NOISE IMPACT ASSESSMENT - Ribble Valley · ‘avoid noise from giving rise to significant adverse impacts on health and quality of life as a result of development; mitigate and reduce

NOISE IMPACT ASSESSMENT

LONGSIGHT ROAD, LANGHO

REC REFERENCE: 90507R1

REPORT PREPARED FOR: HALLAM LAND MANAGEMENT LIMITED

15TH JULY 2014

National Consultancy, Locally Delivered

www.recltd.co.uk

Noise and Vibration Impact Assessment 15th July 2014

Longsight Road, Langho 90507r1

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QUALITY ASSURANCE

REC Offices

Manchester Osprey House Pacific Quay Broadway Manchester M50 2UE Tel: 0161 868 1300

Plymouth Unit 13, Barn Close, Langage Business Park Plymouth Devon PL7 5HQ Tel: 0844 561 6735

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Newcastle Unit 20, Hubway House Bassington Industrial Estate Bassington Lane Cramlington Northumberland NE23 8AD Tel: 0167 0700 927

London 85 Tottenham Court Road London W1T 4TQ Tel: 02034 022 352

Port Talbot Unit 19 Kenfig Industrial Estate Margam Port Talbot SA13 2PE Tel: 01659 749 823

Issue/revision Issue 1 Revision 1 Revision 2

Remarks Draft, for client approval Final, for planning

Date 19th June 2014 15

th July 2014

Prepared by John Goodwin John Goodwin

Qualifications BSc (Hons), MIOA BSc (Hons), MIOA

Signature

Checked by Lee Faulkner Lee Faulkner

Qualifications BSc (Hons), TechIOA BSc (Hons), TechIOA

Signature

Authorised by Paul Furmston Paul Furmston

Qualifications BSc (Hons) BSc (Hons)

Signature

Project number 90507r0 90507r1

Doc. Ref – QR3-3 Issued – Jan -13 By – A Edgar



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EXECUTIVE SUMMARY Noise Surveys

A series of Noise and Vibration Surveys have been completed in order to measure the impact of road and rail traffic upon the proposed residential development and to quantify the existing ambient noise climate in the absence of the proposed shared car park facility.

Noise Impact Assessment

The Noise Impact Assessment has identified that the key noise sources impacting upon the development are from road traffic using the A59 to the north of the Site and from trains using the Manchester to Clitheroe railway line to the south. Accordingly appropriate mitigation has been specified in order to reduce these impacts for both external and internal habitable areas.

The change in ambient noise level brought about by use of the shared car park facility gives a ‘slight’ noise impact at the closest proposed receptor which is considered acceptable.

The Vibration Impact Assessment has identified that the movement of trains does not give rise to vibration levels which exceed the ‘low probability of adverse comment’ criteria.

Recommended Mitigation Measures

The following mitigation measures have been recommended in order to control internal and external noise levels:

An Acoustic fence of 1.9m height should be installed on the garden boundaries and in between dwellings located in Batch A in order to screen garden areas from passing road traffic; and,

A scheme of alternative ventilation will be required for the habitable rooms of dwellings located in Batch A which face the A59 and the habitable rooms which face the railway line. This will permit ventilation into the rooms without the need to open windows.



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TABLE OF CONTENTS

QUALITY ASSURANCE I

EXECUTIVE SUMMARY 2

TABLE OF CONTENTS 3

1.0 INTRODUCTION 4

1.1 Background 4

1.2 Site Location & Proposed Development 4

1.3 Limitations 4

1.4 Confidentiality 4

2.0 ASSESSMENT CRITERIA 5

2.1 National Planning Policy Framework 5

2.2 Local Authority Guidance and Criteria – Ribble Valley Borough Council’s Environmental Health Department 5

2.3 British Standard BS8233: 2014: Guidance on Sound Insulation and Noise Reduction for Buildings 6

2.4 World Health Organisation’s (WHO) ‘Guidelines for Community Noise’ 6

2.5 IEMA/IOA Draft Guidelines for Noise Impact Assessment, 2002 7

2.6 British Standard BS 6472: 2008: Evaluation of Human Exposure to Vibration in Buildings (1Hz to 80Hz) 7

3.0 NOISE & VIBRATION SURVEYS 9

3.1 Road Traffic Noise Survey – A59 9

3.2 Rail Traffic Noise Survey 10

3.3 Ambient Noise Survey 11

3.4 Rail Traffic Vibration Survey 11

3.5 Car Parking Source Noise – Library Data 12

4.0 NOISE IMPACT ASSESSMENT 13

4.1 Road Traffic Noise – A59 13

4.1.1 External Amenity Areas 14

4.1.2 Internal Amenity Areas 14

4.2 Rail Traffic Noise Assessment 15

4.2.1 Rail Traffic Noise Impact Assessment – External Amenity Areas 16

4.2.2 Rail Traffic Noise Impact Assessment – Internal Habitable Rooms 17

4.3 Shared Car Park Facility 19

4.4 Rail Traffic Vibration Impact Assessment 20

5.0 MITIGATION 21

5.1 Road Traffic Noise – A59 21

5.2 Rail Traffic Noise 22

6.0 CONCLUSION 23

APPENDICES

Appendix I Limitations Appendix II Glossary of Acoustic Terminology Appendix III Figures



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1.0 INTRODUCTION 1.1 Background Resource and Environmental Consultants (REC) Limited have been commissioned by Hallam Land Management Limited to undertake a Noise and Vibration Impact Assessment for a proposed residential-led development on land located off Longsight Road in Langho, Lancashire to be referred to hereafter as ‘the Site’.

This assessment has been undertaken to identify key noise and vibration sources in the vicinity of the Site which may have the potential to impact upon the proposed noise and vibration sensitive residential development. This Noise and Vibration Impact Assessment has been completed with due regard to the requirements of Ribble Valley Borough Council’s Environmental Health Department. All acronyms used within this report are defined in the Glossary presented in Appendix II. 1.2 Site Location & Proposed Development The Site comprises a parcel of land currently comprising of open land. The A59 lies to the north, existing residential dwellings and Northcote Road to the east and the Manchester to Clitheroe railway line to the south. To the west lies open land.

The key sources of noise impacting upon the Site are from road traffic using the A59 and trains using the railway line to the south.

Proposals include for the construction of 132 dwellings and a small shared car park facility scheme to service Langho railway station.

This assessment has been undertaken with due regard to the supplied Site plan contained in Figure 1 of Appendix III.

1.3 Limitations The limitations of this report are presented in Appendix I. 1.4 Confidentiality REC has prepared this report solely for the use of the Client and those parties with whom a warranty agreement has been executed, or with whom an assignment has been agreed. Should any third party wish to use or rely upon the contents of the report, written approval must be sought from REC; a charge may be levied against such approval.



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2.0 ASSESSMENT CRITERIA 2.1 National Planning Policy Framework The National Planning Policy Framework (NPPF) provides very brief guidance on planning and noise. The NPPF replaces the now revoked Planning Policy Guidance (PPG) Note 24. Paragraph 123 of the NPPF document states that planning policies and decisions should aim to:

‘avoid noise from giving rise to significant adverse impacts on health and quality of life as a result of development;

mitigate and reduce to a minimum other adverse impacts on health and quality of life arising from noise from new development, including through the use of conditions;

recognise that development will often create some noise and existing businesses wanting to develop in continuance of their business should not have unreasonable restrictions put on them because of changes in nearby land uses since they were established; and,

Identify and protect areas of tranquillity which have remained relatively undisturbed by noise and are prized for their recreational and amenity value for this reason.’

This has been considered throughout the assessment where applicable. No further guidance is given as to what a ‘significant’ impact would entail. It is therefore considered that meeting the criteria outlined in BS 8233 and recommendations contained within the World Health Organisation guidelines, “significant adverse impacts” on health and quality of life associated with noise would be avoided. 2.2 Local Authority Guidance and Criteria – Ribble Valley Borough Council’s Environmental Health Department REC contacted Heather Coar, EHO at Ribble Valley Borough Council in April 2014 in order to agree the methodology for the noise and vibration surveys and the appropriate noise criteria for this assessment. The following criteria were agreed:

The maximum permissible average noise level in garden areas shall not exceed 55dB LAeq,16hr for gardens which lies close to the A59, with 50dB LAeq,16hr being applicable for the remainder of garden areas. This method was proposed in order to minimise acoustic fence heights which front the development along the boundary with the A59;

The maximum permissible average noise level in living rooms shall not exceed the

BS8233:2014 internal target criteria which is 35dB LAeq,16hr;

The maximum permissible average noise level in bedrooms shall not exceed the BS8233:2014 internal target criteria which is 30dB LAeq,8hr; and,

The maximum permissible instantaneous noise level in bedrooms shall not exceed 45dB

LAmax,fast criteria.



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2.3 British Standard BS8233: 2014: Guidance on Sound Insulation and Noise Reduction for Buildings The scope of this standard is the provision of recommendations for the control of noise in and around buildings. It suggests appropriate criteria and limits for different situations, which are primarily intended to guide the design of new buildings or refurbished buildings undergoing a change of use, rather than to assess the effect of changes in the external noise climate. The standard suggests suitable internal noise levels within different types of buildings, including dwellings, as shown in Table 2.1: Table 2.1: BS8233 Recommended Internal Noise Levels

Criterion Typical Situation Design LAeq,T

(dB)

Suitable resting / sleeping conditions

Living Room 35

Bedroom 30

For a reasonable standard in bedrooms at night, individual noise events (measured with fast time weighting) should not normally exceed 45dB LAmax

BS8233 goes on to recommend noise levels for gardens. According to BS8233;

“It is desirable that the external noise level does not exceed 50dB LAeq,T, with an upper guideline value of 55dB LAeq,T which would be acceptable in noisier environments.

However, it is also recognised that these guideline values are not achievable in all circumstances where development might be desirable. In higher noise areas, such as city centres or urban areas adjoining the strategic transport network, a compromise between elevated noise levels and other factors might be warranted”.

BS8233 goes on to say:

“In such a situation, development should be designed to achieve the lowest practicable levels in these external amenity spaces, but should not be prohibited”.

2.4 World Health Organisation’s (WHO) ‘Guidelines for Community Noise’ The WHO gives guidance on desirable levels of environmental noise. The levels presented in the WHO Community Guidelines are those at which adverse effects become measurable. The 1980 WHO document suggested that "general daytime outdoor noise levels of less than 55dB(A) Leq,16hr are desirable to prevent any significant community annoyance" This level is an external free-field noise level. The 1980 document also stated in relation to internal levels "that night-time noise levels of 35dB(A) Leq,8hr or less will not interfere with the restorative process of sleep". A report was submitted to the WHO in 1995 for consideration as a revision to the 1980 document and revised community guidelines were issued in 2000. In the 2000 guidelines, it is considered that the sleep disturbance criteria should be taken as an internal noise level of 30dB LAeq,8hr or an external level of 45dB LAeq,8hr. It also recommends that internal LAmax levels of 45dB and external LAmax levels of 60dB should be limited where possible.



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The 2000 WHO document also states that "To protect the majority of people from being seriously annoyed during the daytime, the sound pressure level on balconies, terraces and outdoor living areas should not exceed 55dB LAeq,16hr for a steady continuous noise." i.e. the daytime levels effectively remain unchanged. 2.5 IEMA/IOA Draft Guidelines for Noise Impact Assessment, 2002 Although the Institute of Environmental Management Assessment (IEMA)/Institute of Acoustics (IOA) Working Party guidelines (IEMA/IOA, 2002) are still only a consultation draft at this stage, they are of some assistance in this exercise. The Working Party provides an example of how changes in noise level can be categorised by significance as detailed in Table 2.2. Table 2.2: Example of Categorising the Ambient Noise Level Change

Noise Change (dB)

Category

0 No Impact

0.1 – 2.9 Slight Impact

3.0 – 4.9 Moderate Impact

5.0 – 9.9 Substantial Impact

10.0+ Severe Impact

2.6 British Standard BS 6472: 2008: Evaluation of Human Exposure to Vibration in Buildings (1Hz to 80Hz) With respect to human exposure to vibration in building, BS 6472 provides guideline values of the vibration dose value (VDV) above which various degrees of adverse comment may be expected from the occupants of residential buildings. The VDV is defined mathematically as the fourth root of the time integral of the fourth power of the acceleration, after it has been frequency weighted. The guideline values recommended by BS 6472 are shown in Table 2.3 below. Table 2.3: BS 6472 Guideline Values

Place Low Probability of Adverse Comment

Adverse Comment Possible

Adverse Comment Probable

Residential Buildings (16 Hour Day)

0.2 – 0.4 0.4 – 0.8 0.8 – 1.6

Residential Buildings (8 Hour Night)

0.1 – 0.2 0.2 – 0.4 0.4 – 0.8

Where the is intermittent rather than continuous in nature, BS 6472 defines procedures for calculating the estimated Dose Value (eVDV), based on the number and duration of events and the recorded value of the root mean square frequency weighted acceleration. The frequency weighting takes into account the response of the human body to vibrations of different frequency and whether the person is lying down or standing. The eVDV can then be taken as the VDV for use in the assessment of human exposure to vibration in buildings.



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The above guidance relates to vibration measured at the point of entry into the human body, which is usually taken to mean the ground surface or at a point mid-span of an upper storey floor, rather than the point of entry into the building (a foundation element).



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3.0 NOISE & VIBRATION SURVEYS REC has conducted a series of Noise and Vibration Surveys which included:

Road Traffic Noise Survey for the A59 to the north;

Rail Traffic Noise Survey for the Manchester to Clitheroe Railway Line to the south of the

Site;

Ambient Noise Survey, in order to measure the existing ambient noise climate at a location considered representative of closest existing and proposed residential receptors to the proposed shared car park facility; and,

Rail Traffic Vibration Survey for the Manchester to Clitheroe Railway Line to the south of

the Site. 3.1 Road Traffic Noise Survey – A59

REC has conducted a Road Traffic Noise Survey in order to measure the level of noise generated by vehicles using the A59. The survey was carried out over the following time period:

Wednesday 19th February 2014 between 10:10 and 13:00.

The following noise measurement position was chosen for the Road Traffic Noise Survey:

Noise Measurement Position 1 (NMP1): Located on the eastern site boundary, 4m from the nearside kerbstone of the A59. The microphone was located 1.5m above ground level and in free-field conditions. Noise sources at this location consisted predominately of vehicle pass-bys on the A59.

A summary of the measured sound pressure levels from the Road Traffic Noise Survey are presented in Table 3.1. Table 3.1: Summary of Measured Noise Levels for NMP1

Measurement Position

Period

Measured Sound Pressure Level, free-field (dB)

LAeq,T LAmax,fast1 LA90,T LA10,T

NMP1

19/02/2014 10:00 – 11:00

72.5

84.5

53.6 76.5

19/02/2014 11:00 – 12:00

72.3 54.4 76.2

19/02/2014 12:00 – 13:00

71.7 52.1 75.6

1 10

th highest LAmax,fast from three 1-hour periods



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3.2 Rail Traffic Noise Survey REC has conducted a Rail Traffic Noise Survey in order to measure the level of noise generated by trains using the Manchester to Clitheroe Railway Line. The survey was carried out over the following time periods:

Passenger Trains - 19th February 2014 between 10:51 and 13:05; and,

Freight Trains – 26th March 15:52.

The following noise measurement position was chosen for the Rail Traffic Noise Survey:

Noise Measurement Position 2 (NMP2): Located on the southern boundary, 8m from the centre of the track. The microphone was located 1.5m above ground level and in free-field conditions. Noise sources at this location consisted predominately of intermittent train pass-bys.

A summary of the measured sound pressure levels from the Rail Traffic Noise Survey are presented in Table 3.2 for Northern commuters and Freight. The Calculated Sound Event Level for each train pass-by has been calculated using the following formula:

SEL = LAeq + 10 x Log t

Where: t = time in seconds

Table 3.2: Summary of Measured Noise Levels for NMP3 for Northern Commuters & Freight

Type Direction

Measured Sound Pressure Level (dB) Measurement

Duration (seconds)

Calculated SEL (dB)

LAeq,T LAmax,fast

Passenger – Northern Rail

East to West 57.2 62.5 29 71.8

East to West 52.4 56.5 20 65.4

East to West 54.7 57.9 17 67.0

West to East 58.3 65.5 88 77.7

West to East 59.8 66.8 66 78.0

West to East 60.9 67.2 73 79.5

Freight West to East 76.5 87.7 50 93.5



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3.3 Ambient Noise Survey REC has conducted an Ambient Noise Survey in a position considered representative of the existing ambient noise climate at the closest existing and proposed residential dwellings to the proposed shared car park facility. Table 3.3: Summary of Lowest Measured 1-hr Ambient Noise Levels

Period Lowest Measured Ambient Noise Level

LAeq,T

(dB)

Daytime 47.3

Night-time 41.6

The following equipment was used for the Noise Surveys. Table 3.4: Noise Measurement Equipment


Equipment Description

Manufacturer & Type No.

Serial No. Calibration Due

Date

NMP1 - 3

Sound Level Meter 01dB-Metravib Black

Solo 65211

24th

April 2015 Pre-amplifier 01dB-Metravib PRE

21 S 15766

Microphone 01dB Metravib

MCE212 142644

Calibrator 01dB-Metravib CAL-

21 34113643 1

st April 2015

The sound level meters were field-calibrated on Site prior to and after noise measurements were taken. No significant drift was witnessed. Calibration certificates are available upon request. 3.4 Rail Traffic Vibration Survey REC has conducted a Rail Traffic Vibration Survey in order to measure the level of vibration associated with the different train types which use the Manchester to Clitheroe Railway Line. The survey was carried out over the following time period:

Wednesday 29th January 2014 between 10:30 and 12:23.

The following vibration measurement position was chosen for the Rail Traffic Vibration Survey:

Vibration Measurement Position 1 (VMP1): The geophone of the Vibration Meter was located 8m from the centre of the railway line. The geophone was located on soft ground and was secured using spikes attached to the geophone to prevent movement.

The measured Peak Particle Velocity (PPV) vibration levels have been weighted in accordance with the guidance stated in BS6472, where the Wb weighting is applied to the vertical axis (z axis) and the Wd weighting is applied to the horizontal axes (x and y axes). A summary of the measured weighted vibration levels from the vibration survey are presented in Table 3.5.



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Table 3.5: Measured Peak Particle Velocity Vibration Levels for all Train Providers

Provider/Type Time

Measured Vibration Level, by Axis (mm/s)

X Axis Y Axis Z Axis

Northern/ Commuter

14:48 0.635 0.508 0.381

15:00 0.381 0.381 0.508

15:01 0.381 0.381 0.762

Note: Vibration measurements for Freight train not available due to irregularity of movements

The Rail Traffic Vibration Survey was completed using the following specification vibration measurement equipment shown in Table 3.6. Table 3.6: Vibration Measurement Equipment


Equipment Description

Manufacturer & Type No.

Serial No. Calibration Due

Date

VMP1

Vibration Meter Instantel Blastmate III BA18274

13th

April 2015

Tri-axial Geophone Instantel Geophone BG17363

3.5 Car Parking Source Noise – Library Data REC has used historic library data of a passenger vehicle in order to inform the Car Parking Noise Assessment (change in ambient noise levels). A summary of the measured sound pressure levels from the car source noise survey are presented in Table 3.7. Table 3.7: Summary of Measured Noise Levels for Car Source Noise Survey

Scenario Measurement

Duration (mm:ss)

Sound Pressure Level (dB)

Measured LAeq,T

(dB)

Measured LAmax,fast

(dB)

Calculated Sound

Exposure Level (dB)

The passenger vehicle drives into a car parking space, the engine is turned off

followed by one car door slam (Average measurement distance 5m)

00:32 49.9 67.1 65.0

One car boot slam followed by one car door slam. Vehicle starts and drives off.

(Average measurement distance 5m) 00:24 57.4 69.9 71.2



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4.0 NOISE IMPACT ASSESSMENT 4.1 Road Traffic Noise – A59 For the purposes of this assessment, the daytime and night-time average (Leq,T) noise levels have been calculated based on the shortened measurement procedure detailed in CRTN. The respective daytime and night-time noise levels have been derived using the following calculations:

1. Calculation of the LA10,18hr noise level by using the following formula: L10,18hr = L10,3hr – 1dB

2. Calculation of the LAeq,16hr noise level by using the following formula: Leq,16hr = L10,18hr – 2dB 3. Calculation of the night-time LAeq,8hr noise level by using the following formula:

Lnight (Leq,8hr) = 0.90 x L10,18hr – 3.77dB Table 4.1 displays the calculated daytime average and night-time average and maximum noise levels. Table 4.1: Calculation of Daytime and Night-time Road Traffic Noise Levels


Period Calculated LAeq

(dB)

10th

Highest Measured LAmax,fast

(dB)

Measurement Distance from

Centre of A59 (m)

NMP1

Daytime (07:00 – 23:00)

73.1 -

7.5 Night-time

(23:00 – 07:00) 63.8 84.5

1 10

th highest LAmax,fast from three 1-hour periods

In determining the level of noise impact at the various dwellings, the following equation has been used to determine the resulting noise level from the daytime and night-time ‘average’ noise levels:

LAeq,2 = LAeq,1 – (10 x log (D2/D1) Where LAeq,2 = noise level under investigation LAeq,1 = measured noise level D2 = distance under investigation D1 = measurement distance

The following equation has been used to determine the resulting noise level from the night-time measured maximum noise level: LAmax,fast,2 = LAmax,fast,1 – (20 x log (D2/D1) Where LAmax,fast,2 = noise level under investigation LAmax,fast,1 =measured noise level D2 = distance under investigation D1 = measurement distance



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The following equation has been used to account for soft-ground coverage between source and receiver: Correction = 5.2 LOG10 (3 / (d + 3.5)) Where d = distance from edge of nearside carriageway

The closest residential dwellings to the A59 have been assessed as these are considered worst affected by road traffic noise. In principle, these dwellings will form an acoustic barrier block to the dwellings behind thus negating the need for noise mitigation measures across the remainder of the development. For the purposes of this assessment, the closest dwellings have been termed ‘Batch A’. 4.1.1 External Amenity Areas Table 4.2 details the calculated daytime noise levels for the nearest external amenity areas to the A59 using a noise measurement distance of 8.5m from the centre of the A59. Table 4.2: Calculation of Daytime Outdoor Garden Noise Levels

Batch

Calculated Daytime LAeq,16hr

(dB)

Distance to Garden

(m)

Soft Ground Attenuation

(dB)

Calculated Noise Level in Garden

(dB)

Noise Criteria Level (dB)

Difference +/- (dB)

A 73.1 44 -5.1 61.4 55 +6.4

Table 4.2 indicates that the daytime noise level from road traffic in the garden areas of Batch A exceed the outdoor noise criteria level. Accordingly the following Section will consider appropriate mitigation in order to reduce these exceedences. 4.1.2 Internal Amenity Areas In addition to noise levels in garden areas, it is necessary to consider internal noise levels within habitable rooms. Table 4.3 details the calculated noise levels for the facades of the dwellings that have line of sight to the A59 using the measurement distance of 8.5m. Table 4.3: Calculation of Noise Levels at the Facade

Batch Period Measured Noise

Level (dB)

Distance to Façade

(m)

Soft Ground Correction

(θ)

Calculated External Noise Level at Façade

(dB)

A

Daytime 67.7 LAeq,16hr

34 -5.6

61.0

Night-time

59.0 LAeq,8hr 51.7

78.5 LAmax,fast 65.8

The now revoked Planning Policy Guidance Note (PPG24) suggests that the sound reduction index afforded by such glazing set in a standard brick block wall will reduce road traffic external to internal noise levels by approximately 33dB. Table 4.4 calculates the internal noise level using standard thermal double glazing. Any exceedences are highlighted in bold.



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Table 4.4: Calculation of Internal Noise Levels with Standard Thermal Double Glazing

Dwelling Period

Calculated External

Noise Level (dB)

Attenuation Afforded by

Standard Thermal Double Glazing

(dB)

Calculated Internal Noise

Level (dB)

Criteria Noise Level (dB)

Difference -/+ (dB)

1

Daytime 61.0 LAeq,16hr 33 28.0 35 -7.0

Night-time

51.7 LAeq,8hr 33 18.7 30 -11.3

65.8 LAmax,fast 33 32.8 45 -12.2

Table 4.4 indicates that standard thermal double glazing will be sufficient for habitable rooms which face the A59. During summer months it may be necessary to open windows in order to provide a supply of fresh air to cool the habitable room. Table 4.5 determines the internal noise levels for proposed dwellings along the southern boundary. BS8233 suggests that the sound reduction index of a partially open window will attenuate noise by approximately 10dB – 15dB and so this assessment has adopted 12dB. Table 4.5: Calculation of Internal Noise Levels with a Partially Open Window

Dwelling Period

Calculated External

Noise Level (dB)

Attenuation Afforded by a

Partially Open

Window (dB)


Level (dB)

Criteria Noise Level (dB)

Difference -/+ (dB)

1

Daytime 61.0 LAeq,16hr 12 49.0 35 +14.0

Night-time

51.7 LAeq,8hr 12 39.7 30 +9.7

65.8 LAmax,fast 12 53.8 45 +8.8

Table 4.5 indicates that the internal target noise levels will be exceeded for all habitable rooms which face the A59 and so the following section considers alternative ventilation to opening windows. 4.2 Rail Traffic Noise Assessment The measured noise levels for the train pass-bys have been converted to the 16-hour daytime noise level by using the following equation: LAeq,16hr = Average SEL – (10 x log (60 x 60 x 16) + 10 x log N Where Average SEL = Average Sound Event Level for Train Type / Provider 60 x 60 x 16 = No. seconds in a 16-hour daytime period N = No. Train pass-bys in a 16 hour daytime period

The measured noise levels for the train pass-bys have been converted to the 8-hour night-time noise level by using the following equation:



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LAeq,8hr = Average SEL – (10 x log (60 x 60 x 8) + 10 x log N Where Average SEL = Average Sound Event Level for Train Type / Provider 60 x 60 x 8 = No. seconds in a 8-hour night-time period N = No. Train pass-bys in an 8- hour night-time period

The total number of train pass-bys has been obtained using internet-based train timetables. Table 4.6 details the calculated daytime and night-time noise levels for all the train operators. Table 4.6: Determination of Noise Levels – All Trains at 8m

Provider Direction

Average Calculated

SEL (dB)

Average Pass-by

(Measurement) Duration (mm:ss)

Timetabled Movements

Calculated Average Noise Level LAeq,T

(dB)

Day Night Day Night

Northern

East-West 68.1 22 18 2

43.8 34.2

West-East 78.4 75.7 18 2

Freight West-East 93.5 50 7 0 54.3 -*

*No Freight Trains were observed to run during night-time periods and consultation with Freightmaster indicates that this observation is confirmed

Table 4.7 summarises the calculated daytime and night-time noise levels for all train providers. Table 4.7: Determination of Daytime and Night-time Noise Levels – All Train Providers

Provider

Daytime Noise Level

LAeq,16hr (dB)

Night-time Noise Level

LAeq,8hr (dB)

Total Daytime Noise Level

LAeq,16hr (dB)

Total Night-time Noise Level

LAeq,8hr (dB)

10th

Highest LAmax,fast

(23:00 – 07:00) (dB)

Northern 43.8 34.2

54.7 34.2 66.5

Freight 54.3 -

4.2.1 Rail Traffic Noise Impact Assessment – External Amenity Areas In order to accurately calculate the noise level within gardens, calculation has allowed for the following:

1. Distance attenuation from the centre of the railway line to the centre of the garden area by using the following formula:

LAeq,2 = LAeq,1 – (10 x log (D2/D1) Where LAeq,2 = noise level under investigation LAeq,1 = measured noise level D2 = distance under investigation (m) D1 = measurement distance (m)



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Table 4.8 compares the predicted daytime noise levels in the garden area to the railway line with the adopted criteria noise level of 50dB LAeq,16hr for external amenity areas. In determining the noise level within the closest garden areas, the calculation has used the middle point of the railway line which is 8m from the measurement position. The Total Daytime Noise Level LAeq,16hr at 8m was used to calculate the level in the garden area. Table 4.8: Comparison of Predicted Garden Noise Levels with External Target Noise Level

Distance to Garden from Centre of

Railway Line (m)

Calculated Daytime Noise Level

LAeq,16hr (dB)

Adopted Criteria Noise Level (dB)

Difference +/- (dB)

28 49.2 50.0 -0.8

Table 4.8 indicates that the closest garden areas will not exceed the adopted noise criteria level. The above calculations are considered worst-case as they do not include for partial or full line of sight afforded by proposed intervening buildings between the garden and the railway line. 4.2.2 Rail Traffic Noise Impact Assessment – Internal Habitable Rooms In order to accurately determine the noise level within habitable rooms, it has been necessary to calculate the external noise level immediately outside the façade. Accordingly calculation has allowed for the following:

1. Distance attenuation from the centre of the railway line to the façade by using the following formula:

LAeq,2 = LAeq,1 – (10 x log (D2/D1) Where LAeq,2 = noise level under investigation LAeq,1 = measured noise level D2 = distance under investigation (m) D1 = measurement distance (m)

2. The following equation has been used to determine the resulting noise level from the

night-time measured maximum noise level from the railway line: LAmax,fast,2 = LAmax,fast,1 – (20 x log (D2/D1) Where LAmax,fast,2 = noise level under investigation LAmax,fast,1 =measured noise level D2 = distance under investigation (m) D1 = measurement distance (m)



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Table 4.9 calculates the noise levels as a result of rail traffic at the facades of the closest dwellings. Table 4.9: Calculation of Rail Traffic Noise at Facades

Calculated Noise Levels (dB)

Period Distance from Centre of Railway Line to Façade

(m)

Calculated Noise Level at Façade

(dB)

54.7 LAeq,16hour Daytime

(07:00-23:00)

15

52.0

34.2 LAeq,8hour Night-time

(23:00-07:00)

31.5

66.5 LAmax,fast 61.0

In calculating the internal noise levels, the now revoked PPG24 states that standard thermal double glazing, when set into a brick-block wall, will attenuate noise levels from diesel trains by 32dB and this level has been used in the calculations. Table 4.10: Comparison of Calculated Internal Noise Levels with Internal BS8233 Noise Criteria – Windows Closed

Calculated Noise Level at

Façade

(dB)

Period


Standard Thermal Double

Glazing (dB)


Level (dB)

BS8233 ‘Good’ Internal Noise Criteria Level

LAeq,T

(dB)

Difference +/- (dB)


(07:00–23:00) 32 20.0 35 -15.0


(23:00–07:00)

32 -0.5 30 -30.5

69.6 LAmax,fast 32 29.0 45 -16.0

Table 4.10 indicates that all habitable rooms facing the railway line will meet the internal target noise criteria. During summer months it may be necessary to open windows in order to provide a supply of fresh air and Table 4.11 determines the internal noise levels for the dwellings closest to the railway line. BS8233 suggests that the sound reduction index of a partially open window will attenuate noise in the order of 10 – 15dB and so this assessment has used 12dB. Table 4.11: Comparison of Calculated Internal Noise Levels with Internal BS8233 Noise Criteria – Windows Open

Calculated Noise Level at

Façade

(dB)

Period


Partially Open Window

(dB)


Level LAeq,T

(dB)

BS8233 ‘Good’

Internal Noise Criteria Level

LAeq,T

(dB)

Difference +/-

(dB)


(07:00–23:00) 12 40.0 35 +5.0


(23:00–07:00) 12 19.5 36 -16.5



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69.6 LAmax,fast 12 49.0 36 +13.0

Table 4.11 indicates that the BS8233 internal criteria noise levels will be exceeded if windows are opened for the habitable rooms that overlook the railway line and so Section 5 will consider alternative ventilation to opening windows. 4.3 Shared Car Park Facility In undertaking this assessment, REC have allowed for the following assumptions in the calculations:

1. In determining the noise impact at the closest proposed residential dwelling and in the interest of making the assessment worst-case, it has been assumed that all 28 car parking spaces will be occupied and the centre point of the car park has been taken as the average; and,

2. The combined Sound Exposure Levels (SELs) from vehicles driving in and out of car

parking spaces have been used in this assessment. Table 4.12 details the total 1-hour noise level predicted for the closest proposed receptor. Table 4.12: Calculated 1 Hour Noise Level at Each Receptor

Receptor Calculated

Combined SEL (dB)

Calculated Adjusted SEL for Total Car Parking Spaces

(dB)

Distance from Centre of Car Park

to Closest Proposed Receptor

(m)

Calculated 1hr LAeq at Receptor

(dB)

Closest Proposed Receptor

72.1 86.6

(28 Vehicles) 20 39.0

Table 4.13 compares the calculated noise levels at both receptors with the lowest existing measured ambient noise levels. Table 4.13: Comparison of the Calculated 1 Hour Noise Level with the Lowest Measured Ambient Noise Level

Receptor Period

Measured Existing

Ambient Noise Level LAeq

(dB) (A)

Calculated Noise Level LAeq

(dB) (B)

Total Combined Calculated Noise Level

(dB) (C)

(A+B)

Noise Level Change +/-

(dB) (C-A)


Weekday Day

47.3

39.0

47.9 +0.6

Weekday Night

41.6 43.5 +1.9

Table 4.13 categorises the ambient noise level change in accordance with the IEMA/IOA Working Party guidelines (IEMA/IOA, 2002).



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Table 4.13: Comparison of Noise Level Change with Guidance

Receptor Period Noise Level Change

+/- (dB)

Category


Weekday Day

+0.6 Slight Impact

Weekday Night

+1.9 Slight Impact

Table 4.14 indicates that the change in ambient noise level is categorised as ‘slight impact’ which is considered acceptable and requires no consideration of mitigation measures. 4.4 Rail Traffic Vibration Impact Assessment The total VDV for the daytime period and night-time period, for passenger commuter trains and freight trains has been calculated in accordance with the methodology presented in BS6472: 2008 using the appropriate weightings. The total number of commuter and freight trains has been obtained from train timetables published on the internet. Table 4.14 below summarises the results of the vibration assessment. Table 4.14: Summary of Predicted Vibration Levels

Train Type

Timetabled Train Movements Predicted Vibration Dose Value (m/s

1.75)

Daytime (07:00 – 23:00)

Night-time (23:00 – 07:00)

Daytime (07:00 – 23:00)

Night-time (23:00 – 07:00)

Passenger 36 4 0.032 0.000

Freight 7 0 0.040 0.023

Total: 0.044 0.023

Comparing the predicted VDV levels at the Site boundary with the railway, and with the guideline values from BS6472:2008, it can be seen that there is less than a low probability of adverse comment likely.



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5.0 MITIGATION 5.1 Road Traffic Noise – A59 5.1.1 External Amenity Areas The previous section has indicated that the noise level in certain garden areas exceeds the criteria level and the most appropriate method for controlling noise in garden areas is by use of an acoustic-grade fence. Table 5.1 details the required height of the acoustic fence for Batch A. In calculating the height of the acoustic fences, the following have been accounted for:

Source height has been taken as 0.5m above local ground level; and,

Receiver height has been taken as being 1.8m above local ground level accounting for a 1.8m high person stood in the centre of the garden area.

Table 5.1: Calculation of Acoustic Fence Heights

Garden Area

Exceedence of Criteria without Acoustic Fence

+/- (dB)

Corresponding Path Difference

(m)

Required Fence Height to Meet Criteria

(m)

Batch A +6.4 0.01 1.9

Table 5.1 indicates that an acoustic fence of 1.9m height will be required to be installed around the outer garden areas of the dwellings in Batch A and between dwelling plots. The barrier should prevent line of sight to the A59 from a person stood in any of the garden areas within Batch A. The precise location of these fences is shown on Figure 2 of Appendix III. The fences should have a minimum mass of 28kg/m

2 and be free from holes.

5.1.2 Internal Amenity Areas The previous section indicated that with a partially open window, the internal noise levels for any habitable rooms within Batch A which have line of sight to the A59 will exceed the internal target criteria. Accordingly, It is recommended that a through-frame window mounted trickle ventilator is incorporated into the glazing unit of the habitable rooms so that fresh air can enter the room without having to open windows. One such acoustic trickle ventilator is as follows:

Greenwoods EAR42W Trickle Ventilator, which provides acoustic attenuation of up to 42 dB Dn,e,w + Ctr in its open position.

The trickle ventilator should be combined with a Mechanical Extract Ventilation (MEV), a Mechanical Ventilation Heat Recovery (MVHR) or a Passive Extract Ventilation (PEV) system which extracts air from the habitable rooms. Wherever possible habitable rooms should be located away from the noise source with less noise-sensitive rooms facing the noise source.



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5.2 Rail Traffic Noise 5.2.1 Internal Amenity Areas The previous section indicated that with a partially open window, the internal noise levels for any habitable rooms which have line of sight to the railway line will exceed the internal target criteria. Accordingly, it is recommended that a through-frame window mounted trickle ventilator is incorporated into the glazing unit of the habitable rooms so that fresh air can enter the room without having to open windows. One such acoustic trickle ventilator is as follows:

Greenwoods EAR42W Trickle Ventilator, which provides acoustic attenuation of up to 42 dB Dn,e,w + Ctr in its open position.

The trickle ventilator should be combined with a Mechanical Extract Ventilation (MEV), a Mechanical Ventilation Heat Recovery (MVHR) or a Passive Extract Ventilation (PEV) system which extracts air from the habitable rooms. Wherever possible habitable rooms should be located away from the noise source with less noise-sensitive rooms facing the noise source.



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6.0 CONCLUSION REC Limited have been commissioned by Hallam Land Management Limited to undertake a Noise and Vibration Impact Assessment for a proposed residential-led development on land located off Longsight Road in Langho, Lancashire.

This assessment has been undertaken to identify key noise and vibration sources in the vicinity of the Site which may have the potential to impact upon the proposed noise and vibration sensitive residential development. This Noise and Vibration Impact Assessment has been completed with due regard to the requirements of Ribble Valley Borough Council’s Environmental Health Department. The Noise Impact Assessment has identified that the key noise sources impacting upon the development are from road traffic using the A59 to the north of the Site and from trains using the Manchester to Clitheroe railway line to the south. Accordingly appropriate mitigation has been specified in order to reduce these impacts for both external and internal habitable areas.

The change in ambient noise level brought about by use of the shared car park facility gives a ‘slight’ noise impact at the closest proposed receptor which is considered acceptable.

The Vibration Impact Assessment has identified that the movement of trains does not give rise to vibration levels which exceed the ‘low probability of adverse comment’ criteria.

It should be noted that all of the calculations performed in this assessment are based on worst-case assumptions and so the actual level of noise within external amenity areas and internal habitable rooms is likely to be lower than the calculated noise levels. Subject to the incorporation of the identified mitigation measures it is considered that the Site is suitable for the promotion of residential development.



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1. This report and its findings should be considered in relation to the terms of reference and objectives agreed between REC Limited and the Client as indicated in Section 1.2.

2. The executive summary, conclusions and recommendations sections of the report provide an overview and

guidance only and should not be specifically relied upon without considering the context of the report in full. 3. REC cannot be held responsible for any use of the report or its contents for any purpose other than that for

which it was prepared. The copyright in this report and other plans and documents prepared by REC is owned by them and no such plans or documents may be reproduced, published or adapted without written consent. Complete copies of this may, however, be made and distributed by the client as is expected in dealing with matters related to its commission. Should the client pass copies of the report to other parties for information, the whole report should be copied, but no professional liability or warranties shall be extended to other parties by REC in this connection without their explicit written agreement there to by REC.



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Noise

Noise is defined as unwanted sound. Human ears are able to respond to sound in the frequency range 20 Hz (deep bass) to 20,000 Hz (high treble) and over the audible range of 0 dB (the threshold of perception) to 140 dB (the threshold of pain). The ear does not respond equally to different frequencies of the same magnitude, but is more responsive to mid-frequencies than to lower or higher frequencies. To quantify noise in a manner that approximates the response of the human ear, a weighting mechanism is used. This reduces the importance of lower and higher frequencies, in a similar manner to the human ear.

Furthermore, the perception of noise may be determined by a number of other factors, which may not necessarily be acoustic. In general, the impact of noise depends upon its level, the margin by which it exceeds the background level, its character and its variation over a given period of time. In some cases, the time of day and other acoustic features such as tonality or impulsiveness may be important, as may the disposition of the affected individual. Any assessment of noise should give due consideration to all of these factors when assessing the significance of a noise source.

The most widely used weighting mechanism that best corresponds to the response of the human ear is the ‘A’-weighting scale. This is widely used for environmental noise measurement, and the levels are denoted as dB(A) or LAeq, LA90 etc., according to the parameter being measured.

The decibel scale is logarithmic rather than linear, and hence a 3 dB increase in sound level represents a doubling of the sound energy present. Judgement of sound is subjective, but as a general guide a 10 dB(A) increase can be taken to represent a doubling of loudness, whilst an increase in the order of 3 dB(A) is generally regarded as the minimum difference needed to perceive a change under normal listening conditions.

An indication of the range of sound levels commonly found in the environment is given in the following table.

Table A1: Typical Sound Pressure Levels

Sound Pressure Level dB(A)

Location

0 Threshold of hearing

20 - 30 Quiet bedroom at night

30 - 40 Living room during the day

40 - 50 Typical office

50 - 60 Inside a car

60 - 70 Typical high street

70 - 90 Inside factory

100 - 110 Burglar alarm at 1m away

110 - 130 Jet aircraft on take off

140 Threshold of pain



Acoustic Terminology

Table A2: Terminology

Descriptor Explanation

dB (decibel) The scale on which sound pressure level is expressed. It is defined as 20 times the logarithm of the ratio between the root-mean-square pressure of the sound field and a reference pressure (2x10-5Pa).

dB(A) A-weighted decibel. This is a measure of the overall level of sound across the audible spectrum with a frequency weighting (i.e. ‘A’ weighting) to compensate for the varying sensitivity of the human ear to sound at different frequencies.

LAeq, T LAeq is defined as the notional steady sound level which, over a stated period of time (T), would contain the same amount of acoustical energy as the A - weighted fluctuating sound measured over that period.

LAmax

LAmax is the maximum A - weighted sound pressure level recorded over the period stated. LAmax is sometimes used in assessing environmental noise where occasional loud noises occur, which may have little effect on the overall Leq noise level but will still affect the noise environment. Unless described otherwise, it is measured using the 'fast' sound level meter response.

L10 & L90

If a non-steady noise is to be described it is necessary to know both its level and the degree of fluctuation. The Ln indices are used for this purpose, and the term refers to the level exceeded for n% of the time. Hence L10 is the level exceeded for 10% of the time and as such can be regarded as the 'average maximum level'. Similarly, L90 is the ‘average minimum level’ and is often used to describe the background noise. It is common practice to use the L10 index to describe traffic noise.

Free-field Level

A sound field determined at a point away from reflective surfaces other than the ground with no significant contributions due to sound from other reflective surfaces. Generally as measured outside and away from buildings.

Fast A time weighting used in the root mean square section of a sound level meter with a 125millisecond time constant.

Slow A time weighting used in the root mean square section of a sound level meter with a 1000millisecond time constant.



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Figure 1 Proposed Site Layout, Noise Measurement Positions and Batch A



Figure 2 Suggested Acoustic Fence Locations

Documents

NOISE IMPACT ASSESSMENT - Ribble Valley · ‘avoid noise from giving rise to significant adverse impacts on health and quality of life as a result of development; mitigate and reduce