the context of these National Guidelines. Antenna: A device that serves as a transducer between a guided wave (e.g. coaxial cable) and a free space wave, or vice versa. It can be used to emit or receive a radio signal. In the National Guidelines, the term antenna is used only for emitting antennas. Antenna Gain: The ratio of the radiation intensity in a given direction to the radiation intensity that would be obtained if the power accepted by the antenna were radiated isotropically. Assessment: The determination of compliance with the public or occupational limits of the National Guidelines (refer definition below for public and occupational limits). Basic restrictions: The mandatory limiting values for human RF exposure expressed in metrics that closely match the biophysical interaction mechanisms of the known adverse health effects. Depending on the frequency of exposure, the metrics used to specify basic restrictions are: current density (J), specific absorption rate (SAR), incident power flux density (Sinc), and specific absorption (SA). Compliance: Conformity with the relevant requirements of the National Guidelines. Compliance boundary: A nominated boundary around a fixed RF source or a mobile or portable radio device that encloses the public and/or occupational exclusion zone (refer definition). Compliance site: A nominated area that incorporates both the public exclusion zone and restricted access areas associated with one or several fixed RF sources. Contact current: The rms magnitude (IC ) of RF current flowing through a biological medium (typically the wrist) when making point contact (e.g. fingertip) with an RF energised surface. It is expressed in units of mA. Current density: The magnitude (J) of a vector (J) for which the integral over a given surface is equal to the rms current flowing through the surface. Current density is expressed in units of rms A/m². It may be derived from the internal electric field strength (Eint in rms V/m) and the electrical conductivity of the medium (σ in S/m) using equation J = σ Eint Current probe: A clamp-on ‘loop’ current transformer for measuring current through the ankle or wrist. Decibel (dB): a logarithmic unit of measurement that expresses the power magnitude of an RF exposure quantity relative to a specified level. Since it expresses a ratio of two (same unit) quantities, it is dimensionless.


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If L represents the ratio of an RF exposure value P1 to another value P0, then the ratio expressed in decibels (LdB) is calculated using the following equations:

=

0

110log20

P

PLdB for P = E, H, IC, IL or J

=

0

110log10

P

PLdB for P = E², H², IC², IL², J², Seq, Sinc, SAR and SA

In the National Guidelines, the dB unit is used to express the upper bound (see definition) of an RF exposure evaluation relative to the best (i.e. most likely) estimate of the evaluation. Electric field: A region associated with a distribution of electric forces acting upon electric charges. Electric field strength: The rms magnitude (E) of the electric field vector (E) expressed in units of V/m. Electromagnetic field: A time and space varying field associated with electric and magnetic forces on electric charges as described by Maxwell’s equations. It can be characterised at any instant by electric (E) and magnetic (H) field vectors. Equivalent plane wave power flux density (Seq): An expression of electric or magnetic field strength in the units of power flux density (W/m²) assuming plane wave conditions. For electric field strength (E), it is calculated as: Seq = E ²/377 For magnetic field strength (H), it is calculated as: Seq = 377 × H ² Equivalent isotropic radiated power: The product of the power supplied to the antenna and its gain in a given direction relative to an isotropic antenna. Equivalent radiated power: The product of the power supplied to the antenna and its gain in a given direction relative to a half wave dipole. Evaluation: Determination of RF exposure levels by measurement or calculation. Exposure: In the context of this document, exposure of persons to electric, magnetic or electromagnetic fields or to induced and contact currents other than those originating from physiological processes in the body and other natural phenomena. RF exposure induces electric currents and electric fields inside a person; these are limited by the basic restrictions of the National Guidelines. Fixed RF source: A source of RF that is established for use in a fixed location and which falls within the scope of the National Guidelines. Fixed RF sources may include intentional radiators (e.g. base station antennas) as well as sources of unintentional RF exposure (e.g. leaky transmitter cabinets and transmission line infrastructure). Incident power flux density: The power flux density of the RF exposure that is incident on the surface of the body (Sinc). It does not include the contribution of reflected RF from the surface of the body. Instantaneous: Averaged over a time period of 0.2 sec.


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Integral antenna: An antenna that is: a) permanently attached to equipment; or b) intended for direct attachment to a fixed connector on equipment, without the use of

an external cable. Internal electric field strength: The electric field strength (Eint) induced inside a human body by RF exposure. Limb current: The rms magnitude (IL ) of RF current flowing in a wrist or ankle that has been induced by an RF exposure. It is expressed in units of mA. Localized SAR: The SAR averaged over any 10g of tissue in the shape of a cube. Lower bound: The lower bound of the 80% confidence interval (80% CI) relative to the best (i.e. most likely) estimate of an RF exposure evaluation expressed in dB units. The uncertainty calculations for determining the lower bound should be conducted in accordance with the requirements of the ISO Guide to the Expression of Uncertainty in Measurement. Magnetic field: A region associated with forces acting upon ferromagnetic particles or moving electric charges. Magnetic field strength: The rms magnitude (H) of the magnetic field vector (H) expressed in units of A/m. Microwave hearing effect: An RF bioeffect associated with pulsed RF exposures of the head. It occurs when energy absorbed in the head from strong RF pulses causes sudden thermo-elastic expansion of tissues resulting in mechanical acoustic vibrations that travel through the head to the cochlea of the inner ear. It may be perceived as a buzzing, clicking or hissing sound depending on the RF pulse modulation characteristics and is most commonly associated with high power radar exposures. It can generally only be perceived in very quiet environments. Mobile or portable radio device: A radiocommunications transmitter that is established for use:

a) in motion, on land, water or in the air, or b) in a stationary position at unspecified points on land, water or in the air

Examples of such devices include mobile phones, wireless modems and vehicle mounted radio communication systems. Occupational limits: Occupational limits are provided for the basic restrictions and reference levels which shall apply to the exposure of designated RF trained workers (see definition) who have been formally identified as such under a workplace RF safety program. The basic restrictions and reference levels are defined in section 2 of the National Guidelines. Occupational exclusion zone: An area where RF exposures have been assessed to exceed the Occupational limits. Pinna: The largely cartilaginous projecting portion of the outer ear consisting of the helix, lobule and anti-helix.


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Power flux density: The magnitude (S) of the time average Poynting vector (S). It represents the rate of flow of RF energy through a unit area normal to the direction of the wave propagation, and is expressed in units of W/m². It can be calculated at any point in space as the real part of the vector cross product (ℜ ) of the rms vector phasor electric field (ES) and

the complex complement of the rms vector phasor magnetic field (HS*): { }∗×ℜ= SS HES

Poynting vector: The vector cross product (S) of the electric (E) and magnetic (H) field:

S = E × H Property owner: The owner of any property (as specified in the land titles) that contains a fixed RF source. Public limits: Public limits are provided for the basic restrictions and reference levels which shall apply to:

a) RF exposure to all persons, except RF trained workers; b) All mobile or portable radio devices that are certified not to exceed the public limit.

(e.g. mobile phones, wireless modems, Wi-Max and Wi-Fi peripherals, cordless handsets).

The basic restrictions and reference levels are defined in section 2 of the National Guidelines. Public exclusion zone: An area where RF exposures have been assessed to exceed the Public limits, but not the Occupational limits. Radiofrequency: A frequency of electromagnetic field oscillations that is useful for radio transmission and which for the purpose of the National Guidelines extends between 3 kHz and 300 GHz. Reference levels: Practical exposure levels derived from the basic restrictions that may be used as a simpler, but more conservative, alternative approach for determining compliance with the basic restrictions. Only when the reference level is exceeded should a determination of the basic restrictions be made, since exceeding the reference level does not necessarily mean that the basic restriction has been exceeded. RF emitter: A fixed, mobile or portable RF source. RF Exposure meter: An RF survey instrument for measuring ambient electric or magnetic field strengths. RF personal monitor: An RF monitoring device carried on a person that is designed to alert the user when ambient E or H field exposures exceed the corresponding reference levels. RF safety program (RFSP): An organised system of policies, procedures, practices and plans designed to protect against hazards associated with RF fields, contact voltage, and contact and induced currents. RFSP’s should be documented in writing. RF trained worker: A person who:

a) is aged 16 years or older, and; b) is potentially RF exposed above the Public limits as a consequence of paid or

volunteer work duties, and; c) attends an RF safety program, and; d) is trained in safe RF work practices, and;


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e) has been medically assessed for fitness to work at RF exposures up to the occupational limits.

Risk: The likelihood or probability that a person will be harmed by a particular hazard. Root mean square (rms): The square root of the mean of the square of a time variant function, F(t), over a specified time period from t1 to t2. It is derived by first squaring the function and then determining the mean value of the squares obtained, and taking the square root of that

mean value, i.e. Frms =F(t)[ ]2

dt t1

t2∫t2 − t1

Specific absorption (SA): The energy absorbed per unit mass of biological tissue during an RF pulse. It is expressed in units of joule per kilogram (J/kg). SA is the time integral of the specific RF energy absorption rate during a pulse. Specific absorption rate (SAR): The rate at which RF energy is absorbed in body tissues expressed in units of W/kg. It may be calculated at any point in the body from Eint (rms V/m)

by the following relation: SAR=σ Eint( )2

ρ where σ is the electrical conductivity (S/m) and ρ

is the mass density (kg/m³) of the tissue. Transmission losses: A general term for the reduction of power in a transmitted radio signal resulting from any effects such as feeder/cable attenuation. Upper bound: The upper bound of the 80% confidence interval (80% CI) relative to the best (i.e. most likely) estimate of an RF exposure evaluation expressed in dB units. The uncertainty calculations for determining the upper bound should be conducted in accordance with the requirements of the ISO Guide to the Expression of Uncertainty in Measurement. Whole body average SAR: The SAR averaged over the entire body in units of W/kg. It is obtained by dividing the total RF power (W) absorbed in the body by the total body mass (kg).

1.6 Acronyms and Symbols 2G/3G Second and third generation digital mobile phone standards 80% CI 80% confidence interval of the uncertainty for an RF exposure

evaluation BTS Base Transmitter Station CB Citizen Band radio CITC Communications and Information Technology Commission for the

Kingdom of Saudi Arabia CT0, CT1, CT2, CT3 Cordless phone telecommunication standards DAB Digital audio broadcasting DAS Distributed Antenna System DECT Digital Enhanced Cordless Telecommunications standard DoC Declaration of Conformity (see Schedule 1) DVB Digital video broadcasting E Electric field vector E Electric field strength (see definition).


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Eint Internal electric field vector Eint Internal electric field strength (see definition) EMF Electromagnetic fields (see definition) EIRP Equivalent isotropic radiated power (see definition) ERP Equivalent radiated power (see definition) GMPCS Global Mobile Personal Communications by Satellite GPS Global Positioning System GSM The Global System for Mobile communications GSM-R The Global System for Mobile communications-Railways H Magnetic field vector H Magnetic field strength (see definition) HF High Frequency – 3 MHz to 30 MHz ICES / IEEE International Committee on Electromagnetic Safety, of the Institute

of Electrical and Electronics Engineers ICNIRP International Commission on Non-Ionizing Radiation Protection iDen Integrated Digital Enhanced Network IEC International Electrotechnical Commission IC Contact current (see definition) IL Limb current (see definition) J Current density vector J Internal current density (see definition) KSA Kingdom of Saudi Arabia MF Medium Frequency – 300 kHz to 3 MHz OH&S Occupational health and safety PHS Personal Handphone System RF Radiofrequency (see definition) RFCD RF control document (see Schedule 2) rms Root mean square (see definition) S Power flux density (see definition) Sinc Incident power flux density on the body (see definition) Seq Equivalent plane wave power flux density (see definition) SA Specific Absorption (see definition) SAR Specific Absorption Rate (see definition) Tetra Terrestrial Trunked Radio UHF Ultra High Frequency – 300 MHz to 3 GHz UMTS Universal Mobile Telecommunications System VHF Very High Frequency – 30 MHz to 300 MHz VSAT Very Small Aperture Terminal WBA SAR Whole body average SAR (see definition) WHO World Health Organization Wi-Fi Wireless Fidelity Wi-Max Worldwide Interoperability for Microwave Access


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1.7 Interpretation In interpreting the provisions of these National Guidelines, the words ‘shall’ and ‘should’ have particular meanings. The presence of the word ‘shall’ indicates that the requirement to which it refers is mandatory. The presence of the word ‘should’ indicates a recommendation – i.e., a requirement that is to be applied as far as is practicable. Schedules to the National Guidelines form an integral part of the National Guidelines. Annexes to the National Guidelines provide information supplementary to the requirements embodied in the National Guidelines. Annexes provide material that will help in interpretation of the National Guidelines.

1.8 References COMAR (2002) IEEE Committee on Man and Radiation. Medical aspects of radiofrequency

radiation overexposure. Health Physics, vol. 82, no. 3, pp. 387-391. ICNIRP 1998, ‘Guidelines for limiting exposure to time-varying electric, magnetic, and

electromagnetic fields (up to 300 GHz)’, Health Physics, vol. 74, no. 4, pp. 494-522. IEC 62311:2007 standard, Assessment of electronic and electrical equipment related to human

exposure restrictions for electromagnetic fields (0 Hz – 300 GHz), The International Electrotechnical Commission, Geneva.

IEC 62209-1:2005 standard, Human exposure to radio frequency fields from hand-held and

body-mounted wireless communication devices - Human models, instrumentation, and procedures - Part 1: Procedure to determine the specific absorption rate (SAR) for hand-held devices used in close proximity to the ear (frequency range of 300 MHz to 3 GHz), The International Electrotechnical Commission, Geneva.

IEC, 62209-2 standard, Human exposure to radio frequency fields from hand-held and body-

mounted wireless communication devices - Human models, instrumentation, and procedures Part 2: Procedure to determine the Specific Absorption Rate (SAR) in the head and body for 30 MHz to 6 GHz Handheld and Body-Mounted Devices used in close proximity to the Body, The International Electrotechnical Commission, Geneva.

IEC 62479 standard, Assessment of the compliance of low power electronic and electrical

apparatus with the basic restrictions related to human exposure to electromagnetic fields (10 MHz - 300 GHz). The International Electrotechnical Commission, Geneva.

IEEE C95.1- 2005 standard, IEEE Standard for Safety Levels with Respect to Human

Exposure to Radio Frequency Electromagnetic Fields, 3kHz – 300GHz, The Institute of Electrical and Electronics Engineers, International Committee on Electromagnetic Safety, New York.

IEEE C95.2- 1999(R2005) standard, IEEE Standard for Radio Frequency Energy and current

flow Symbols, The Institute of Electrical and Electronics Engineers, International Committee on Electromagnetic Safety, New York.


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IEEE C95.3- 2002(R2007) standard, IEEE Recommended Practice for Measurements and Computations of Radio frequency Electromagnetic Fields With Respect to Human exposure to Such Fields, 100 kHz – 300 GHz, The Institute of Electrical and Electronics Engineers, International Committee on Electromagnetic Safety, New York.

IEEE C95.7- 2005 standard, IEEE Recommended Practice for Radio Frequency Safety

Programs, 3 kHz to 300 GHz, The Institute of Electrical and Electronics Engineers, International Committee on Electromagnetic Safety, New York.

Interconnection Guidelines, Communications and Information Commission (CITC). Available from CITC web site: www.citc.gov.sa International EMF Dosimetry Handbook, Guidelines for the RF exposure assessment of

metallic implants, Anderson, V & McIntosh, R 2006. http://www.emfdosimetry.org/ ISO/IEC 17020:1998 standard, General criteria for the operation of various types of bodies

performing inspection, The International Standards Organisation and The International Electrotechnical Commission, Geneva.

ISO/IEC 17025:2005 standard, General requirements for the competence of testing and

calibration laboratories, The International Standards Organisation and The International Electrotechnical Commission, Geneva.

ISO/IEC Guide:1995, ISO Guide to the Expression of Uncertainty in Measurement, The

International Standards Organisation and The International Electrotechnical Commission, Geneva. (Known also as the ISO GUM)

ITU-T K.61-2008, Recommendation ITU-T K.61. Guidance on measurement and numerical

prediction of electromagnetic fields for compliance with human exposure limits for telecommunication installations. Telecommunication Standardization Sector of ITU.

World Health Organization Website: http://www.who.int/peh-emf/en/


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2 Exposure Limits

2.1 General The National Guidelines provide protection against established adverse health effects by prescribing safe limits on human RF exposure. Due to the complex nature of RF absorption in the body, its dependence of the RF frequency and the various biophysical mechanisms, the RF exposure limits in the National Guidelines are defined using a number of different metrics. These metrics are divided into two types, basic restrictions and reference levels, with public and occupational limits that apply to different circumstances of exposure. The exposure limits in the National Guidelines are generally consistent with the basic restrictions and reference levels recommended by the International Commission on Non-Ionizing Radiation Protection (ICNIRP, 1998).

2.2 Classification of exposure limits

2.2.1 Basic Restrictions and Reference Levels The basic restrictions of the National Guidelines are mandatory limits on human exposure to RF. Depending on the frequency of RF exposure, the physical metrics used to specify the basic restrictions are current density (J), specific absorption rate (SAR), specific absorption (SA) and incident power flux density (Sinc). Separate basic restrictions are specified for SAR averaged over the whole body (WBA SAR) or averaged over small regions of body tissue (localized SAR). The basic restrictions are specified in metrics that are often difficult or impractical to evaluate. Therefore, reference levels, which utilise metrics that are more practical to evaluate, are also provided as an alternative means of demonstrating compliance with the mandatory basic restrictions. The reference levels specified in the National Guidelines are: time averaged and instantaneous electric (E) and magnetic (H) field strengths; limb currents (IL) and; contact currents (IC). For each basic restriction, Table 1 indicates the reference levels that shall be satisfied in order to deem compliance with the corresponding basic restriction. It should be noted that the reference levels have been conservatively formulated so that non-compliance with the reference levels does not necessarily imply non-compliance with the corresponding basic restriction(s). Refer to section 1.5 for detailed definitions of each basic restriction and reference level.


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Basic Restriction Corresponding Reference Levels

Instantaneous J (3 kHz-10 MHz) Instantaneous E and/or H (3 kHz – 10 MHz) and instantaneous IC (3 kHz - 10 MHz)

Time averaged WBA SAR (100 kHz - 10 GHz)

Time averaged E and/or H (100 kHz – 10 GHz)

Time averaged localized SAR in the limbs (100 kHz – 10 GHz)

Time averaged E and/or H (100 kHz– 10 GHz) and/or time averaged IL (10 MHz-110 MHz) and instantaneous IC (10 MHz - 110 MHz)

Time averaged localized SAR in head & torso (100 kHz - 10 GHz)

Time averaged E and/or H (100 kHz - 10 GHz)

Instantaneous SA in the head (300 MHz - 10 GHz)

Instantaneous E and/or H (300 MHz - 10 GHz)

Time averaged Sinc (10 GHz–300 GHz) Time averaged E and/or H (10 GHz - 300 GHz)

Table 1 Relationship between basic restrictions and reference levels. Note that ‘and/or’ implies that either both quantities or individual quantities can be evaluated to show compliance with the basic restrictions, depending on the circumstances of exposure.

2.2.2 Public and Occupational Limits Public and Occupational limiting values are provided for the basic restrictions and reference levels which shall be applied according to the circumstances of exposure. The occupational limits apply to the exposure of designated RF trained workers (see definition) who have been formally identified as such under a workplace RF safety program and are generally exposed under known conditions. By contrast, the public limits apply to individuals of all ages and of varying health status, and may include particularly susceptible groups or individuals. In many cases, members of the public are unaware of their exposure to EMF. It is these considerations that underlie the adoption of more stringent exposure restrictions for the public than for the occupationally exposed population. The public limits also apply to all mobile or portable radio devices that are certified not to exceed the public limit. (e.g. mobile phones, wireless modems, Wi-Max and Wi-Fi peripherals, cordless handsets).


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2.3 Basic Restrictions

2.3.1 General The basic restrictions are intended to provide protection against established adverse health effects as indicated in Table 2. Since each basic restriction applies to a different potential mechanism for harm, they shall each be individually complied with, even where they may overlap in applicable frequency range.

Adverse health effect Relevant basic restriction Unit

Electrostimulation and electric shock or burns

J: internal current density averaged over a specified area

mA/m²

Whole body heating WBA SAR: Specific Absorption Rate averaged over the entire body

W/kg

Localized tissue heating Localized SAR: Specific Absorption Rate averaged over a localized mass of tissue

W/kg

Microwave hearing effect SA: Specific Absorption of RF energy per pulse in a defined mass of tissue

mJ/kg

Surface heating Sinc: incident power flux density averaged over a specified area

W/m²

Table 2 Relationship between established adverse RF health effects and basic restrictions.

2.3.2 Induced Current Density The basic restrictions on current density (J) induced in the head and torso of the body from RF exposure are provided in Table 3. They are primarily intended to provide protection against electrostimulatory effects. The following rules shall apply to the evaluation of J:

a) J shall be spatially averaged over any 1 cm² that is oriented perpendicular to the direction of current flow.

b) J shall be time averaged over any continuous 0.2 sec period of RF exposure. c) For RF pulses of duration tp, the equivalent frequency to apply for the J reference

level is ƒ = 1 / (2tp).

Exposure category Frequency range Current density in the head and torso (mA/m² rms)

Public 3 kHz – 10 MHz 2 × ƒkHz

Occupational 3 kHz – 10 MHz 10 × ƒkHz

Table 3 Basic restrictions for current density in the head and torso. The value ƒƒƒƒkHz is the RF exposure frequency in kHz.


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2.3.3 Whole Body Average Specific Absorption Rate The basic restrictions on whole body average specific absorption rate (WBA SAR) are provided in Table 4. They are primarily intended to provide protection against systemic whole body heating effects. The following rules shall apply to the evaluation of WBA SAR:

a) WBA SAR shall be evaluated by dividing the total RF power (W) absorbed in the body by the total body mass (kg).

b) WBA SAR shall be time averaged over any continuous 6 minute period of RF exposure.

Exposure category Frequency range WBA SAR (W/kg)

Public 100 kHz – 10 GHz 0.08

Occupational 100 kHz – 10 GHz 0.4

Table 4 WBA SAR basic restrictions.

2.3.4 Localized Specific Absorption Rate The basic restrictions on localized specific absorption rate (localized SAR) are provided in Table 5. They are primarily intended to provide protection against localized tissue heating effects. The basic restrictions for the torso and head (except the pinnas) are lower than those for the limbs in order to provide greater protection for the eyes, brain and other vital organs. The following rules shall apply to the evaluation of localized SAR:

a) Localized SAR shall be evaluated by spatially averaging the SAR over any 10g of body tissue in the shape of a cube.

b) Localized SAR shall be time averaged over any continuous 6 minute period of RF exposure.

Exposure category Frequency range Localized SAR in the head & torso

(W/kg)

Localized SAR in the limbs and the pinnae

(W/kg)

Public 100 kHz – 10 GHz 2 4

Occupational 100 kHz – 10 GHz 10 20

Table 5 Basic restrictions for localized SAR in the head/torso and limbs/pinnae.


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2.3.5 Specific Absorption The basic restrictions on specific absorption (SA) in the head for pulsed RF exposures are provided in Table 6. They are primarily intended to provide protection against the microwave hearing effect. The following rules shall apply to the evaluation of SA:

a) SA shall be evaluated as the total energy delivered by the RF pulse to any 10g of head tissue, in the shape of a cube, divided by the mass of the cube.

b) The SA basic restriction shall only apply to RF pulses with duration of 50 µs or less.

Exposure category Frequency range SA (mJ/kg)

Public 300 MHz – 10 GHz 2

Occupational 300 MHz – 10 GHz 10

Table 6 Basic restrictions for SA in the head.

2.3.6 Incident Power Flux Density The basic restrictions on power flux density that is incident at the surface of the body (Sinc) are provided in Table 7. They are primarily intended to provide protection against excessive surface heating of the body. The following rules shall apply to the evaluation of Sinc:

a) Sinc shall be spatially averaged over any 20 cm² square area that intersects with the surface of the body.

b) Spatial maximum Sinc averaged over any 1 cm² square area in the 20 cm² averaging area defined in 2.3.6(a) shall not exceed 20× the basic restriction values provided in Table 7.

c) Sinc shall be time averaged over any continuous 68/ƒ1.05 minute period of RF exposure, where ƒ is the frequency in GHz.

Exposure category Frequency range Sinc (W/m²)

Public 10 – 300 GHz 10

Occupational 10 – 300 GHz 50

Table 7 Basic restrictions for Sinc at the surface of the body.


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2.4 Reference Levels

2.4.1 Time averaged Electric and Magnetic Field Strength The public and occupational reference levels for the time averaged electric (E) and magnetic (H) field strengths are specified in Table 8 and Table 9. The additional column for Seq (W/m²) is merely a unit conversion of the E and H reference levels in terms of equivalent plane wave power flux density (see definition). It may be noted that for frequencies above 10 MHz, the E and H reference levels convert to the same values of Seq. The following rules shall apply to the evaluation of time averaged E and H exposure:

a) E and H exposures shall be evaluated as the ambient RF levels, i.e. unperturbed by the presence of any person.

b) E and H exposures shall be evaluated no closer than 10 cm from the surface of a fixed RF source or from the surface of a mobile or portable device that is not intended for use close to the body.

c) E², H² and Seq shall be time averaged using the averaging times specified in Table 8 and Table 9.

d) E², H² and Seq shall be spatially averaged or assessed as a spatial peak value as specified in Clause 2.4.3.

Frequency range E (V/m rms)

H (A/m rms)

Seq (W/m²)

Averaging time for E², H² or Seq

(min)

100 – 150 kHz 86.8 4.86 — 6

0.15 – 1 MHz 86.8 0.729/ƒ — 6

1 – 10 MHz 86.8 /ƒ 0.5 0.729 /ƒ — 6

10 – 400 MHz 27.4 0.0729 2 6

0.4 – 2 GHz 1.375 × ƒ 0.5 0.00364 × ƒ 0.5

ƒ /200 6

2 – 10 GHz 61.4 0.163 10 6

10 – 300 GHz 61.4 0.163 10 9.6 × 104 /ƒ 1.05

Table 8 Public reference levels for time averaged E and H. The variable ƒƒƒƒ denotes the frequency in MHz.


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H (A/m rms)

Seq (W/m²)

Averaging time for E², H² or Seq

(min)

0.1 – 1 MHz 614 1.63 /ƒ — 6

1 – 10 MHz 614/ƒ 1.63 /ƒ — 6

10 – 400 MHz 61.4 0.163 10 6

0.4 – 2 GHz 3.07×ƒ 0.5 0.00814×ƒ 0.5

ƒ /40 6

2 – 10 GHz 137 0.364 50 6

10 – 300 GHz 137 0.364 50 9.6 × 104 /ƒ 1.05

Table 9 Occupational reference levels for time averaged E and H. The variable ƒƒƒƒ denotes the frequency in MHz.

2.4.2 Instantaneous Electric and Magnetic Field Strength The public and occupational reference levels for instantaneous electric (E) and magnetic (H) field strengths are provided in Table 10 and Table 11. The following rules shall apply to the evaluation of instantaneous E and H exposure:

a) E and H exposures shall be evaluated as the ambient RF levels, i.e. unperturbed by the presence of any person.

b) E and H exposures shall be evaluated no closer than 10 cm from the surface of a fixed RF source or from the surface of a mobile or portable device that is not intended for use close to the body.

c) E² and H² shall be time averaged over any continuous 0.2 sec period. d) E² and H² shall be spatially averaged or assessed as a spatial peak value as specified in

Clause 2.4.3.


H (A/m rms)

3 – 100 kHz 123 6.87

100 – 150 kHz 86.8 × 10α 4.86 × 10α

0.15 – 1 MHz 86.8 × 10α (0.729 /ƒ) × 10α

1 – 10 MHz (86.8 /ƒ 0.5) × 10α (0.729 /ƒ) × 10α

10 – 400 MHz 877 2.33

0.4 – 2 GHz 44 × ƒ 0.5 0.116 × ƒ 0.5

2 – 300 GHz 1965 5.22

Table 10 Public reference levels for instantaneous E and H. The variable ƒƒƒƒ denotes the frequency in MHz. The variable αααα is calculated as 0.665 log10(10××××ƒƒƒƒ) + 0.176


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H (A/m rms)

3 – 65 kHz 868 35.3

65 – 100 kHz 868 2.31 /ƒ

0.1 – 1 MHz 614 × 10α (1.63 /ƒ) × 10α

1 – 10 MHz (614/ƒ) × 10α (1.63 /ƒ) × 10α

10 – 400 MHz 1964 5.22

0.4 – 2 GHz 98.2 × ƒ 0.5 0.260 × ƒ 0.5

2 – 300 GHz 4384 11.6

Table 11 Occupational reference levels for instantaneous E and H. The variable ƒƒƒƒ denotes the frequency in MHz. The variable αααα is calculated as 0.665 log10(10××××ƒƒƒƒ) + 0.176

2.4.3 Spatial averaging rules for E and H reference levels The E and H reference levels that are provided in Sections 2.4.1 and 2.4.2 are intended to be spatially averaged values over the entire body of the exposed individual, but with the important condition that the basic restrictions on localized exposure (section 2.3) are not to be exceeded. Spatial averaging should not be applied for the evaluation of mobile or portable radio devices, or in close proximity to primary and re-radiating sources. However, spatial averaging evaluations for the fixed radio sources, addressed in IEEE Std C95.3-2002, shall be deemed suitable if used within the constraints and conditions recommended for spatial averaging in that standard. Information about any spatial averaging scheme used during evaluations should be provided in the assessment report. Although different spatial averaging schemes may be employed, the following schemes are recommended.

a) For frequencies below 10 GHz: For cases where whole body RF exposures of standing persons occurs, measurements should be spatially averaged over a vertical height of 0.2 to 1.8 m at the location of the exposure. For cases that require spatial averaging around a peak spatial field, the spatially averaged measurement is determined by scanning between 0.2 to 1.8 m at the location of exposure to find the peak spatial field in the region. The peak spatial measurement and two additional measurements at vertical points around it, one wavelength above and below, are averaged to determine the spatially averaged value of the field.

b) For frequencies above 10 GHz:

The spatially averaged measurement is determined by scanning between 0.2 to 1.8 m at the location of exposure to find the peak spatial field in the region. The measurements over a square of 20cm2 centred at this location are averaged to determine the spatially averaged value of the field.


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2.4.4 Limb currents The public and occupational reference levels for limb currents (IL) are provided in Table 12.

Exposure category Frequency range I L (mA)

Public 10 – 110 MHz 45

Occupational 10 – 110 MHz 100

Table 12 Reference levels for limb currents. The following rules shall apply to the evaluation of IL:

a) IL shall be time averaged over any continuous 6 minute period. b) IL in the lower limb (leg) shall be evaluated as the total current flow through the ankle. c) IL in the upper limb (arm) shall be evaluated as the total current flow through the wrist

while making grasping contact with an RF energised conductor. d) Measured evaluations of IL should be performed using a current probe (see definition)

clamped on the wrist or ankle.

2.4.5 Contact currents The public and occupational reference levels for contact currents (IC) are provided in Table 13.

Exposure category Frequency range I C (mA)

Public 3 – 100 kHz 0.2 × ƒ

0.1 – 110 MHz 20

Occupational 3 – 100 kHz 0.4 × ƒ

0.1 – 110 MHz 40

Table 13 Reference levels for contact currents. The variable ƒƒƒƒ denotes the frequency in kHz. The following rules shall apply to the evaluation of IC:

a) IC shall be time averaged over any continuous 0.2 sec period. b) IC shall be evaluated as the total current flow through the wrist when making fingertip

contact with an RF energised conductor. c) Measured evaluations of IC should be performed using a current probe (see definition)

clamped on the wrist.


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2.5 Simultaneous Exposure to Multiple Frequency Fields

2.5.1 General In situations of simultaneous RF exposure to multiple frequencies, the possibility that these exposures will be additive in their effects shall be considered. In particular, total exposure evaluations of the basic restrictions and reference levels for simultaneous exposure to multiple frequencies shall be performed separately for electrostimulatory and thermal effects on the body as specified in sections 2.5.2 and 2.5.3. For fixed RF sources the compliance site manager is responsible for ensuring simultaneous RF exposures are taken into account (refer sections 4.2 and 4.3).

2.5.2 Basic restrictions For electrostimulatory effects, the current densities arising over any square 10 cm² cross section from simultaneous multiple frequency RF exposures shall be summed according to:

1MHz 10

kHz 3

≤∑=i L, i

i

J

J

where

Ji is the current density at frequency i; JL, i is the current density basic restriction at frequency i given in Table 3;

For whole body thermal effects, WBA SAR shall be summed according to:

∑=

GHz 10

kHz 001

SARWBA SARWBA

i L

i

where

WBA SARi is the WBA SAR caused by RF exposure at frequency i; WBA SARL is the relevant WBA SAR basic restriction specified in Table 4;

For localized thermal effects, the localized SAR in any 10g averaging cube or Sinc averaged over the same surface area of the body from simultaneous multiple frequency RF exposures shall be summed according to:

1SAR Localized

SAR LocalizedGHz 10

kHz 001

≤∑=i L

i

1GHz 300

GHz 01

≤∑>j L

j

S

S

where

Localized SARi is the localized SAR caused by RF exposure at frequency i; Localized SARL is the localized SAR basic restriction given in Table 5; Sj is the incident power flux density at frequency j; SL is the incident power flux density basic restriction given in Table 7.


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2.5.3 Reference levels For electrostimulatory effects from simultaneous multiple frequency RF exposures, the following two total exposure evaluation requirements shall be applied:

1MHz 10

kHz 3

≤∑=i L, i

i

E

E

1MHz 10

kHz 3

≤∑=i L, i

i

H

H

where

Ei is the instantaneous electric field strength at frequency i; EL, i is the instantaneous electric field strength reference level at frequency i given in

Table 10 for public assessments or Table 11 for occupational assessments; Hi is the instantaneous magnetic field strength at frequency i; HL, i is the instantaneous magnetic field strength reference level at frequency i given in

Table 10 for public assessments or Table 11 for occupational assessments; For shock and burn effects from simultaneous multiple frequency induced RF currents at a contact point with an RF energised surface, the following total exposure evaluation requirement shall be applied:

1MHz 110

kHz 3

≤∑=i C, i

i

I

I

where

I i is the contact current component at frequency i; IC, i is the reference level for contact current at frequency i given in Table 13.


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For thermal effects from simultaneous multiple frequency RF exposures, the following three total exposure evaluation requirements shall apply:

1

2GHz 300

kHz 100

≤

∑

=i L, i

i

E

E

1

2GHz 300

kHz 100

≤

∑

=i L, i

i

H

H

1

2MHz 110

MHz 10

≤

∑

=j L, j

j

I

I

where

Ei is the time averaged electric field strengthen at frequency i; EL, i is the time averaged electric field reference level at frequency i specified in Table 8

for public assessments and Table 9 for occupational assessments; Hi is the time averaged magnetic field strength at frequency i; HL, i is the time averaged magnetic field reference level at frequency i specified in

Table 8 for public assessments and Table 9 for occupational assessments; I j is the limb current component at frequency j; IL, j is the reference level for limb current at frequency j specified in Table 12;


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3 Compliance of mobile or portable radio devices

3.1 Parties responsible for compliance Table 14 lists the parties that shall be deemed liable to the CITC for ensuring and demonstrating compliance of mobile or portable radio devices. Assignment of responsibility varies according to the type of the device and whether its use is controlled by a private owner or a non-private (corporate) entity.

Cas

e Device type Control of the device

Responsible parties for ensuring compliance

1 Mobile phones, wireless modems, Wi-Max and Wi-Fi peripherals, and cordless handsets which have not been modified from the original manufacturer’s specifications.

Private The importer or local manufacturer of the device.

2 Non-private

The importer or local manufacturer of the device. The corporate entity which controls the use of the device.

3 Mobile or portable radio device: a) with an integral antenna, AND; b) which has not been modified from the original manufacturer’s specifications, AND; c) is not one of those devices identified in cases 1-2.

Private The importer or local manufacturer of the device.

4 Non-private

The importer or local manufacturer of the device. The corporate entity which controls the use of the device.

5 Other mobile or portable radio devices than those identified in cases 1-4.

Private The private owner of the device

6 Non-private The corporate entity which controls the use of the device.

Table 14 Parties responsible for ensuring and demonstrating compliance of mobile or portable radio devices. The device types for cases 1-4 are intended to encompass mobile or portable radio devices with stable and well-defined radio emission characteristics that would allow the manufacturer or importer to reliably estimate the maximum RF exposure for standard or reasonably foreseeable uses of the device. Device types that may fall under cases 3-4 include wireless microphones, walkie-talkies (or two-ways), camera backs and body mounted radio transceivers. The device types of cases 5-6 encompass devices that have radio emission characteristics that may be significantly altered by the owner or user. These cases typically apply to piecemeal assemblies of transmitters, cabling and antennas that may be arranged in variable ways at the discretion of the user and/or owner. Common examples are vehicle mounted communication systems and external broadcast links. Note that this category also includes those device


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specified in cases 1-4 that have been modified from the original manufacturer’s specifications – e.g. the application of after-market accessories from third party suppliers. With regard to control of the device, the ‘private’ category in Table 14 refers to the use of a mobile or portable radio device that is privately owned. The ‘non-private’ category encompasses all other circumstances where the device is operated under the management control of a commercial, volunteer or government corporate entity that falls within the scope of the National Guidelines.

3.2 Compliance obligations of responsible parties

3.2.1 Importers or local manufacturers Table 15 prescribes compliance obligations on importers or local manufacturers of mobile or portable radio devices (as identified in cases 1-4 in Table 14) that are not inherently compliant (see section 3.3.1).

Case Compliance obligation on the importer or local manufacturer of the device

1, 2 Configure the device by its design and/or user procedures so that it is compliant with the public limits of the National Guidelines.

3, 4 Configure the device by its design and/or user procedures so that it is compliant with either the public or occupational limits of the National Guidelines.

1-4 If compliance of the device is dependent on user procedures (e.g. transmission duty cycles for push to talk devices, or separation distances of the body from the device) then ensure that clear and accessible instructions for such procedures are provided with the device at the point of sale.

3, 4 If the device could produce RF exposures that exceed the public limits during its intended use, then ensure that a clear and accessible written caution advising of this potential exposure and relevant precautions is provided with the device at the point of sale. See Annex 1 for recommended advisory text.

1- 4 Submit a Declaration of Conformity to the CITC for the device (Refer to Schedule 1 for information required in the Declaration of Conformity). However, if the device has been SAR tested for compliance with the National Guidelines (ICNIRP Guidelines) and approved by a laboratory that has accreditation to ISO/IEC 17025 standard for the relevant measurement methodologies, or to the ISO/IEC 17020 standard for the relevant calculation methodologies, then the device is deemed to comply with the National Guidelines and a Declaration of Conformity is not required.

Table 15 Compliance requirements for importers or local manufacturers of mobile or portable radio devices identified in cases 1-4 of Table 14.

3.2.2 Corporate entities Table 16 prescribes the compliance obligations on corporate entities (commercial, volunteer or government) with respect to a mobile or portable radio device that is under their management control (as identified in cases 2, 4 and 6 in Table 14) and is not inherently compliant.


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Case Compliance obligation on the corporate entity

2, 4 Ensure that any information provided by the manufacturers or importers of the device, which is pertinent to achieving compliance with the public limits, is made available to all users of the device.

6 Conduct or arrange an RF assessment of the device and implement appropriate user procedures if necessary for compliance.

4, 6 Ensure that only RF Trained workers are permitted to use the device if it generates an RF exposure that exceeds the public limits during its intended use, and that they receive any information pertinent to achieving compliance of the device with the occupational limits. Refer to Annex 5 for an example of how written RF safety information may be provided with the device.

6 Submit a Declaration of Conformity to the CITC for the device. Refer to Schedule 1 for information required in the Declaration of Conformity.

4, 6

Devise and implement an RF safety program for use of all mobile or portable radio devices under the management control of the corporate entity. Refer to Annex 2 for advice on devising an RF safety program.

Table 16 Compliance requirements for corporate entities identified in cases 2, 4, 6 of Table 14.

3.2.3 Private owners Table 17 prescribes the compliance obligations on private owners of a mobile or portable radio device as identified in case 5 in Table 14.

Case Compliance obligation on the private owner

5 Conduct or arrange an RF assessment of the device and devise and implement an RF safety program for its safe use.

5 Ensure that only RF Trained workers are permitted to use devices that are assessed to be compliant with the occupational limits, but not public limits.

Table 17 Compliance requirements for private owners identified in case 5 of Table 14.


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3.3 Compliance assessments

3.3.1 Inherently compliant device Any mobile or portable radio device operating with a net transmitter RF power of less than or equal to 20 mW shall be deemed to be inherently compliant with all of the requirements of the National Guidelines. Higher power devices may be inherently compliant if assessed according to the IEC 62479 standard, using the latest published version at the time of assessment.

3.3.2 Assessment standards SAR assessments of mobile or portable radio devices shall be conducted according to the test methodologies of the IEC 62209-1 and/or IEC 62209-2 standards as applicable, using the latest published version at the time of assessment. In the case of any conflict between the National Guidelines and the IEC 62209 standards, the requirements of the IEC standards shall prevail. Reference level assessments of mobile or portable radio devices shall be conducted according to the test methodologies of the IEC 62311 standard, using the latest published version at the time of assessment. In the case of any conflict between the National Guidelines and the IEC 62311 standard, the requirements of the IEC standard shall prevail. Figure 1 gives a flow chart of information and actions needed to assess compliance of mobile and portable radio devices.


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Determine Source characteristics (frequency/waveform, power, normal usage etc)

Low power/inherently

compliant device? (refer 3.4.1)

Intended to be used with radiating part of device in

close proximity to the human head against the

ear, frequency range 300 MHz to 3 GHz?

Compliant

Assess fields/currents at user position according to IEC62209-1

Assess reference levels at user position according to IEC62311

No

No

Yes

Yes

Intended to be used with radiating part of handheld or body mounted device in close proximity to the body, frequency range 30 MHz to 60 GHz?

Assess fields/currents at user position according to IEC62209-2

No

Yes

Figure 1 Compliance Assessment flowchart for mobile or portable radio devices


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3.3.3 Device conditions during assessment In general, compliance assessments of mobile or portable radio devices shall be based on conditions leading to the highest RF exposure that is possible for the intended use of the device, excluding fault conditions. Push to talk devices (such as walkie talkies or CB radios) shall be presumed to transmit for only 50% of the time over any six-minute period (i.e. a 50% duty cycle).

3.3.4 Reassessment of compliance Compliance of a mobile or portable radio device shall be reassessed if its configuration (device design or operational procedures) is changed in a way that could plausibly lead to the invalidation of the compliance assessment. Possible situations for reassessment are:

a) an increase in maximum transmitter RF power; b) an increase in the duty cycle of the transmitter; c) a reduction in transmission losses to the antenna; d) alteration of the antenna type; e) application of equipment add-ons to the device.


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4 Compliance requirements for fixed RF sources

4.1 Nomination of Compliance Sites A compliance site shall be nominated to the CITC for every fixed RF source (within the scope of the National Guidelines) that generates a public exclusion zone around it. A compliance site may encompass multiple fixed RF sources if these are attached to a common support structure such as a pole, tower, or building. The physical extent of the compliance site shall at least include the public exclusion zones associated with all fixed RF sources within the site. Barriers and/or signs shall be implemented to restrict access to the exclusion zones of the fixed RF sources within the compliance site. A compliance site shall not comprise multiple disconnected areas. If a public or occupational exclusion zone has been identified at a compliance site, appropriate signage, as shown in Annex 3, shall be installed at the site. RF safety signs shall be in Arabic and English.

A Notice sign shall be posted at all access control points to the compliance site indicating that the area beyond that point is under RF management and to alert persons to the potential for exposures exceeding the public limit. If a public exclusion zone exists at a publicly accessible area (i.e. rooftop), a Caution sign shall be posted at the compliance boundary to alert personnel to the possibility of exposures exceeding the public limit. If an occupational exclusion zone exists at an accessible area (i.e. rooftop, support structure), a Warning sign shall be posted at the compliance boundary or access point to alert personnel to the possibility of exposures exceeding the occupational limit.

4.2 Parties responsible for compliance

4.2.1 Radio licensees Radio licensees shall be liable to the CITC for ensuring and demonstrating compliance of any fixed RF source that is associated with the production or transmission of their licensed radio transmissions. Where there are multiple RF sources at a compliance site that are associated with multiple radio licensees, then all radio licensees shall assume shared liability (equally apportioned) to the CITC for compliance at the site. Requirements for multiple RF sources at compliance sites shall comply with the CITC Interconnection Guidelines.

4.2.2 Property owners Properties owners shall comply with any requests specified in section 4.4 from the CITC, radio licensees or their representatives for verifying or maintaining compliance of any fixed RF sources on their property.


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4.3 Obligations of radio licensees

4.3.1 General Section 4.3 specifies obligations on radio licensees for ensuring and demonstrating compliance of any fixed RF source that is associated with the production or transmission of their licensed radio transmissions.

4.3.2 Nomination of compliance sites A compliance site shall be nominated to the CITC for each fixed radio source as specified in section 4.1.

4.3.3 Assessments of exclusion zones The public exclusion zone shall be assessed for each fixed RF source. The occupational exclusion zone shall also be assessed if closer access to the fixed RF source for RF Trained workers is planned in the safe work procedures for the site.

4.3.4 Multi-source exposures The assessment of each fixed RF source shall include a consideration of total aggregate exposures (as per section 2.5) from any other nearby fixed RF source that generates more than 10% of the public reference levels (in terms of E², H², Seq, (IC)² and (IL)²) at any point within the public compliance boundary of the primary fixed RF source.

4.3.5 RF safety program An RF safety program (as specified in Annex 2) shall be developed and implemented for the safe management of the fixed RF sources within a compliance site.

4.3.6 RF compliance documentation An RF control document (RFCD) shall be prepared for the compliance site and submitted to the CITC. A Site Compliance Certificate shall be prepared for the compliance site and submitted to the CITC and the property owner. The required content of the RF compliance documentation is specified in Schedule 2.


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4.3.7 Compliance site manager A compliance site manager shall be nominated to the CITC for each compliance site. The name and contact details (telephone and email) of the compliance site manager shall be provided in the RFCD for the compliance site. The compliance site manager (or his nominee) shall represent the RF license holders in the following compliance site requirements:

a) nominate the compliance site to the CITC; b) arrange the production of an RFCD and Site Compliance Certificate for the

compliance site. c) submit the RFCD to the CITC; d) submit the Site Compliance Certificate to the CITC and the property owner; e) supervise the implementation of the RF safety program for the compliance site,

including any specific procedures in the RFCD; f) provide any information requested by the CITC relating to compliance at the

compliance site; g) arrange safe access to the compliance site for CITC inspectors (or their

representatives) for verification of compliance when requested by the CITC; h) when requested, provide sufficient RF exposure data to the compliance site managers

of nearby sites to meet their obligations for total exposure assessments (as per section 4.3.4);

i) notify other compliance site managers of nearby sites about the installation or modification of any new fixed RF sources within the compliance site;

j) notify the property owner before any compliance related visit to the property. The same compliance site manager may be nominated for multiple compliance sites. The compliance site manager may also be nominated from a third party, though liability to the CITC for compliance shall still nonetheless lie with the radio licensee(s).

4.4 Obligations of property owners

4.4.1 Cooperation with the CITC On request from the CITC, the property owner shall provide the name and contact details of either the owner, operator, or radio licensee associated with any fixed RF source (within the scope of the National Guidelines) on their property. The property owner shall also allow access to any fixed RF source or compliance site on their property for CITC inspectors or their representatives who require access for the purpose of verifying compliance.

4.4.2 Cooperation with a compliance site manager The property owner shall comply with any of the following requests from a compliance site manager on a compliance site that has been registered with the CITC for their property:

a) allow reasonable access to the compliance site for the compliance site manager or his representatives for the sole purposes of establishing or verifying compliance;


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b) allow the placement on the property of the RFCD and appropriate RF safety signs for the compliance site;

c) allow the establishment of appropriate access restrictions which are erected at the cost of the radio licensees represented by the compliance site manager (or his nominee);

d) notify visitors to their property, who may access the compliance sites, of the need to refer to the RFCD for ensuring their safety;

4.5 Compliance assessments

4.5.1 Assessment standards and guidelines The compliance assessment of a fixed RF source shall be conducted according to the test methods described in Annex 6 of these National guidelines, or the IEEE Std C95.3, Recommended Practice for Measurements and Computations of Radio frequency Electromagnetic Fields With Respect to Human exposure to Such Fields, 100 kHz – 300 GHz, using the latest published version at the time of assessment. In case of any conflict between assessments conducted using the IEEE C95.3 standard and the National Guidelines, the requirements of the National Guidelines shall prevail.

4.5.2 Source conditions during assessment In general, compliance assessments of fixed RF sources shall be based on conditions leading to the highest RF exposure that is possible for the intended operational states of the source, excluding fault conditions.

4.5.3 Reassessment of compliance Compliance of a fixed RF source shall be reassessed if its configuration (design or operational procedures) is changed in a way that could plausibly lead to the invalidation of the compliance assessment. Some possible situations for reassessment are:

a) an increase in transmitter RF power; b) an increase in the duty cycle of the transmitter; c) a reduction in transmission losses between the transmitter and the antenna; d) alteration of the antenna type or field pattern; e) change in the antenna bearing, height or location;

4.6 Requirements for compliance A site shall be compliant with the National Guidelines if the following requirements have been met:

a) All exclusion zones (public and occupational) have been identified at the site. b) The necessary site control measures have been implemented, as far as reasonably and

practicably possible, to ensure that: i) No RF trained worker is exposed to electromagnetic fields at the site that is

higher than the occupational limits; ii) No non-RF trained worker is exposed to electromagnetic fields at the site that is

higher than the public limits. c) Signs as detailed in section 4.1, have been installed on site; d) The necessary site compliance documentation has been submitted to the CITC.


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5 Enforcement The National Guidelines are mandatory in accordance with Section 1.4.

5.1 Enforcement powers of the CITC The CITC, in designating appropriate compliance arrangements under the National Guidelines may:

a) require the assessment of RF emitters; b) conduct or arrange compliance verification of RF emitters; c) require the provision of information and/or documentation relevant to verifying

compliance; d) prescribe an time period determined by the CITC for the compliance site manager to

submit the Declaration of conformity, RFCD and/or other documentation relevant to verify compliance;

e) prescribe mitigating actions where RF emitters or an RF safety program are not in compliance with the National Guidelines;

f) ban the sale of any mobile or portable radio device that has not been demonstrated to be in compliance with the National Guidelines;

g) make publicly available any DoC, RFCD and/or Site Compliance Certificate submitted to the CITC;

h) establish penalties where there is non-compliance with the National Guidelines as per section 7;

i) issue amendments to the National Guidelines; j) issue technical clarifications and interpretations for the National Guidelines; k) include any other measure necessary to ensure compliance with the National

Guidelines.

5.2 Verification of assessments

5.2.1 Mobile or portable radio devices The CITC will refer to the Declaration of Conformity (DoC) submitted for a mobile or portable radio device when verifying its assessment. In the first instance, the CITC will check that the DoC contains the valid information required in Schedule 1. The CITC shall accept, without further review, a DoC that is based on assessments conducted by a laboratory that has been accredited by its recognized accrediting agency to the ISO/IEC 17025 standard for the relevant measurement methodologies, or to the ISO/IEC 17020 standard for the relevant calculation methodologies. In other cases, the CITC may arrange further testing for verification of compliance using the same assessment standard indicated in the DoC.


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5.2.2 Fixed RF sources When checking compliance of a fixed RF source, the CITC will refer to the RF Control Document (RFCD) for the compliance site which contains the source. In the first instance, the CITC will check that the RFCD contains valid information required in Schedule 2. For fixed RF sources that have been assessed according to the IEEE C95.3 standard, the CITC may arrange further testing for verification of compliance using the same assessment methodology indicated in the IEEE C95.3 standard. The CITC shall determine non-compliance of a fixed RF source if the lower bound (see definition) of any verification test result exceeds the relevant reference level or basic restriction for the nominated compliance boundaries and RF safety procedures. For fixed RF sources that have been assessed to the Technical Guidelines described in Annex 6 of these National Guidelines, the CITC may verify compliance by checking that the assessment using this guideline is valid.

5.2.3 CITC Inspectors CITC Inspectors who are empowered to enter premises to conduct compliance verification of RF emitters shall:

a) have identification clearly identifying them as officials of the CITC. This identification shall be shown upon request;

b) be technically qualified and have suitable equipment that allows them to conduct compliance verification;

c) be given every reasonable assistance to enable him to carry out his duties or functions under the Act;

d) at any reasonable time and on reasonable grounds, enter premises to conduct any compliance procedures, including examination of any RF emitting device testing records or data and any other compliance information he may request, and opening packages that may contain RF emitting devices and taking them away for further inspection if necessary;

e) not detain the radiation emitting device after the expiration of 90 days from the day it was taken away unless, before that time, proceedings have been instituted in respect of a contravention of the National Guidelines, in which case the device may be detained until the proceedings are finally concluded;

f) maintain records and results of all compliance inspections and verifications;


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6 Distribution of compliance documentation The CITC establish and manage a centralized internet-based repository which contains information addressed to the public on DoC and RFCD compliance results. Information posted on the site should not be commercially “sensitive”.

7 Violations Violations to the National Guidelines are subject to relevant terms in article 37 of the Telecommunications Act.

8 Entry into force The National Guidelines shall enter into force on the date specified by CITC decision approving it.


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Schedule 1 – Declaration of Conformity This Schedule prescribes the contents and delivery requirements for a Declaration of Conformity (DoC) for a mobile or portable radio device. The DoC shall include the following:

a) The name and contact details of the corporate entity. b) The name, title and contact details of a person delegated within the corporate entity to

liaise with the CITC in relation to the DoC. c) A brief description of the device including:

i) its generic type (e.g. mobile phone, wireless microphone, two-way radio, etc) ii) its model number iii) manufacturer of the device

d) A statement declaring that the device complies with the public, occupational, or both (depending on device procedures) limits of the National Guidelines.

e) Citation of the standard used to assess compliance with the public and/or occupational limits of the National Guidelines (IEC62209 or IEC62311).

f) The name and address of the laboratory or test house that performed the compliance assessment.

g) The date when the compliance assessment was completed. h) A brief description of the test device operating configurations during assessment

including: i) operating modes and frequency range(s); ii) net transmitter RF power for each operating mode and frequency range; iii) operating net transmitter RF power tolerances; iv) antenna type and operating positions; v) applicable body–worn configurations; vi) battery options that could affect the RF exposure assessments; vii) applicable source-based time-averaging duty cycle and the duty cycle used in the

tests; i) Any user procedures that are required to ensure compliance of the device such as:

i) device power settings ii) separation distance of the device from the body

j) A graphical depiction of the public or occupational exclusion zones around the device (if these extend more than 10 cm from the device). Such depictions shall be labelled with any relevant device configuration information for identifying the depicted exclusion zone. (See S2.4)

The DoC shall be signed and dated by an authorised representative of the corporate entity.


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Schedule 2 – Compliance Documentation

S2.1 RF Control Document requirements The general aim of the RF Control Document (RFCD) is to identify and describe all known RF exclusion zones within a compliance site and specify the local control strategies for minimising the risk of exposure above the limits of the National Guidelines. In particular, an RFCD shall contain at least the following compliance site information:

a) The name and contact details of the site compliance manager b) Name of the radio licensees responsible for the compliance site c) Site compliance status (i.e. “needs assessment”, “compliant”, or ”non-compliant”) d) Date of issue and version number (v1, v2, v3, …) of the RFCD e) Document revision index that identifies any significant changes from the previous

version f) Table of contents g) Compliance site identification details, including:

i) site name (e.g. King Fahad International Stadium) ii) site identification code (see section S2.3) iii) site address iv) longitude and latitude (GPS co-ordinates)

h) Details of all fixed RF sources associated with the radio licensees within the compliance site, including: i) antenna type, make and model ii) antenna location on the site iii) azimuth direction (main beam with respect to true north) iv) electrical and mechanical tilt (degrees) v) operating frequency bands vi) net transmitter RF power per antenna port vii) transmitter RF power viii) installation support structure (e.g. mast, building, wall, other) ix) photographs of the compliance site (preferably North, East, South and West

panoramic views, as well as close-up shots from which all antennas can be identified).

i) Description of any other fixed RF sources that are not associated with the radio licensees on the compliance site to enable total RF assessment as per section 4.3.4, including: i) antenna type ii) Antenna location on the site

j) Details of the methodology used for assessments at the compliance site, including: i) the name of the assessment standard or guideline used to assess compliance of

the fixed RF sources at the site ii) the reference levels and/or basic restrictions that have been applied for

determining compliance at the site iii) the make, model and calibration date of any measurement equipment used for RF

exposure evaluations at the site iv) identification of any calculation technique or commercial software program used

for RF exposure calculations v) an estimate of the upper bound (see definition) for all evaluations (measured or

calculated) used to determine compliance k) RF safe work procedures for the site l) A description of RF exclusion zone access restrictions and signage for the site


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m) Drawings that indicate any applicable exclusion zones for the fixed RF sources (See S2.4)

The RFCD should be viewed by anyone with an interest in RF safety at the site including property owners, site managers, their associates, contractors and staff. In particular, occupationally exposed workers on the site shall familiarise themselves with the entire contents of the RFCD before commencing work on the site, and shall adhere to the RF safe work practices prescribed in this document.

S2.2 Site Compliance Certificate requirements The Radio Licensee shall issue a Site Compliance Certificate to CITC stating that the site is in compliance. The Site Compliance Certificate shall contain at least the following compliance site information:

a) Compliance site identification details, including: i) site name (e.g. King Fahad International Stadium) ii) site identification code (see section S2.3) iii) site address iv) Longitude and Latitude (GPS co-ordinates)

b) The name and address of the accredited laboratory or test house from CITC that performed the compliance assessment.

c) The date when the compliance assessment was completed. The Site Compliance Certificate shall be signed and dated by an authorised representative of the Radio Licensee.

S2.3 Site identification code Each compliance site shall post a sign showing its identification code and the name and logo of the RF Licensee; thus each site will have a unique identification code (unique ID).

S2.4 Graphical depiction of exclusion zones A public exclusion zone shall be graphically depicted as a yellow solid, cross-hatched or semi transparent area that is overlayed on a drawing or photo of the fixed RF source. An occupational exclusion zone shall be graphically depicted as a red solid, cross-hatched or semi transparent area that is overlayed on a drawing or photo of the fixed RF source.


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Annex 1 – Example advisory text for RF Trained worker mobile or portable radio devices An example of advisory text that should be provided with mobile or portable radio devices that exceed the public (but not occupational) limits is provided below:

CAUTION: Radiofrequency electromagnetic field exposures from this device may exceed levels that are recommended for Public in the National Guidelines for Human Exposure to Radiofrequency Electromagnetic Fields, which have been issued by the Communications and Information Technology Commission (CITC) of the Kingdom of Saudi Arabia. Accordingly, this device should only be used by RF trained workers as defined in the CITC National Guidelines.


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Annex 2 – Development of an RF safety program

A2.1 General An RF safety program (RFSP) is a policy framework that shall be implemented and monitored by any corporate entity (commercial, volunteer or public) that is deemed by the National Guidelines to be responsible for the compliance of any mobile or portable radio device or fixed RF source. The main aspects of an RF safety program are:

a) The establishment of corporate roles and responsibilities for ensuring compliance (section 3.1);

b) Compliance assessments of mobile or portable radio devices and fixed RF sources; c) The implementation of safety control measures to mitigate the risk of exposure above

the limits of the National Guidelines; d) The designation of RF Trained workers; e) RF safety awareness and training; f) Response to over-exposure incidents; g) Documentation.

The following sections of Annex 2 provide guidance on implementing an RF safety program. Further, more detailed, guidance may also be obtained from the IEEE C95.7 standard; Recommended Practice for Radio Frequency Safety Programs, 3kHz to 300GHz.

A2.2 Roles and responsibilities The corporate roles and responsibilities for ensuring RF safety compliance may vary according to the size and the structure of the corporate entity. The following parts of section A2.2 provide an example of how they might be defined for a large organisation. Senior management Senior management should ensure that staff with designated roles and responsibilities for RF safety have adequate authority, opportunity and resources to properly discharge their duties. RF Safety Committee (RFSC) An RF Safety Committee may be formed from senior representatives from the major stakeholder groups within the organisation who are affected by the RF safety issue, e.g. operations, health and safety, legal, corporate affairs and human resources. Its role would be to review and approve any policy changes in the management of RF safety in the organisation. RF Safety Officer (RFSO) The RF Safety Officer would have a national supervisory and operational role for managing RF safety within the organisation, and would report directly to the RF Safety Committee. This position would entail the following duties:

a) Monitor all KSA regulations and standards relating to RF safety; b) Disseminate information on RF safety policy within the organisation;


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c) Provide authoritative advice to staff on the interpretation of all relevant policies and procedures related to RF safety, seeking counsel from the RF Safety Committee where necessary;

d) Respond to general public enquiries about the RF safety of the organisation’s radio equipment;

e) Provide technical advice to Legal, Corporate Affairs, Strategy, Operational, Occupational Health and Safety (OH&S) and other major stakeholders on RF safety issues as required;

f) Provide technical support on RF safety issues to the site compliance managers as required;

g) Review and authorise RF surveys, RF control documents and RF safety sheets submitted by the site compliance managers or their delegates;

h) Authorise designation of qualifying personnel as RF Trained workers and maintain a list of approved RF Trained workers;

i) Manage medical fitness assessments of RF Trained workers for exposures above the public limits;

j) Coordinate RF safety awareness or measurement training for appropriate staff and maintain training records;

k) Conduct or arrange regular site audits (once every three years) of compliance with the RF safety policies and procedures stipulated by the RF safety program;

l) Conduct an annual review of RF exposure survey policies and procedures to ensure that they adequately reflect best practices and regulatory requirements, and submit an amended draft to the RF Safety Committee for comment and approval;

m) Manage the investigation of any breaches of the policies and procedures of the RF safety program, including accidental RF over-exposure incidents, and develop appropriate policy amendments if required;

n) Develop or approve appropriate RF exposure assessment tools; o) Arrange the regular calibration of RF exposure survey or monitoring equipment,

including all RF field measurement kits, RF personal monitors and RF current probes; p) Ensure proper control and central archiving of all documentation associated with RF

safety in the organisation. Site compliance managers As specified in section 4.3.7. General staff It is the responsibility of all field staff, technicians, engineers, managers and any other organisation employees concerned with RF safety to observe the policies and procedures of the RF safety program, and in relevant site safety documentation, with regard to their own safety or for other persons under their supervision.

A2.3 Safety Controls This section covers general safety control measures for ensuring compliance for all types of services, as applicable. Ideally it is best to remove or minimize the risk by reducing the exclusion zones to zero. However, this is seldom feasible due to radio coverage requirements when operating an RF service. Other more practical control measures exist for managing the risk from RF exposure. Control of RF Exposure by use of engineering controls should be implemented whenever feasible. Administrative controls, since they imply and/or require user knowledge, interpretation or action, should only be used if engineering controls are not feasible, or to supplement engineering controls.


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A2.3.1 Engineering Controls Engineering controls are measures to reduce the possibility of personal RF over exposure by the design or configuration of equipment or by the physical location of the radiating structure. Engineering controls can be implemented to remove or reduce exclusion zones and may comprise any of the following measures: a) Reducing transmitter RF power – leads to a reduction in size of exclusion zones; b) Relocating antennas away from accessible areas; c) Re-engineering antenna configurations – leads to newly configured exclusion zones; d) Installation of physical person proof barriers – eg locked doors, cages or fences that

positively restrict access to areas that include exclusion zones. Examples of access controls on a rooftop site include locked doors to the rooftop. Examples of access controls for a structure include anti-climb barriers, locked ladder cages or the removal of the bottom segment of ladders on towers.

e) Fitting antenna radomes – to limit access to antenna feeds/horns where RF energy is concentrated. If a public exclusion zone exists in close proximity to the antenna, then a sufficient engineering control would be to install a radome around the antenna that is large enough to completely enclose the public exclusion zone.

f) Application of RF shielding, particularly for transmitter equipment; g) Avoiding the use of open line feeders; h) Use of fail-safe interlocks; i) Built in leakage detectors.

Engineering control measures are not mandatory but generally reduce the requirement for administrative control measures.

A2.3.2 Administrative Controls Administrative controls include introducing safe work systems and procedures, installation of signage, installation of warning barriers (eg chains, rails, paint), RF awareness training and/or assigning RF safety personnel, and use of personnel protective equipment. The effectiveness of administrative controls is dependant on the awareness and participation of personnel.

a) Signage Areas where the potential exists for RF exposures to exceed public exposure limits should be clearly marked with appropriate signs, barricades or ground markings. If a public or occupational exclusion zone has been identified at a compliance site, appropriate signage (see Annex 3 for examples) shall be installed at the site.

RF safety signs should employ multiple languages where appropriate. As a minimum, Arabic and English languages shall be employed.

Notice signs are posted at all access control points to the compliance site indicating that the area beyond that point is under RF management and to alert persons to the potential for exposures exceeding the public limit.

If a public exclusion zone exists at a publicly accessible area (i.e. rooftop), Caution signs are to be posted at the compliance boundary to alert personnel to the possibility of exposures exceeding the public limit.


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If an occupational exclusion zone exists at an accessible area (i.e. rooftop, support structure), Warning signs are to be posted at the compliance boundary or access point to alert personnel to the possibility of exposures exceeding the occupational limit.

b) Safe Work Practices Limiting or restricting access to areas where the potential exists to be exposed in excess of the appropriate exposure limit can be accomplished with appropriate work practices. For example, locking and having doors with alarms, permanent warning signs and barriers, and similar access controls may be sufficient to limit access.

At some compliance sites (such as rooftop or wall mounted sites) it might not be feasible to ensure exclusive access using (physical) barriers. In these cases, if it can be reasonably expected that non-RF Trained workers would have easy access to public exclusion zone(s) then the site should be re-engineered. If it is unlikely, but possible, that members of the general public would gain access to the exclusion zone(s) at the site then the following measures would be sufficient:

i) Clear demarcation of the exclusion zones using painted lines on the roof surface

around the fixed RF sources. A durable paint and a single yellow line should be used at the edge of the public exclusion zone. Appropriate signs (see signage requirements below) should be installed at access control point.

ii) Alternatively, hand rails, (with appropriate signs), should be installed at the edge of the public exclusion zone(s).

c) Site Access Procedures The purpose of site access procedures is to ensure that only trained RF Trained workers are allowed access to an RF site and to document all site visits into public and occupational exclusion zones. Site compliance managers should ensure that these procedures are introduced and adhered to. The minimum requirements for site access procedures are as follows: i) For access outside any public exclusion zone, no specific RF access procedures

are required; ii) For access inside a public but outside an occupational exclusion zone:

1) site visits, including names of all persons should be documented, and 2) people should be instructed that anyone with electronic medical implants or

metallic implants (who have not been certified as RF trained workers) are not allowed to enter any exclusion zone;

iii) For access inside an occupational exclusion zone: 1) site visits, including names of all persons should be documented, 2) people should be instructed that anyone with electronic medical implants or

metallic implants (who have not been certified as RF trained workers) are not allowed to enter any exclusion zone, and

3) switch off or reduce the power of transmitters to appropriate levels to ensure that the RF fields are below the occupational limit.


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A2.4 Training RF awareness training should be provided to all persons who have to access areas where RF exposure can exceed the public limits. The same training should be provided to the RF Safety Committee members and RF Safety Officer.

A2.4.1 RF safety awareness training RF safety awareness training is required for all persons designated as RF trained workers in order to provide reasonable awareness of all necessary procedures for ensuring compliance and how to minimise RF exposure. The extent of the training may depend on the anticipated circumstances of exposure. It may range from a simple briefing for limited exposures to in-depth training for potentially dangerous RF sources or devices.

For RF trained workers who are exposed to a wide range of RF sources or devices under limited supervision, more comprehensive training is indicated. A recommended list of learning outcomes for such training is provided in Annex 4.

A2.4.2 Registration of RF trained workers The names of all persons who have been designated as RF trained workers by a corporate entity should be formally recorded in an RF trained worker registry. The RF registry should also record the RF awareness training and medical screening required for designation of each RF trained worker. The RF trained worker registry should be made available to the CITC on request.

A2.4.3 Medical screening All workers should have a standard pre-employment medical examination to ensure their fitness to work. This medical examination will also serve as a baseline for future medical conditions that may be attributed to their employment. Persons with electronic medical implants (such as pacemakers or infusion pumps) could be at higher risk from RF exposure due to possible radio interference with such devices. Persons with metallic implants (such as orthopaedic rods and plates) could also be at higher risk due to the possible increase of localized heating around the implants. A RF safety risk assessment on any electronic medical or metallic implants in the body should be obtained for each person before designation as an RF trained worker. For electronic medical implants, it is advisable to consult the physician who inserted the implant or the manufacturer to determine the risk of radio interference on the function of the implant. For metallic implants, refer to the relevant chapter of the International EMF Dosimetry Handbook (http://www.emfdosimetry.org/) for guidance on assessing the risk of RF field concentrations around the implant.


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A2.5 Personal RF monitors Personal RF monitors should be used in cases of uncertainty of the levels of RF exposure in the area(s) where work is to be performed, or where work for extended periods will be done in close proximity to antennas (especially at complex sites), or for visits to sites by non RF trained workers. All RF trained workers should be trained in the use of a personal RF monitor as part of the RF exposure awareness training certification.

A2.6 RF protective clothing RF protective clothing may be used as a last resort where access is required to areas above the occupational limits (e.g. for transit through high exposure areas on a TV tower). Only RF trained workers who have been trained in their proper use should use such suits.

A2.7 RF over exposure incidents RF over exposure can cause injuries related to frequency of the RF fields. Such injuries will be mostly due to heating at depth into tissues at high RF frequencies or to electric currents induced in tissues at low RF frequencies. Treatment of injuries should be based on the medical symptoms observed. For more information on treatment of persons overexposed to RF fields, refer to Medical Aspects of Radiofrequency Radiation Overexposure (COMAR, 2002). In the event of inadvertent exposure above the limits of the National Guidelines, the following post incident plan should be implemented:

a) If a minor RF injury has been sustained from the incident, apply first aid treatment as

required. For more serious injuries arrange timely and appropriate medical care based on the symptoms. Notify the CITC of the incident within 24 hours if there are any injuries that require attention from doctor.

b) All over-exposure incidents should be notified to the relevant compliance site manager as soon as practicable.

c) An RF overexposure incident form should be completed by the over-exposed person and submitted to the site compliance manager.

d) The RF Safety Officer and the compliance site manager should jointly investigate the cause of the incident and make timely recommendations as to how a recurrence of the incident could be avoided.

e) The RF Safety Officer should determine whether the incident justifies any amendment to the corporate RF safety program policies, draft any necessary changes and submit to the RF Safety Committee (or other relevant reviewer) for approval.

f) The RF Safety Officer shall keep a log of all notified incidents and report this data to the RF Safety Committee.


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A2.8 Identification of RF exclusion zones Appropriate numerical modelling tools and/or measurement equipment are essential in assessing and identifying exclusions zones for Fixed RF services. There are several methods by which this objective can be reached; each one having its own merits depending on the characteristics of the site. A2.8.1 Generic Safe Distance Rules

Generic safe distance rules can be used to determine the exclusion zones at non-complex base station sites, i.e. sites with one transmitter / antenna or sites having isolated transmitters/antennas (spaced such that no overlapping of RF exclusion zones exists). Sites with high power transmitters are excluded from generic modelling. Advantages of this method are that the process is fast and accurate. The applicable generic safe distance rules and more detailed explanations on when these rules can be applied are presented in Annex 6 of the National Guidelines.

A2.8.2 Numerical modelling (desktop assessment) Numerical modelling methods are recommended for calculating the RF exclusion zones of sites consisting of two or more antennas that are closely located to each other (i.e. antennas have overlapping RF exclusion), or for calculating RF exclusion zones in the near field of antennas (e.g. in the immediate vicinity of relatively low power HF communication antennas). The process is more involved than Generic Safe Distance Rules but has significant time savings compared to site surveys involving measurements, and is sufficiently accurate for this purpose. Numerical modelling for installations must be performed using scientifically based guidelines until such time as appropriate international standards for base station assessments has been published. Various commercial software packages are available to perform such simulations.

A2.8.3 Physical site measurements Measurement surveys are recommended for exclusion zone assessments at sites with unknown variables, unstable control measures, very high power transmitters and/or sites being shared by various operators and technologies. For example, sites that cannot reliably be assessed using any of the techniques proposed above. Instrumentation for RF measurements and RF measurement procedures have been specified in IEEE Standard C95.3.


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Annex 3 – Recommended RF safety Signage

A3.1 Type and nature of RF safety signs RF safety signs indicate the nature and degree of RF exposure associated with a given fixed RF source or compliance site. The nature of the RF exposure is indicated by a symbol, and a sign bearing words to that effect indicates the degree of the exposure. The size of the sign shall be such that it is clearly distinguishable under the appropriate conditions. Illumination or reflective materials should be used in areas where there is insufficient visibility of the sign. An example showing placement of recommended RF safety signage is shown below.


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A3.2 RF exposure awareness signs

A3.2.1 NOTICE Sign The purpose of the NOTICE sign is to make people aware that an RF compliance zone exists beyond that specific point. The sign colours and wording should correspond to that in the figure below (not to scale). Placement of the NOTICE sign should correspond with the guidelines provided in section 4.1.

THE AREA BEYOND THIS

POINT IS AN RF COMPLIANCE

MANAGEMENT ZONE


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A3.2.2 CAUTION Sign The purpose of the CAUTION sign is to warn people that beyond that specific point or within the demarcated area, RF exposure levels may exceed the public limits. The sign colours and wording should correspond to that in the figure below (not to scale). Placement of the CAUTION sign should correspond with the guidelines provided in section 4.1.

BEYOND THIS POINT RF

LEVELS EXCEED THE LIMITS

FOR THE PUBLIC

NO MEMBER OF THE PUBLIC SHOULD

ENTER THIS AREA WITHOUT

APPROPRIATE APPROVAL


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A3.2.3 WARNING Sign The purpose of the WARNING sign is to warn people that, beyond that specific point or within the demarcated area, RF exposure levels will exceed the occupational limits. The sign colours and wording should correspond to that in the figures below (not to scale). Placement of the WARNING sign should correspond with the guidelines provided in section 4.1.

“Self adhesive type” Warning sign

BEYOND THIS POINT RF

LEVELS EXCEED THE

OCCUPATIONAL LIMITS

RF TRAINED WORKERS SHOULD NOT

ENTER THIS AREA UNLESS PRECAUTIONS

ARE TAKEN TO REDUCE RF LEVELS

BELOW OCCUPATIONAL LIMITS

RF TRAINED WORKERS SHOULD NOT

ENTER THIS AREA UNLESS PRECAUTIONS

ARE TAKEN TO REDUCE RF LEVELS

BELOW OCCUPATIONAL LIMITS

BEYOND THIS POINT RF LEVELS

EXCEED THE OCCUPATIONAL LIMITS


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Annex 4 – Recommended key learning outcomes for comprehensive RF safety awareness training

Learning Unit 1 – RF Fields & Standards At the completion of this learning unit, participants should be able to:

a) State that RF consists of electric and magnetic fields travelling as waves; b) Explain the difference between RF and ionizing radiation; c) List the three established mechanisms for RF biological effects (i.e., heating,

electrostimulation, and microwave hearing effect); d) Explain, in general terms, how RF absorption in the body changes with frequency; e) List the potential health effects of high exposure to RF; f) Identify the National Guidelines as the applicable standard for ensuring RF safety; g) Identify the different types of basic restriction and reference level limits in the

National Guidelines and state that these vary with frequency; h) Define an RF trained worker.

Learning Unit 2 – RF Safety Policies At the completion of this learning unit, participants should be able to:

a) State where the corporate policies of the RF safety program may be obtained; b) State the medical screening requirements for RF trained workers; c) Outline potential over-exposure procedures; d) Identify the roles and responsibilities of the entities for managing and ensuring RF

safety; e) Outline the procedures for supervising non-RF trained workers on compliance sites; f) Explain how safety signs and barriers are used to control access to exclusion zones. g) Demonstrate the correct use of corporate compliance site safety procedures; h) Outline the procedure to reduce transmitter RF power and/or switch off transmitters;

Learning Unit 3 – Identifying RF Exclusion zones At the completion of this learning unit, participants should be able to:

a) State the corporate policy on compliance site entry procedures; b) State how a site may be identified as a compliance site; c) State how RF safety controls can be determined for a site; d) Identify the four general characteristics of an RF source (transmitter RF power,

performance, effective aperture and frequency) that affect its RF exposure potential; e) State the RF exposure characteristics of typical RF sources encountered in the entities

environment; f) State the important components of RF site safety documentation.

Learning Unit 4 –Verification and monitoring At the completion of this learning unit, participants should be able to:

a) State reasons for using a personal RF monitor; b) Identify the characteristics of the personal RF monitors used by the entity; c) Demonstrate the correct use of the personal RF monitor; d) State the precautions to be observed when using the personal RF monitor; e) State the necessary service and calibration checks for the personal RF monitor.


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Annex 5 – Written RF safety information provided with a mobile or portable radio device The general purpose of the RF Safety Sheet (RFSS) is to provide a one page description of the important RF exposure features of a mobile or portable radio device. It provides this information in a clear and simple format that can be readily interpreted by a lay reader and provides sufficient information for its safe use. The RFSS provides information on:

a) Identification details of the radio device (e.g. make and model); b) Who assessed it and when; c) The device's transmission frequencies and transmitter RF power levels; d) Simple diagrams showing public and occupational exclusion zones around the device; e) Any important RF safety procedures required for the device.

A laminated copy of the RFSS that is either attached to the device or stored in its equipment case would provide a handy reference for any users of the device.


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Annex 6 – Technical Guidelines and Safe Vertical and Horizontal Distances for the Installation of Base Station Antennas

A6.1 Objective To establish generic guidelines for the installation of base station antennas (macro- and micro-cells) to ensure that the vertical and horizontal clearance distances are such that the installations are inherently compliant with the National Guidelines.

A6.2 Scope Although the National Guidelines are applicable to a wide range of fixed radio communication infrastructures and radio communication devices, the generic guidelines in this annex are applicable only to the fixed radio communications infrastructure of mobile telephony services.

A6.3 Definitions

Inherently compliant BTS: A BTS site that transmits a small enough amount of RF energy to be considered compliant with the National Guidelines even if no signage is displayed or access is restricted. Normally compliant BTS: A BTS site that is designed in such a way that the exclusion zones are normally restricted or controlled. Therefore the site will be compliant with the National Guidelines if notice signs are prominently displayed where a person would normally enter the physically restricted area (refer to Annex 2 of the National Guidelines for further information regarding access restriction and signage requirements). Non-compliant BTS: A BTS site that is not compliant with the National Guidelines and for which it is impossible to rectify the situation by using signage or restriction of access.

A6.4 Introduction The most effective way to ensure compliance to the National Guidelines when constructing a mobile telephone network is to ensure that each new BTS site is designed and erected in such a way that the site is either inherently compliant or normally compliant. This is not always possible due to practical and technical considerations, but a network operator should aim for a normally compliant. In general it is not possible to define generic or easy to use installation rules for fixed RF infrastructures that would ensure compliance with the National Guidelines. This is due to the vast number of different configurations that are possible. Nonetheless, it is possible to define such easy to follow rules when considering mobile telephone network installations. This annex provides technical guidance on the safe vertical and horizontal distance clearance that should be maintained when planning mobile BTS sites. The safe distances will be applicable to the majority of sites in a typical mobile telephone network. Macro sites with panel and omni-directional antennas as well as indoor and outdoor micro sites are considered. The applicability and limitations of the technical guidelines are clearly defined in the different sections. If a BTS installation does not fall into the category for which this annex is applicable, a more detailed analysis would be required when considering compliance to the National Guidelines.


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A6.5 Macro BTS Sites Macro BTS sites are usually installed on free standing masts, roof tops or against building walls. Another less common type of macro BTS site is a distributed antenna system (DAS) as described in A6.5.3. Macro sites transmit more power than micro sites but access to macro sites are normally more restrictive (with the exception of distributed antenna systems). Both omni-directional antennas and directional panel antennas can be deployed at a macro site. In this section safe horizontal and vertical distances will be presented that can be used as guidelines when planning and constructing macro BTS sites. A6.5.1 Directional Panel Antennas

The shape of the exclusion zone around a typical single-panel tri-band (eg. antenna operating with three technologies: GSM900, GSM1800 and UMTS) BTS antenna with typical electrical down tilt is shown in Figure A6.1. The Red (dark shade) lobe represents the occupational exclusion zone while the yellow (light shade) lobe represents the public exclusion zone. A description of each distance parameter and numerical value for each parameter is given in Table A6.1. These distances were determined for a BTS with the characteristics described in Table A6.2. The characteristics were selected to represent most BTS installations.

Top view

Side view

Figure A6.1: Graphical presentation of the exclusion zone


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Description Parameter Distance [m]

Length of compliance distance in front of antenna. Measured from front of antenna.

LL 14.5

Length of compliance distance at the back of the antenna. Measured from the back panel of the antenna.

LB 0.5

Shortest distance from the side of the antenna to the exclusion zone boundary. Distance measured from the side of the antenna.

LS 0.5

Width of the exclusion zone boundary. Maximum width of the exclusion zone lobe is used.

LW 9.5

Distance from the antenna centre to where the full width of the exclusion zone boundary begins.

D 2.5

Length to exclusion zone boundary above the antenna. Measured from the top of the antenna upwards.

HA 0.5

Length to exclusion zone boundary below the antenna. Measured from the base/bottom of the antenna downwards.

HB 0.5

Table A6.1: Public exclusion zone distances (see Figure A6.1) for a tri-band panel antenna at a BTS site with characteristics as in Table A6.2

Notes on Table A6.1:

• The RF exposure behind (LB) and to the side (LS), top and bottom (HA, HB) of the antenna is minimal compared to the National Guidelines, but the public exclusion zone is extended to at least the touch distance from the antenna.

• LB does not apply to wall mounted antennas. In this case the public will not be able to touch the antenna from behind. The attenuation of RF through the wall will effectively make LB equal to the wall thickness.


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Tri-band antenna with a mechanical tilt of between 0˚ and 6˚ downward

GSM900

Polarization Dual polarizations, 40 W radiated on each

Electrical Tilt 7˚

Antenna Gain 17 dBi

GSM1800


Electrical Tilt 5˚

Antenna Gain 16.5 dBi

UMTS


Electrical Tilt 3˚

Antenna Gain 17 dBi

Table A6.2: Transmit and tilt characteristics used for conservative exclusion zone calculations for a directional antenna


• In practice more than one radio carrier can be combined and transmitted on any one of the polarizations of the antenna. If this is the case a 3 dB combiner loss is assumed, which effectively makes the maximum transmitted power on each polarization 40 W (GSM900 and GSM1800) and 20 W (UMTS).

• With the exception of combiner loss, which was assumed to be 3 dB, no other losses, including all cable loss and antenna loss, were taken into account while determining the parameters. Disregarding system losses will result in conservative distance parameters.

• The electrical tilt angles at each frequency, where the calculations were done, are typical values used in practice for these frequency bands.

The distance parameters of Figure A6.1 and Table A6.1 can be used as guidelines for macro sites with directional antennas, and can also be used as a conservative estimate for BTS sites with: • Single or dual-band transmissions. • Transmitter RF power less than those given in Table A6.2 for any frequency bands. • Electrical tilt angles less than those specified in Table A6.2 for any frequency bands.

The application at different types of macro sites will be discussed in the subsequent sections.


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A6.5.1.1 Free standing masts To ensure that a BTS installation on a mast (Figure A6.2) is normally compliant the following guidelines shall be adhered to:

• All structures in front of each panel antenna should be a distance LL away. Structures closer than LL in front of a panel antenna should be at least a height ht (with ht = 2 meters) lower than the bottom boundary of the public exclusion zone. The parameter ht is a conservative height assumed for a person that might have access to the top of the structure.

• Ensure that access to the mast is normally restricted by a gate / fence at the bottom with a Notice Sign (see Annex 3 for signage details).

Free standing mast site antenna

Side view Top view

Figure A6.2: Single panel antenna mounted on a mast

A

ht

ht

A

A


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A6.5.1.2 Rooftop installations Figure A6.3 shows a rooftop BTS site. To ensure normal compliance at a rooftop site the following guidelines shall be adhered to:

• All panel antennas shall be mounted such that the bottom boundary of the exclusion zone is higher than ht (with ht = 2 meters) on any rooftop walking area around the antenna.

• All neighbouring structures in front of each panel antenna on a rooftop should be a distance LL away. Structures closer than LL in front of a panel antenna should be at least a height ht (with ht = 2 meters) lower than the bottom boundary of the public exclusion zone.

Roof top site

Side view Top view

Figure A6.3: Single panel antenna used at a rooftop site

ht

A

A

A


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A6.5.1.3 Wall mounted installations Figure A6.4 shows a typical wall mounted antenna at a BTS site. For wall mounted installations to be normally compliant, the following guidelines shall be adhered to:

• All neighbouring structures directly in front of each wall mounted panel antenna should be a distance LL away. Structures closer than LL in front of a panel antenna should be at least a height ht (with ht = 2 meters) lower than the bottom boundary of the public exclusion zone.

• Wall mounted antennas shall be installed at least a distance LS away from any window.

Wall mounted BTS site

Side view Top view

Figure A6.4: Single panel antenna mounted on a wall

A

A

A

ht

ht

LS


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A6.5.1.4 Co-located panel antennas at macro sites

The exclusion zone of a panel antenna could change due to the presence of co-located antennas. The distance between the antennas and the orientation (direction of the main beam) are factors that need to be taken into account. A few co-located scenarios that will typically be found at BTS sites are presented in Table A6.3. If antennas were located closer to each other than the minimum distances presented in Table A6.3, for the corresponding scenarios, a more detailed analysis would be required. Commercial software is readily available to analyse these scenarios.

Antenna configuration Minimum distance

0 m

17 m

43 m

71 m

Table A6.3: Minimum distances for tri-band panel antenna (Table A6.2) independence.


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A6.5.2 Omni Directional Antenna

Omni-directional antennas are also commonly used at macro BTS sites and specifically on free standing masts. The exclusion zones around omni-directional antennas are typically much smaller than with panel antennas.

Figure A6.5: Single omni-directional antenna mounted on mast

The exclusion zone around an omni-directional antenna can be specified using one horizontal distance parameter. This is the radius of the circle around the antenna which defines the zone (see Figure A6.6). The RF exposure above and below an omni is minimal compared to the National Guidelines. As is the case with panel antennas, the public exclusion zone is extended to at least the touch distance of 0.5 m from the antenna top and bottom.

A description of each distance parameter as well as the numerical value for each parameter is presented in Table A6.4. These distances were determined for a BTS with a 40 W transmitter in the GSM900 band, an electrical and mechanical tilt of 0˚, and an antenna gain of 11 dBi. This will account for most BTS sites with omni-directional antennas in a mobile telephony network.

The distance parameters of Figure A6.6 and Table A6.4 can be used as guidelines for macro sites with omni-directional antennas, and also as a conservative estimate for BTS sites with less transmitter RF power than 40 W.


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Figure A6.6: Exclusion zone around an omni-directional antenna

Parameter Description Parameter Distance [m]

Exclusion zone distance around the antenna r nc 2.1

Exclusion zone distance below the antenna bnc 0.5

Exclusion zone distance above the antenna tnc 0.5

Table A6.4: Public exclusion zone distances (see Figure A6.6) for a GSM900 omni-directional antenna at a BTS site with 40 W transmitter RF

power and zero electrical and mechanical tilt.

A6.5.2.1 Co-located omni-directional antennas at macro sites

Similar to panel antennas, if multiple omni-directional antennas are situated in close proximity to each other, the exclusion zones around the antennas would change. The minimum distance between two omni-directional antennas to ensure exclusion zone independence (operating with GSM900 and 40 W transmitters) is presented in Table A6.5. If antennas are located closer to each other than the minimum distance presented in Table A6.5, for the corresponding scenario, a more detailed analysis would be required.


11 m

Table A6.5: Minimum distance for omni-directional antenna (GSM900, 40 W) independence

rnc

bnc

tnc


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A6.5.3 Distributed Antenna System (DAS) A Distributed Antenna System (DAS) BTS site uses the same transmitting equipment as normal macro sites, but distributes the transmitter RF power between a few indoor antennas. An example of such a site is shown in Figure A6.7. These types of cells can transmit in more than one frequency band but will transmit less power than normal macro cells since the power is distributed among several different antennas. Exclusion zones are smaller due to the low transmitter RF power.

The exclusion zone of a tri-band DAS antenna can be defined using three distance parameters. The parameters are shown graphically in Figure A6.8. The parameter descriptions and numerical values are presented in Table A6.6. The numerical values were calculated using 2 W transmitters (per frequency band), RF power in each of the three frequency bands (GSM900, GSM1800 and UMTS), and an antenna gain of 2 dBi. This will account for most DAS antennas.

The horizontal and vertical safe distance parameters presented in Table A6.6 and graphically depicted in Figure A6.8 can be used as guidelines for distributed antenna systems with omni-directional antennas.

For a distributed antenna system site to be normally compliant the following guidelines shall be adhered to:

• There should be no electrical devices (e.g. ceiling lights, see L in Figure A6.9) that could require maintenance in the exclusion zone of the antenna. The distance parameter ds in Figure A6.9 shall be greater than rnc given in Table A6.6.

Figure A6.7: Distributed antenna system on different floors in a building.


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• The antenna should be mounted such that the bottom of the exclusion zone is higher than ht in Figure A6.9 (with ht = 2 meters) from ground level.

Figure A6.8: Exclusion zone around an omni-directional tri-band DAS antenna; 2 W transmitter RF power for each band


Exclusion distance around the antenna. Radius from centre of antenna to exclusion zone cylinder side.

rnc 0.5

Exclusion distance below the antenna. Distance from bottom of antenna to exclusion zone cylinder bottom.

hb 0.5

Exclusion distance above the antenna. Distance from top of antenna to exclusion zone cylinder top.

ha 0.5

Table A6.6: Public exclusion zone distances (see Figure A6.8) for a tri-band omni-directional DAS antenna


• The RF exposure to the side (rnc), top and bottom (ha; hb) of the antenna is minimal compared to the National Guidelines, but the public exclusion zone is extended to at least the touch distance from the antenna.

• ha does not apply to ceiling mounted antennas since the public will not be able to touch the antenna from behind. The attenuation of RF through the ceiling will effectively make ha equal to the ceiling thickness.

• The distance parameters of Table A6.6 can also be used as a conservative estimate for DAS antennas with:

o Single or dual-band transmissions. o Transmitter RF power less than 2 W per antenna, for any frequency band.

rnc

hb

ha


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Figure A6.9: Exclusion zone for a ceiling mounted DAS antenna.

A6.6 Indoor and Outdoor Micro Cells Micro cell BTS sites are usually installed on outdoor or indoor walls or ceilings. They transmit less power than macros to cover a small area of less than 1 km2 and typically only operate at one frequency band. Omni-directional dipole or monopole antennas are typically used and the exclusion zones are small due to the low transmitting power.

A6.6.1 Indoor Micro Cells The exclusion zone of an indoor micro cell antenna can be defined using two distance parameters. The parameters for a single band indoor micro are shown graphically in Figure A6.10. The parameter descriptions are presented in Table A6.7. The numerical values presented in Table A6.7 are valid for a single frequency band micro cell at GSM900, GSM1800 or UMTS. These parameters were calculated using 2 W transmitters, and an antenna gain of 2 dBi. This will account, conservatively, for most micro cell BTS sites.

Figure A6.10: Exclusion zone around an omni-directional micro cell antenna.

dS

ht

L

hb

hb


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Exclusion distance around the antenna. Radius measured from centre of antenna to exclusion zone cylinder.

rc 0.5

Exclusion distance below the antenna. Distance measured from bottom of antenna to exclusion zone cylinder bottom.

Hb 0.5

Table A6.7: Public exclusion zone distances (see Figure A6.10) for a single band (GSM900, GSM1800 or UMTS) omni-directional micro cell antenna


• The RF exposure to the side (rc), and bottom (hb) of the antenna is minimal compared to the National Guidelines, but the public exclusion zone is extended to at least the touch distance from the antenna.

The distance parameters of Figure A6.10 and Table A6.7 can be used as guidelines for indoor micro cells with omni-directional antennas, and also as a conservative estimate for indoor micro cells with a transmitter RF power of less than 2 W.

For a micro cell site to be normally compliant the following guidelines shall be adhered to:

• There should be no electrical devices (e.g. ceiling lights, L in Figure A6.11) in the exclusion zone of the antenna that could require maintenance. The distance parameter d in Figure A6.11 shall be greater than rc in Table A6.7.

• The antenna should be mounted such that the bottom of the exclusion zone is higher than ht (with ht = 2 meters) from ground level.

Figure A6.11: Exclusion zone for a roof mounted indoor micro cell.

d L

ht


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A6.6.2 Outdoor Micro Cells The exclusion zone of an outdoor micro cell antenna can be defined using two distance parameters. The parameters for a single band outdoor micro are shown graphically in Figure A6.12. The parameter descriptions are presented in Table A6.8. The numerical values presented in Table A6.8 are valid for GSM900, GSM1800 or UMTS single frequency outdoor micro cells. These parameters were calculated using 2 W transmitter RF power and an antenna gain of 2 dBi. This will account, conservatively, for most outdoor micro cell BTS sites.

Figure A6.12: Exclusion zone around an omni-directional micro cell antenna.


Exclusion distance around the antenna. Radius measured from centre of antenna to exclusion zone cylinder.

rc 0.5

Exclusion distance below and above the antenna. Distance measured from bottom or top of antenna to exclusion zone cylinder.

ha 0.5

Total exclusion zone distance from below to above the antenna. Distance measured from bottom to top of exclusion zone cylinder.

hc (2 x ha) + (height of dipole)

Table A6.8: Public exclusion zone distances (see Figure A6.12) for a single band (GSM900, GSM1800 or UMTS) outdoor omni-directional micro cell antenna


• The RF exposure to the side (rc), top and bottom (ha) of the antenna is minimal compared to the National Guidelines, but the public exclusion zone is extended to at least the touch distance from the antenna.

The horizontal and vertical safe distance parameters presented in Table A6.8 and graphically depicted in Figure A6.12 can be used as guidelines for outdoor micro cells with omni-directional antennas, and can also be used as a conservative estimate for outdoor micro cells which transmit less power than 2 W.


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The application of two different types of outdoor micro cell sites will be discussed in the subsequent sections.

A6.6.2.1 Wall mounted

For a wall mounted outdoor micro cell site (see Figure 6.13) to be normally compliant the following guidelines shall be adhered to:

• There should be no windows in the exclusion zone of the antenna. Therefore d in Figure A6.13 shall be greater than rc in table A6.8.


Figure A6.13: Exclusion zone for an outdoor wall mounted micro cell.

A6.6.2.2 Pole mounted

For a pole-mounted outdoor micro cell site (see Figure 6.14) to be normally compliant the following guidelines shall be adhered to:


Figure A6.14: Exclusion zone for a pole mounted outdoor micro cell.

ht

d

ht


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A6.7 Digital Data Technology: Wi-Max

Wi-Max is a wireless digital communications system based on the IEEE 802.16 standard and can be used for wireless data transmission. Wi-Max was designed for Metropolitan Area Networks (MAN) and can provide broadband wireless access up to 50 km for fixed BTS stations.

Although there is no single global spectrum for Wi-Max, the Wi-Max Forum has published three licensed spectrum profiles: 2.3 GHz, 2.5 GHz and 3.5 GHz. The Kingdom of Saudi Arabia utilizes the 2.5 and 3.5 GHz frequency bands. Therefore exclusion zone distances are determined for a single Wi-Max panel antenna per sector for two different frequency bands: 2.5 GHz (20 W transmitter RF power) and 3.5 GHz (2.5 W transmitter RF power).

A.6.7.1 Wi-Max Panel Antennas The shape of the exclusion zone around a typical single Wi-Max panel antenna is shown in Figure A6.15. A description of each distance parameter and numerical value for each parameter is given in Table A6.9. These distances were determined for a Wi-Max antenna with the characteristics described in Table A6.10. The characteristics were selected to represent most Wi-Max antenna installations.

Top View

Side View

Figure A6.15: Exclusion zones around a Wi-Max panel antenna


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Descriptions of distance parameters Parameter

2.5 GHz Antenna Distance

[m]

3.5 GHz Antenna Distance

[m]

Compliance distance in front of antenna. Measured from the back panel of antenna. L L 2.8 0.6

Compliance distance at the back of the antenna. Measured from the back panel of the antenna. LB 0.5 0.5

Shortest distance from the centre of the antenna to the exclusion zone boundary at the side of the antenna.

LS 0.5 0.5

Maximum width of the exclusion zone boundary. LW 1.8 1.2

Distance from the antenna back panel to where the full width of the exclusion zone boundary begins. D 1.5 0.6

Length to exclusion zone boundary above the antenna. Measured from the top of the antenna upwards.

HA 0.5 0.5

Length to exclusion zone boundary below the antenna. Measured from the base/bottom of the antenna downwards.

HB 0.5 0.5

Table A6.9: Public exclusion zone distances and parameters for a Wi-Max panel antenna with characteristics as in Table A6.10

Notes on Table A6.9: • The RF exposure behind (LB) and to the side (LS), top and bottom (HA, HB) of the

antenna is minimal compared to the National Guidelines, but the public exclusion zone is extended to at least touch distance from the antenna.

• In practice, more than one radio carrier can be combined to transmit on the antenna. If this is the case, a 3 dB combiner loss is assumed, which effectively keeps the maximum transmitted power the same.

• With the exception of combiner loss, which was assumed to be 3 dB, no other losses, including all cable loss and antenna loss, were taken into account while determining the parameters. Disregarding the system losses will result in conservative distance parameters to the public exclusion zone.

• LB does not apply to wall mounted antennas. These antennas must be installed such that the public will not be able to touch the antenna from behind, i.e. far enough from windows or balconies. No exclusion zone will typically be present in rooms behind the antenna as the wall also attenuates the RF signals.

• If beam forming is used the exclusion zones will be enlarged, and a more detailed analysis would be required when considering compliance to the National Guidelines.


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Characteristic Wi-Max 2.5 GHz Wi-Max 3.5 GHz

Transmitter RF power 20 W 2.5 W

Antenna Gain 17 dBi 17 dBi

Horizontal beam width 65˚ 60˚

Vertical beam width 7˚ 9˚

Electrical Tilt 0˚ 0˚- 2˚

Table A6.10: Antenna characteristics used for Wi-Max panel antennas

A.6.7.2 Co-located Wi-Max Panel Antennas

The exclusion zone of a panel antenna could change due to the presence of co-located antennas. The distance between the antennas as well as their orientation (and direction of the main beam) are factors that need to be taken into account. A few co-located scenarios typically found at sites transmitting in the 2.5 GHz band are presented in Table A6.11. If antennas were located closer to each other than the minimum distances presented in Table A6.11, a more detailed analysis would be required.


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0 m

3.4 m

8.4 m

14 m

Table A6.11: Minimum distances for the 2.5 GHz Wi-Max panel antenna independence

Notes for Table A6.11 • The values in Table A6.11 were determined using methodology as for cellular

transmit antennas operating at almost the same frequency as the 2.5 GHz Wi-Max panel antennas.

• No minimum distances for independence of antennas are given for the 3.5 GHz antennas, since the frequency used is much higher than those for which the factors were determined. A full wave assessment with more antenna information will have to be performed to determine these distances.

A6.8 Assessment of other RF sources The ITU-T Recommendation K.61 Guidance on measurement and numerical prediction of electromagnetic fields for compliance with human exposure limits for telecommunication installations, contains information and formulae in order to provide guidance on assessments for other situations.

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