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FRAM-ini A qualitative fire risk assessment method 13-3-2014 FRAME Erik De Smet

FRAM-ini : A qualitative fire risk assessment method

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FRAM-ini: A qualitative fire risk assessment method FRAM-ini: A qualitative fire risk assessment method ............................................................................. 1

Introduction. ........................................................................................................................................ 2

Building FRAM-ini ................................................................................................................................ 2

Inspiration from machinery safety standards ................................................................................. 2

Input from FRAME ........................................................................................................................... 3

Limitations ....................................................................................................................................... 4

Property fire risk assessment .............................................................................................................. 4

Property Risk Assessment Flow Sheet ............................................................................................. 5

Fire duration category. .................................................................................................................... 6

Fire growth category . ..................................................................................................................... 7

Fire severity ..................................................................................................................................... 7

Building / compartment configuration ........................................................................................... 7

Available fire fighting means ........................................................................................................... 8

Fire fighting expediency .................................................................................................................. 9

Property fire risk class. .................................................................................................................... 9

Occupant fire risk assessment. .......................................................................................................... 10

Occupant fire risk assessment flow sheet ..................................................................................... 11

Ignition probability class. ............................................................................................................... 12

Fire growth category . ................................................................................................................... 13

Level of exposure........................................................................................................................... 13

Safe egress time margin. ............................................................................................................... 13

Occupant fire risk class .................................................................................................................. 14

Available protection level ................................................................................................................. 15

Property risk assessment worksheet ................................................................................................ 16

Occupant Risk Assessment worksheet .............................................................................................. 19


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Introduction. Users of the FRAME semi- quantitative fire risk assessment method expressed the wish for a less elaborate, qualitative fire risk assessment tool for people with a basic knowledge of fire safety. FRAM-ini is the tool developed for this purpose, but it can also be used as an introduction and step stone to the semi-quantitative FRAME approach.

Building FRAM-ini

Inspiration from machinery safety standards

FRAM-ini is inspired by the qualitative risk evaluation method described in the EN10501 and EN954-1 standards for safety of machinery. EN1050 presents a decision tree which uses the severity, the probability of occurrence and the exposure aspects of a potential hazard to define the risk class if no protection would be available. EN 1050 defines 5 risk classes and EN 954-1 indicates which protection category should be applied for a situation in each class to attain an acceptable level of residual risk. The risk classification is linked to 5 protection levels in the following decision diagram:

The 5 protection categories are: Protection category B(asic) means that the system is built according the state of art with good quality materials. This is the minimum allowed for risk class I. Protection category 1 means that the system is built according to the state of art with good quality materials, and the reliability of the safety system is guaranteed by testing, oversizing or duplication. This degree of protection is acceptable for risk classes I and II. Protection category 2 means that the installation meets the requirements of category 1 and the proper functioning of the safety elements is regularly monitored. This degree of protection is acceptable for risk classes II and III.

1 The EN 1050 standard has been replaced by the EN-ISO 14121-1:2007, but the principles remain valid.


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Protection category 3 means that the installation meets the requirements of category 2, a single fault of safety element does not entail the impairment of this function and the fault will be quickly detected. This degree of protection is acceptable for risk classes III and IV. Protection category 4 means that the installation meets the requirements of category 3, a single fault safety function is immediately reported and a multiple fault does not mean that the safety function is switched off. This degree of protection is required for the risk class V. FRAM-ini follows the same approach, and uses a decision tree to classify the fire risks in 5 classes.

Input from FRAME

In line with FRAME, there is a separate fire risk evaluation for the property and the occupants 2. As there are many influence factors to be considered in a fire risk risk assessment, weighed checklists were derived from the FRAME sub-factor calculations3. Such checklists allow a balanced evaluation of several parameters to produce sub-classes that are subsequently used in the decision tree process. In FRAME , the recommended approach is to tackle first the property risk assessment and to continue with the occupant risk, as this appears by experience to be the easiest way to define the appropriate overall level of protection. FRAM-ini uses also 5 protection categories, which are defined with the same components as in FRAME, and the link is given between the 5 risk classes and the corresponding adequate protection categories4. The five fire protection categories are: Basic: The users of the building are capable to detect a developing fire, leave the fire scene as necessary and call the fire brigade for help. The fire can be controlled easily. Category 1: There is a basic fire safety plan that tells the users how to react in case of fire and to call the fire brigade for help, and the building is equipped with manual fire alarm and fire fighting means. The fire brigade will intervene according to their standard procedures and be able to control the fire in a short time. Category 2: There is a detailed fire safety plan that tells the users how to react in case of fire, and the building is equipped with an automatic fire detection and alarm system and with manual fire fighting means. The fire brigade has established a specific fire intervention plan for the building. Fire control may be difficult under unfavourable circumstances. Category 3: There is a detailed fire safety plan that tells the users how to react in case of fire, and the building is equipped with an automatic sprinklers and and an occupant alarm system. The fire brigade has established a specific fire intervention plan for the building. Category 4: There is a detailed fire safety concept that includes a fire safety plan for the users, a specific fire intervention plan for the fire brigade and manual as well as automatic fire protection systems tailored to the characteristics of the building.

2 A risk assessment for business continuity as in FRAME is considered to be beyond the scope.

3 FRAME uses a large number of elements and sub-factors to produce a quantified risk assessment.

4 In FRAME, the adequacy of the protection level is defined by the benchmark value R≤1.


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Limitations

FRAM-ini can only be used to make a qualitative fire risk assessment. For smaller buildings, the risk assessment can be made for the whole building as one compartment, but for larger buildings, where it is possible to subdivide the building in compartments, it is better to make the fire risk assessment per compartment. When the resulting risk class would be too high, it might be useful to decide first on additional compartmentation and re-assess the fire risk for each of the new compartments. Classifying risks and protections in 5 classes and 5 categories is a mere decision tool. In practice, there is a wide variation of possible damage and a large spectrum of available protection systems. When in many cases the qualitative risk assessment is adequate to take a decision on the required protection level, the diversity of influence factors is so large that a more gradual approach of risks and protections is needed to develop a tailor-made (fire) safety concept . In such cases, the FRAM-ini decision tree will result in a “Not in scope” or “non applicable” mention. When a quantitative fire risk assessment is necessary, e.g. for the definition of an alternative or equivalent fire safety concept, FRAME or a more elaborate method shall be used in agreement with the stakeholders.

Property5 fire risk assessment The property fire risk class is defined by a eight steps decision tree. 5 risk classes (RCP I - RCP V) are defined with an increasing damage potential. The risk classes are defined for a fire situation where the fire has to be tackled by the fire brigade by the own means. Automatic fire detection and automatic extinguishing systems are not considered in this stage, but included in the protection category. RCP I : the damage to the compartment and its content is probably limited and repairable RCP II: the damage to the compartment and its content is probably significant but repairable RCP III: important damage in the compartment is likely, but damage to adjacent compartments unlikely RCP IV: total destruction of the compartment likely, damage outside the compartment is also possible RCP V: major fire loss possible Property fire risk class and protection categories are linked in the following scheme:

The risk class definition scheme is shown in the following flow sheet:

5 Property means the building and its content.


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Property Risk Assessment Flow Sheet

2. Fire growth category: defined by HRR DE1 Slow DE2 Moderate DE3 Average DE4 Fast DE5 Ultra fast

3. Fire severity category: SEV1 Very low SEV2 Low SEV3 Average SEV4 Increased SEV5 High SEV6 Very High

1. Fire duration category: defined by fire load density DU0 Short DU1 Medium DU2 Long

4. Compartment characteristics score COM Range : 1 to +20

5. fire fighting means score FFM. Range : 2 to 24

6. Fire fighting effectiveness EF 1 : very low EF 2: low EF 3 : medium EF 4 : high

7. Property fire risk class RCP I : limited damage and repairable RCP II : significant damage but repairable RCP III : important damage in the compartment RCP IV : total destruction of the compartment RCP V : major fire loss

8. Property protection category Basic: users of the building can detect a fire, leave the fire scene as necessary and call the fire brigade for help. Category 1: a basic fire safety plan exists and the building has manual fire alarm and fire fighting means. Fire brigade uses standard fire fighting procedures. Category 2: Detailed fire safety plan; the building has an automatic fire detection and alarm system and manual fire fighting means. The fire brigade has a specific fire intervention plan for the building. Category 3: Detailed fire safety plan and the building has an automatic sprinklers and and an occupant alarm system. The fire brigade has established a specific fire intervention plan for the building. Category 4: Detailed fire safety concept including a fire safety plan for the users, a specific fire intervention plan for the fire brigade and manual as well as automatic fire protection systems tailored to the characteristics of the building.


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Fire duration category.

The first step of the decision tree defines the fire duration, which is basically linked to the total fire load density in MJ/m² : The higher the fire load, the longer a fire will last. The fire load density can be subdivided into a variable (mobile) fire load density, defined by the occupancy and a permanent (immobile) fire load density, defined by the construction type. Typical mobile fire load densities6, based on statistics, are shown in the following table. For industrial occupancies, the classification found in the EN 12845 (sprinkler systems) is used as guideline .7

Type of occupancy total fire load density MJ/m²

11. Low fire hazard (LH or light hazard) occupancies 200

12. Offices 400

13. Dwellings and residential buildings 500

14. Educational : Schools, universities 200

15. Health care : Hospitals and similar 250

16. Hotels and similar 250

21. Ordinary fire hazard with low fire load : EN 12845 class OH1 600

22. Ordinary fire hazard with medium fire load EN 12845 class OH2 1500

23. Ordinary fire hazard with high fire load EN 12845 class OH3 2000

24. Ordinary fire hazard with very high fire load EN 12845 class OH4 2500

31. High hazard EN 12845 class HH1 2500



41. Rack storage above 6 m 6750

Typical immobile fire load densities are shown in the following table, based on building construction surveys:

Construction type total fire load density MJ/m²

1. Totally Incombustible ( e.g. concrete / steel only) 0

2. Incombustible construction, with max. 10% allowance for combustible construction elements as windows, roof covering, etc.

100

3. Wooden structure finished with incombustible materials. 300

4. Masonry construction with wooden floors and girders 300

5. Incombustible structure, combustible finishing. 1000

6. Totally combustible construction 1500

The total fire load density shall be defined by the sum of the values found in these tables and the fire duration is defined in the next table:

Total fire load density MJ/m² Fire duration category

TFLD ≤ 900 MJ/m² DU0 : Short

900 MJ/m² < TFLD ≤ 2300 MJ/m² DU1 : Medium

TFLD > 2300 MJ/m² DU2 : Long

Note: the limiting values in the fire duration table are defined in combination with the values in tables 1 and 2 to limit the choice to 3 coherent categories. It is not allowed to use here fire load density values found “elsewhere”.

6 These values are also used in FRAME for the the calculation of the fire load factor q.

7 This does not mean that sprinklers are necessarily required as fire protection


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Fire growth category .

The second step defines the fire growth category, which is linked to the content of the compartment, and the expected heat release rate (HRR) in kW/m². The following table gives 5 fire growth categories :8

Fire growth category

Typical HRR Typical content

DE1 Slow < 100 kW/m² Wet, incombustible , nearly incombustible or difficult to ignite (self extinguishing) materials, such as : machinery, household appliances, metal objects, incombustible (construction) materials, meat, green plants, …

DE2 Moderate 100 -250 kW/m² e.g. average content of residential buildings

DE3 Average 250 - 450 kW/m² Moderate to fast burning: for most buildings

DE4 Fast 450 - 700 kW/m² Buildings with predominantly materials like textile, wood, paper, dry food, solid plastics

DE5 Ultra fast 700 -1000 kW/m² Flammable and highly flammable materials such as expanded plastic packaging, wood dust, flammable liquids

Fire severity

In the third step, the fire duration and the fire growth categories are combined into 7 fire severity categories, ranging from a slow growing and short fire to an ultra-fast growing prolonged fire:

Fire duration / Fire growth DU0: Short DU1 : Medium DU2 : Long

DE1 Slow SEV1 : Very low SEV2 : Low SEV3 : Average

DE2 Moderate SEV2 : Low SEV3 : Average SEV4 : Increased

DE3 Average SEV3 : Average SEV4 : Increased SEV5 : High

DE4 Fast SEV4 : Increased SEV5 : High SEV6 : Very high

DE5 Ultra fast SEV5 : High SEV6 : Very high SEV7 : Extra high

Note: Situations resulting in a SEV7 “extra high” classification are usually unacceptable by any standard and are excluded further from the qualitative risk assessment .

Building / compartment configuration

The fourth step considers the impact of the building and compartment configuration on the fire fighting efforts. Certain aspects of the building configuration will render access to the fire scene by the fire brigade difficult or even hazardous and the available fire fighting may vary a lot from one place to an other. All these elements will influence the expediency of the fire fighting action. The following characteristics of the compartment configuration are considered : total floor area, access and frontage, floor level, floor to ceiling height, and structural fire resistance . For each of these characteristics, a score is given. A higher total score means more difficulties to work near the fire scene.

8 Such classification is also used for the t² fire growth curve. FRAME uses are more detailed approach for the

calculation of the fire growth factor i.


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Characteristic Evaluation criteria Score

Floor area: Atot m² Total floor area in the compartment, including mezzanines, platforms, and similar 9:

√

= 0,5 to >5

Access & Frontage Building only accessible at its narrow side double the value of g

+ 50 % of perimeter accessible for fire fighting 0

less than 50 % of perimeter accessible 2

Level Ground floor only 0

Compartment one level above the access level 4

Compartment located 2 or 3 levels above ground floor

6

Compartment located up to 8 levels above ground floor

10


12

Compartment located above 15th floor level 20

Below ground levels 10

Floor to ceiling Ceiling height < 3m 2

3m < ceiling height < 6m 1

Ceiling height > 6m 0

Structural fire resistance

R60 or more 0

R30 or more 4

Less than R30 9

Total score for the compartment characteristics COM = sum of scores

Available fire fighting means

The 5th step in the decision tree considers the available fire fighting means. The following points are evaluated: fire brigade class, arrival time of the first fire fighting team, public and private water supplies. A higher score total score means that a stronger fire fighting action can be organised.

Characteristic Evaluation criteria Score

Responding station of the fire brigade

1. Full time station 24 h/24 7 days/7 8

2. Professional crewed station ( day time crewed, night time retained )

6

3. Retained station (part time professionals) 4

4. Volunteer crewed station 2

First arrival time 1. First fire brigade arrival in less than 10 min 10

2. Arrival after 10 to 15 min 8


4. More than 30 minutes delay 0

Public water distribution and private water supplies for fire fighting

Capacity ≥ 120 m³, adequate distribution network, network static pressure ≥ 5 bar

6

Capacity < 120 m³ or pressure < 5 bar 2

Tanker or mobile pump required 0

Fire fighting means total score FFM = sum of scores

The adequacy of the water supply shall be confirmed by the fire brigade.

9 By this formula, the score is proportional to the diagonal of the compartment. A more elaborate formula is

used in FRAME


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Fire fighting effectiveness

The combination of the scores for the compartment characteristics and the fire fighting capacity give the level of fire fighting effectiveness :

Compartment / fire fighting means

COM ≤ 10 easy

10 < COM ≤ 14 limited

14 < COM ≤ 20 difficult

COM > 20 minimal

FFM ≥ 17 EF4 high EF3 medium EF2 low EF1 very low

17 > FFM ≥ 8 EF3 medium EF2 low EF1 very low

8 > FFM EF2 low EF1 very low

When the fire fighting expediency is low (levels EF1 and EF2 ), it will be necessary to include automatic systems in the fire protection concept to reduce the burden for the fire brigade.

Property fire risk class.

The 7th step combines the fire severity class and the fire fighting expediency level to define the property fire risk class. Where the fire severity is low and fire fighting conditions are favourable, there is only a minor potential for a large fire. On the other side of that spectrum, having a high probability of a major fire in a place where fire fighting is difficult is almost a guarantee for an uncontrollable fire development and hence a major fire loss. One cannot expect that the fire brigade can control a fire under any circumstances with their (limited) resources. There are situations where the responsible fire officers may conclude that a certain type of intervention is too risky and should be avoided to protect the firemen’s life. Under such conditions, the burden of fire control can not be borne by the fire brigade alone, and the building owners and users shall provide constructional and organisational measures as well as automatic fire protection systems as indicated to obtain an adequate level of protection. The combination of the fire severity class and the fire fighting expediency level gives the following property risk class distribution:

fire fighting expediency / fire severity

EF1 Very low

EF2 low

EF3 medium

EF4 high

SEV1 very low RCP III RCP II RCP I RCP I

SEV2 low RCP IV RCP III RCP II RCP I

SEV3 average RCP V RCP IV RCP III RCP II

SEV4 increased NAC RCP V RCP IV RCP III

SEV5 high NAC NAC RCP V RCP IV

SEV6 very high NAC NAC NAC RCP V

NAC : Such situations are not acceptable, preventive measures are needed to reduce the fire severity.


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Occupant fire risk assessment. The occupant fire risk class is defined by a five steps decision tree. 5 occupant risk classes (RCO I - RCO V) are defined with an increasing potential for victims, be it death and/or injured. The risk classes are defined for a situation where the occupants have to detect the fire by themselves and will react according to their own risk awareness and the available knowledge, including signals and readily accessible information, such as pictograms and instructions. Automatic fire detection and automatic extinguishing systems are not considered at this stage, but included in the protection category. The 5 occupant risk classes can be typified as follows: RCO 1 “Minimal” only applies for areas with few people present and adequate escape possibilities. RCO 2 “Limited” applies in areas where a starting fire can be easily discovered and where people can evacuate with help and guidance from the staff. RCO 3 “Medium” applies for most areas , where standard evacuation procedures are in use, but where some people may need to be rescued. RCO 4 “Increased” applies for areas where a safe evacuation of all people may require fire brigade assistance. RCO 5 “High” applies for areas where a full evacuation of all people may not be practical. Occupant fire risk class and protection categories are linked in the following scheme:

The risk class definition scheme is shown in the following flow sheet:


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Occupant fire risk assessment flow sheet

A. Ignition probability class: defined by occupancy and occasional ignition sources. IGN 0 & IGN 1 : Low IGN 2 - IGN 4 : Medium IGN 5 - IGN 6 : High IGN 6 + : Very High

C. Level of exposure: EX1 very low EX2 low EX3 medium EX4 increased EX5 high EX6 very high

F: Available occupant fire protection: Basic: users of the building can detect a fire, leave the fire scene as necessary and call the fire brigade for help. Category 1: a basic fire safety plan exists and the building has manual fire alarm and fire fighting means. Fire brigade uses standard fire fighting procedures. Category 2: Detailed fire safety plan; the building has an automatic fire detection and alarm system and manual fire fighting means. The fire brigade has a specific fire intervention plan for the building. Category 3: Detailed fire safety plan and the building has an automatic sprinklers and and an occupant alarm system. The fire brigade has established a specific fire intervention plan for the building. Category 4: Detailed fire safety concept including a fire safety plan for the users, a specific fire intervention plan for the fire brigade and manual as well as automatic fire protection systems tailored to the characteristics of the building.

B. Fire growth category: defined by HRR DE1 Slow DE2 Moderate DE3 Average DE4 Fast DE5 Ultra fast

D. Required safe egress time ET1 Awake and familiar with the building ET2a Awake and unfamiliar ET2b Mobile persons needing guidance ET3 Likely to be asleep , familiar with building ET4 Likely to be asleep, unfamiliar with building ET5 Persons with limited mobility ET6 Persons who need individual help for evacuation ET7 Groups larger than 500 persons

E. Occupant fire risk class RCO1 : RCO2: RCO3: RCO4: RCO5:


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Ignition probability class.

The first step of the decision tree defines the ignition potential, i.e. the probability that a fire can start in the compartment. The probability that a fire can start on the premises is defined by the type of occupancy itself and by the level of control of occasional ignition sources. Fire starts where oxygen, combustibles and energy meet. Industrial processes that combine combustible materials and energy consuming machinery (such as woodworking) are more prone to fire than those with wet processes or little use of energy. Storage facilities usually have large fire loads but very few ignition sources, so ignition is there a rather rare event. Occupancies can be classified into the following ignition probability categories :

Occupancy type Ignition probability

1. Non industrial occupancies: offices, residential, assembly, educational IGN 0

2. Industry of non-combustible products IGN 0

3. Most industries, large stores, retail shops IGN 2

4. Industry of combustible products such as paper, wood, petrochemicals IGN 4

5. Warehouses and similar storage IGN 0

Occasional or secondary ignition sources include defects of heating and electrical installations, secondary use of hot points and/or flammable materials and human behaviour. The ignition class shall be increased (e.g. from IC 0 to IC 1) for each of the following aggravating factors:

Aggravating factor: Increase class by

Open flame heat generator in the compartment 1

Heating with gas, without automatic leak detection and shutdown 1

Open flame heating with wood or waste materials 2

Non compliant electrical installation 2

Permanent explosion risk : ATEX zone 0 6

Explosion risk : ATEX zone 1, NEC: Class I Div.1 4

Occasional explosion risk: ATEX Zone 2 NEC: CLASS I DIV.2 area 2

Dust explosion hazard ATEX zones 20/21/22 NEC : Class II area 4

Production of combustible dusts without adequate extraction 2

Painting, spraying or coating with flammable products; use of solvents and flammable glues, etc.; without separation from main activity

4

Idem; In a separated space without dedicated ventilation system 2

Fire hazardous human behaviour (e.g. uncontrollable smokers) 2

The ignition probability classes are grouped as follows: IGN 0 , IGN 1, IGN 2 : Low IGN 3 & IGN 4 : Medium IGN 5 & IGN 6 : High IGN 6 + : Very High


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Fire growth category .

In the second step, the same fire growth category is used as for the property risk assessment.





DE3 Average 250 - 450 kW/m² Moderate to fast burning: for most buildings



Level of exposure

In the 3rd step , the level of exposure is defined by the combination of the ignition probability class and the fire growth category.

ignition probability / fire growth category

DE1 DE2 DE3 DE4 DE5

IGN 0, IGN 1, IGN 2 : Low

EX1: very low

EX2: low EX3:medium EX4: increased

EX5: high

IGN 3 & IGN 4 : Medium

EX2: low EX3:medium EX4: increased

EX5: high EX6: very high

IGN 5 & IGN 6 : High EX3:medium EX4: increased


Out of Scope

IGN 6 + : Very High EX4: increased


Out of Scope Out of Scope

Out of scope: this type of fire situations, where fast growing fires could frequently occur, shall be avoided from the beginning. To emphasize this, they are excluded from the basic qualitative fire risk assessment.

Safe egress time margin.

The probability of fire victims decreases with the margin between the required safe egress time (RSET) and the available safe egress time (ASET). The available safe egress time depends basically on fire growth and on the building characteristics. Fire growth is already included in the exposure level. For the purpose of the FRAME-ini fire risk evaluation, it is assumed that the compartment has the legally required exit capacity, i.e. the number of exits, construction, location and the width of the exits and the travel distances comply with the code requirements10 , so that the building configuration provides adequate escape routes for all occupants in the compartment.

10

FRAME has more elaborate approach including an egress time calculation, so that non compliant situations can also be evaluated.


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The required safe egress time will then be defined by the mobility, risk awareness and self-reliance of the occupants. The following categories are defined:

1. Awake and familiar with the building, e.g. office and industrial premises ET 1

2a. Awake and unfamiliar with the building, e.g. shops, exhibitions, museums, leisure centres, other assembly buildings, etc.

ET 2

2b. Mobile persons needing guidance (e.g. pupils) ET 2

3. Likely to be asleep – familiar with the building (residential) ET 3

4. Likely to be asleep – unfamiliar with the building : hotels, etc. … ET 4

5. Persons with limited mobility (patients, elderly, inmates) ET 5

6. Persons who need individual help for evacuation: bedbound patients, wheelchair users, mentally disturbed , …

ET 6

7. Groups larger than 500 persons11 ET 7

Occupant fire risk class

The egress time category and the level of exposure are combined in the next step to define the occupant fire risk class. Several combinations, which are probably non existent (such as residents in a storage warehouse) have been tagged NA = non applicable. If such situations would occur, a quantified risk assessment is necessary. FRAM-ini or any other basic qualitative risk assessment tool shall not used to define the recommended protection level when the group of occupants that has to evacuate simultaneously exceeds 500 persons. 12 Therefore, the ET 7 category is excluded in the table.

EX1 /ET ET1 ET2 ET3 ET4 ET5 ET6

EX1 : very low RCO 1 RCO 1 RCO 2 RCO 2 RCO 3 RCO 3

EX2 : low RCO 1 RCO 2 RCO 2 RCO 3 RCO 3 RCO 4

EX3 : medium RCO 2 RCO 2 RCO 3 RCO 3 RCO 4 RCO 5

EX4: increased RCO 2 RCO 3 RCO 3 RCO 4 RCO 5 NA

EX5 : high RCO 3 RCO 3 RCO 4 RCO 5 NA NA

EX6 : very high RCO 3 RCO 4 RCO 5 NA NA NA

11

The number of 500 persons is arbitrary. The intent is to exclude situations that need a detailed analysis of the exit capacity from the qualitative risk assessment method. 12

A semi- quantitative assessment can be made with FRAME.


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Available protection level The protection level that is defined previously for the property risk assessment shall be compared with the level needed for the occupant risk class and improved when necessary to obtain and adequate protection for the compartment and its occupants. The adequacy of the available protection level can be verified with the following decision table:

BASIC PROTECTION

Category 1 Category 2 Category 3 Category 4

Risk Class I

minimal recommended Superior Superior Superior

Risk Class II

insufficient necessary recommended Superior Superior

Risk Class III

insufficient insufficient necessary recommended Superior

Risk Class IV

insufficient insufficient insufficient necessary recommended

Risk Class V

insufficient insufficient insufficient insufficient necessary

This table can be transposed in the following graphs : For the property fire risk assessment:

For the occupant fire risk assessment:


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Property risk assessment worksheet

Step 1 : Fire duration :

Type of occupancy total fire load density MJ/m²

check

11. Low fire hazard (LH or light hazard) occupancies 200

12. Offices 400

13. Dwellings 500

14. Schools 200

15. Hospitals 250

16. Hotels 250

21. Ordinary fire hazard with low fire load : EN 12845 class OH1 600 -1500

22. Ordinary fire hazard with medium fire load EN 12845 class OH2 1500 - 2000

23. Ordinary fire hazard with high fire load EN 12845 class OH3 2000 - 2500

24. Ordinary fire hazard with very high fire load EN 12845 class OH4 2500

31. High hazard class EN 12845 class HH1 2500



41. Rack storage above 6 m 6750

Construction type total fire load density MJ/m²

1. Totally Incombustible ( e.g. concrete / steel only) 0

2. Incombustible construction, with max. 10% allowance for combustible construction elements as windows, roof covering, etc.

100

3. Wooden structure finished with incombustible materials. 300

4. Masonry construction with wooden floors and girders 300

5. Incombustible structure, combustible finishing. 1000

6. Totally combustible construction 1500

Total fire load occupancy + construction

Fire duration category Total fire load density MJ/m²

DU0 : Short TFLD ≤ 900 MJ/m²

DU1 : Medium 900 MJ/m² < TFLD ≤ 2300 MJ/m²

DU2 : Long TFLD > 2300 MJ/m²

Step 2 : Fire growth category

Fire growth category Typical HRR Typical content



DE3 Average 250 - 450 kW/m²

Moderate to fast burning: voor most buildings

DE4 Fast 450 - 700 kW/m²

Buildings with predominantly materials like textile, wood, paper, dry food, solid plastics

DE5 Ultra fast 700 -1000 kW/m²

Flammable and highly flammable materials such as expanded plastic packaging, wood dust, flammable liquids


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Step 3 : Fire severity category

Fire duration / Fire growth DU0: Short DU1 : Medium DU2 : Long

DE1 Slow SEV1 : Very low SEV2 : Low SEV3 : Average

DE2 Medium SEV2 : Low SEV3 : Average SEV4 : Increased

DE4 Fast SEV4 : Increased SEV5 : High SEV6 : Very high

DE5 Ultra fast SEV5 : High SEV6 : Very high SEV7 : Extra high

Step 4 : Compartment characteristic score

Characteristic Evaluation criteria Value Score

Floor area: Atot m²

Total floor area in the compartment, including mezzanines, platforms, and similar:

√

=

Access & Frontage

Building only accessible at its narrow side double the value of g

+ 50 % of perimeter accessible for fire fighting 0

less than 50 % of perimeter accessible 2

Level One level building – ground floor only 0

Compartment one level above the access level 4

Compartment located 2 or 3 levels above ground floor

6


10


12

Compartment located above 15th floor level 20

Below ground levels 10

Floor to ceiling

Ceiling height < 3m 2

3m < ceiling height < 6m 1

Ceiling height > 6m 0

Structural fire resistance

R60 or more 0

R30 or more 4

Less than R30 9

Total sum of scores for the compartment characteristics : COM

Step 5: Available fire fighting means:

Characteristic Evaluation criteria Value Score

Responding station of the fire brigade

1. Full time station 24 h/24 7 days/7 8

2. Professional crewed station ( day time crewed, night time retained )

6

3. Retained station (part time professionals) 4

4. Volunteer crewed station 2

First arrival time 1. First fire brigade arrival in less than 10 min 10



4. More than 30 minutes delay 0

Public water distribution and private water supplies for fire fighting

Capacity ≥ 120 m³, adequate distribution network, network static pressure ≥ 5 bar

6

Capacity < 120 m³ or pressure < 5 bar 2

Tanker or mobile pump required 0

Fire fighting means total sum of scores FFM


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Step 6: Fire fighting expediency

Fire brigade access / fire fighting means

CC ≤ 7 easy

7 < CC ≤ 14 limited

12 < CC ≤ 20 difficult

> 20 minimal

FFM ≥ 17 EF4 high EF3 medium EF2 low EF1 very low

17 > FFM ≥ 8 EF3 medium EF2 low EF1 very low

8 > FFM EF2 low EF1 very low

Step 7: Property risk class

Combine the results of step 3 and step 6

fire fighting expediency / fire severity

EF1 Very low

EF2 low

EF3 medium

EF4 high

SEV1 very low RCP III RCP II RCP I RCP I

SEV2 low RCP IV RCP III RCP II RCP I

SEV3 average RCP V RCP IV RCP III RCP II

SEV4 increased NAC RCP V RCP IV RCP III

SEV5 high NAC NAC RCP V RCP IV

SEV6 very high NAC NAC NAC RCP V

NAC : Such situations are not acceptable, preventive measures are needed to reduce the fire severity.

Conclusion 1: Property protection category

BASIC Category 1 Category 2 Category 3 Category 4

RCP I minimal recommended Superior Superior Superior

RCP II insufficient necessary recommended Superior Superior

RCP III insufficient insufficient necessary recommended Superior

RCP IV insufficient insufficient insufficient necessary recommended

RCP V insufficient insufficient insufficient insufficient necessary

Basic: users of the building can detect a fire, leave the fire scene as necessary and call the fire brigade for help. Category 1: a basic fire safety plan exists and the building has manual fire alarm and fire fighting means. Fire brigade uses standard fire fighting procedures. Category 2: Detailed fire safety plan; the building has an automatic fire detection and alarm system and manual fire fighting means. The fire brigade has a specific fire intervention plan for the building. Category 3: Detailed fire safety plan and the building has an automatic sprinklers and and an occupant alarm system. The fire brigade has established a specific fire intervention plan for the building. Category 4: Detailed fire safety concept including a fire safety plan for the users, a specific fire intervention plan for the fire brigade and manual as well as automatic fire protection systems tailored to the characteristics of the building.


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Occupant Risk Assessment worksheet

Step A: Ignition probability class:

Occupancy type: Ignition probability

Check

1. Non industrial occupancies: offices, residential, assembly, educational IGN 0

2. Industry of non-combustible products IGN 0

3. Most industries, large stores, retail shops IGN 2

4. Industry of combustible products such as paper, wood, petrochemicals IGN 4

5. Warehouses and similar storage IGN 0

Aggravating factor: Increase by

Open flame heat generator in the compartment 1

Heating with gas, without automatic leak detection and shutdown 1

Open flame heating with wood or waste materials 2

Non compliant electrical installation 2

Permanent explosion risk : ATEX zone 0 6

Explosion risk : ATEX zone 1, NEC: Class I Div.1 4

Occasional explosion risk: ATEX Zone 2 NEC: CLASS I DIV.2 area 2

Dust explosion hazard ATEX zones 20/21/22 NEC : Class II area 4

Production of combustible dusts without adequate extraction 2

Painting, spraying or coating with flammable products; use of solvents and flammable glues, etc.; without separation from main activity

4

In a separated space without dedicated ventilation system 2

Fire hazardous human behaviour (e.g. uncontrollable smokers) 2

Final score for ignition probability class: IGN 0 - IGN 2 = Low ; IGN 3 & IGN 4 = Medium; IGN 5 - IGN 6 = High; IGN 6 + = Very High

Step B: fire growth category :





DE3 Average 250 - 450 kW/m² Moderate to fast burning: voor most buildings



Step C: the level of exposure:

ignition probability / fire growth category

DE1 DE2 DE3 DE4 DE5

IGN 0 - IGN 2 : Low EX1 EX2 EX3 EX4 EX5

IGN 3 - IGN 4 : Medium

EX2 EX3 EX4 EX5 EX6

IGN 5 - IGN 6: High EX3 EX4 EX5 EX6 Out of Scope

IGN 6 + : Very High EX4 EX5 EX6 Out of Scope Out of Scope

Out of Scope: this type of fire situations, where fast growing fires could frequently occur, shall be avoided from the beginning;


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Step D: Required safe egress time

Awake and familiar with the building, e.g. office and industrial premises ET 1

Awake and unfamiliar with the building, e.g. shops, exhibitions, museums, leisure centres, other assembly buildings, etc.

ET 2

Mobile persons needing guidance (e.g. pupils) ET 3

Likely to be asleep – residential buildings, hotels, etc. … ET 4

Persons with limited mobility (patients, elderly, inmates) ET 5

Persons who need individual help for evacuation: bedbound patients, wheelchair users, mentally disturbed , …

ET 6

Groups larger than 500 persons ET 7

Note: Group ET 7 is excluded from the qualitative risk assessment.

Step E: Occupant fire risk class

Combine the results from steps C and D:

EX1 /ET ET1 ET2 ET3 ET4 ET5 ET6

EX1 : very low RCO 1 RCO 1 RCO 2 RCO 2 RCO 3 RCO 3

EX2 : low RCO 1 RCO 2 RCO 2 RCO 3 RCO 3 RCO 4

EX3 : medium RCO 2 RCO 2 RCO 3 RCO 3 RCO 4 RCO 5

EX4 : high RCO 2 RCO 3 RCO 3 RCO 4 RCO 5 NA

EX5 : very high RCO 3 RCO 3 RCO 4 RCO 5 NA NA

Note: NA means that a qualitative risk assessment is not applicable for these situations.

Conclusion 2 : Occupant fire protection level decision graph.

BASIC Category 1 Category 2 Category 3 Category 4

RCO1 minimal recommended Superior Superior Superior

RCO2 insufficient necessary recommended Superior Superior

RCO3 insufficient insufficient necessary recommended Superior

RCO4 insufficient insufficient insufficient necessary recommended

RCO5 insufficient insufficient insufficient insufficient necessary

Basic: users of the building can detect a fire, leave the fire scene as necessary and call the fire brigade for help. Category 1: a basic fire safety plan exists and the building has manual fire alarm and fire fighting means. Fire brigade uses standard fire fighting procedures. Category 2: Detailed fire safety plan; the building has an automatic fire detection and alarm system and manual fire fighting means. The fire brigade has a specific fire intervention plan for the building. Category 3: Detailed fire safety plan and the building has an automatic sprinklers and and an occupant alarm system. The fire brigade has established a specific fire intervention plan for the building. Category 4: Detailed fire safety concept including a fire safety plan for the users, a specific fire intervention plan for the fire brigade and manual as well as automatic fire protection systems tailored to the characteristics of the building.

Documents

A qualitative fire risk assessment · PDF fileFRAM-ini: A qualitative fire risk assessment method FRAM-ini: A qualitative fire risk assessment method ... Available fire fighting means