hand car wash & tyre fitting facility: noise impact ... · if the car wash bay is fully...

Kayz Tyres Ltd Langley Place, Crawley, West Sussex

Hand Car Wash & Tyre fitting Facility:

Noise Impact Assessment Report

Report No: 120/Rep 1/Rev 1/Aug 2013

Dr H S Sagoo – Acoustics, Noise & Vibration Consultants PhD, BSc (1

st Hons), CEng, MIOA, MIMechE

FINAL REPORT

REPORT NO: 120/Rep 1/Rev 1/AUG 2013

SUBMITTED TO: KAYZ TYRES LTD

11 CELANDINE CLOSE

BROADFIELD

CRAWLEY RH11 9EB

ATTENTION: MR M I KHAN

OWNER

PREPARED & SUBMITTED BY:

Dr H S SAGOO – Acoustics, Noise & Vibration Consultants

‘Havenwood’

110 Hiltingbury Road

Chandlers Ford

Hampshire SO53 5NT

02380 251239 0772 052 9702

Revision 0 First issue

Revision 1 New revised layout of car wash

Dr H S Sagoo – Acoustics, Noise & Vibration Consultants

Report No: 120/Rep 1/Rev 1 16th August 2013

SUMMARY

A hand car wash and a tyre fitting facility is presently being proposed at the premises at Langley Place in Crawley; this was previously used as a builders merchant / yard and is now vacant. As prerequisite for this change of use, Crawley Borough Council as the local authority highlighted some concern about the possible adverse impact of noise arising from the activities in connection with the new activities and therefore has asked for an assessment of the impact arising from the noise cause by activities upon the local noise sensitive receptors. The owner approached Dr H S Sagoo – an experienced independent Noise and Vibration Consultant – to undertake the noise survey and prepare the requisite noise assessment. The measurement of the background noise levels was previously agreed with the EHO and measured over a period commencing noon on Wednesday, 19th June 2013 until about 16:00 hrs at the site boundary with Poplar Close. Noise levels were also measured in the open green space close to the nearest house in Rushetts Place from 13:00 to 15:00 hrs. The ambient background noise level was found to be 44 dB LA90. Noise of the compressor and the ratchet gun was measured at an operating tyre shop bay elsewhere. Source noise level of 73 dB LAeq was measured over an hour which included the compressor (about 5-7m away), the ratchet gun (about 5m away), and people talking (about 2-4m away). Without any mitigation, if the wheels are changed in the space between the two wooden shed the noise impact will exceed the measured background noise and will not meet the LA criteria. If this open space is covered with marine plywood and felt roofing laid on 200mm joists and blocked on the sides and properly sealed at the edges as shown on the architect’s drawings, the noise impact would be markedly reduced and would then meet the LA acceptance criteria. If tyre changing is carried out within the brick building then noise impact is not considered to be an issue. The noise of car washing was measured at a similar hand car wash facility in Crawley where the pumps were installed in an enclosure within a building and two hoses were available outside and each was fitted with a water jet lance for car washing. A noise level of 75.1 dB LAeq was recorded for two car washes and the use of a vacuum cleaner over a period of about 20 minutes. This is considered to be a representative sample. Without any mitigation, the noise impact at the nearest house in Poplar Close is predicted to exceed the measured background noise by about 13 dB. If the car wash bay is fully enclosed as shown by the architect’s drawings with 6mm Perspex material with a sound reduction of Rw 27 dB, then the predicted noise impact would be reduced and would then meet the LA acceptance criteria. It would be prudent to install a 2m tall solid barrier, such as a timber fence, along the steel railing boundary fence and this should be sealed along the wall of the brick building. This barrier would help to screen some activities on the car wash site from the houses in Poplar Close. The water pumps should be installed in a wooden enclosure within the car wash bay and acoustically lined cover.

Adoption of the mitigation measures as recommended above will ensure that noise arising from the tyre fitting and hand car wash activities will meet the Local Authority’s acceptance criteria and hence the facility should be granted planning permission.


Report No: 120/Rep 1/Rev 1 1 16th August 2013

CONTENTS 1 INTRODUCTION 2 DESCRIPTION OF THE SITE

3 DEVELOPMENT PROPOSAL 4 NOISE CRITERIA

5 NOISE MEASUREMENTS 6 INSTRUMENTATION 7 NOISE MEASUREMENT RESULTS 8 ASSESSMENT OF THE NOISE IMPACT AND MITIGATION 9 MITIGATION MEASURES

10 CONCLUSIONS Table 1 BS 4142 Assessment Criteria Table 2 Ambient and Source Noise Measurement Table 3 Activities at measurement location close to Rushetts Place Table 4 Source Noise Levels Table 5 BS4142 Assessment for ratchet gun Table 6 Specification of Sound Reduction Values Table 7 BS4142 Assessment for car wash activities Table 8 BS4142 Assessment with a Noise Barrier Figure 1 Map of Crawley and location of site at Langley Place Figure 2 Background noise time histories Figure 3 Measurement time history of ratchet gun Figure 4 Noise levels during car washing and vacuuming Figure 5 Location of car wash facility APPENDIX 1: Acoustic Terminology APPENDIX 2: Site Photographs APPENDIX 3: Noise measurement results



1. INTRODUCTION

A hand car wash and a tyre fitting facility is presently being proposed at the premises at Langley Place in Crawley; this was previously used as a builders merchant / yard and is now vacant. As prerequisite for this change of use, Crawley Borough Council as the local authority highlighted some concern about the possible adverse impact of noise arising from the activities in connection with the new activities and therefore has asked for an assessment of the impact arising from the noise cause by activities upon the local noise sensitive receptors. The owner approached Dr H S Sagoo – an experienced independent Noise and Vibration Consultant – to undertake the noise survey and prepare the requisite noise assessment. The purpose of this report is to describe the site, the nearest residential areas, brief details of the proposal and outline the assessment methodology including the findings of the noise survey, assessment of the noise impact in accordance with the appropriate national guidance, and finally, recommend noise mitigation measures as necessary.

2. DESCRIPTION OF THE SITE

Crawley is located about 4km south of Gatwick airport. Langley Green is located about 1500m north of Crawley town centre and about 2500m south of the airport. See map in Figure 1. There is a shopping arcade with flats above in the area and the access to the shops and the flats is off one side of Langley Place and there are a number of a/c units clearly visible from this road; on the other is the proposed car wash site. A lot of car movements were seen along Langley Place. To the northeast, the proposed site is flanked by Poplar Close, a cul-de-sac, which has residential properties on the opposite side about 15m from the site boundary wall. There were many car movements on Poplar Close. To the northwest of the proposed site is an open green space with public footpaths and access to the local shops. The nearest noise sensitive receptors are considered to be the houses in Poplar Close and in Rushetts Place across the green space.

3. DEVELOPMENT PROPOSAL

The premises has a large open yard accessed by large iron gates off Langley Place which then leads to a two storey brick building and two wooden sheds. It is understood that the two wooden sheds are proposed to be used for storage of tyres. Vehicles requiring change of tyres would be driven into the brick building where wheels will be removed, old tyres will be taken off and replaced with new tyres, wheel would then be balanced before finally being fitted to the vehicle. The machines for tyre removal and refitting together with all ancillary equipment and tools including a quiet mode air compressor are all proposed to be housed within the existing brick building. The car washing facility is proposed to be undertaken in a separate large bay alongside the steel railing site boundary fence and straight ahead from the entrance. Two sets of



jet wash lances are proposed and the pumps would be housed in an enclosure, possibly of brick construction, within the wash bay. This enclosure would ensure that noise of the pumps is minimised and also provide security against theft. The brick building would appear to be constructed of traditional plastered concrete blocks on the inside and brick on the outside. The wooden sheds appear to be constructed of plywood for walls and plywood and flat roofing felt laid on 200mm joists. The architect’s drawing, 094-006B, shows the space between the two sheds, the alley between a shed and the brick building, the space in front of the brick building, would be covered. The car wash bay would also be covered with plastic roof panelling with the sides made of plastic cladding to match roof panelling. Proposed working The proposed opening hours are understood to be 08:00 to 18:00 hrs Monday to Friday, 08:00 to 16:00 hrs on Saturday and no working on Sunday. The following are proposed to be installed in the brick building:

various storage racks for tools;

two tyre changers manufactured by Corghi;

one tyre balancing machine manufactured by Corghi;

one quiet mode air compressor;

2no. Snap-On battery operated impact guns;

four trolley hydraulic jacks car wash equipment;

one Karcher jet wash machine with boiler

one Karcher jet wash machine without boiler

a pair of jet water lances for washing.

4. NOISE CRITERIA

Assessment criteria British Standard 41421 gives guidance on measurement and assessment of the impact of noise due to industrial installations and plant on nearby residents and to determine whether this is likely to give rise to complaints. In essence, the noise level and the character of noise caused by the specific source i.e. tyre removal and car wash equipment, called the rating level, is measured and rated against the measured ambient background level LA90 during the opening hours of the shop. The greater this difference the greater is the likelihood of complaints, as given in Table 1. This standard states a reference time period of 1 hr during the day and 5 minute during the night for specific noise and 1 hr for background noise at all times.

1 British Standard 4142:1997 ‘Method for rating industrial noise affecting mixed residential and

industrial areas’.



Difference in dB Comment

+10 dB or more Indicates that complaints are likely

+5 dB Is of marginal significance

Rating level more than 10 dB below the measured background level

This is a positive indication that complaints are unlikely

Table 1 BS 4142 Assessment Criteria Acceptance criteria The local authority2 was contacted to check their acceptance criterion with respect to BS 4142 assessment and this was for the rating noise level to be 10 dB below the measured background noise level, LA90, in the period of operation.

5. NOISE MEASUREMENTS

Background noise measurements The measurement of the background noise levels was previously agreed with the EHO and measured over a period commencing approximately noon on Wednesday, 19th June 2013 until about 16:00 hrs at the site boundary with Poplar Close, see Photo 1. Noise levels were also measured in the open green space close to the nearest house in Rushetts Place from about 13:00 to 15:00 hrs, see Photo 2. The objective was to understand the typical ambient noise climate close to the nearest residence that is likely to be most impacted by noise. Measurements include the equivalent continuous noise level LAeq, the background noise level LA90, the maximum level LAmax and LA10 together with third octave frequency spectra. Explanation of acoustical terminology is given in Appendix 1. All noise measurements are considered to be free-field when considering the main noise source in the area and the microphone was mounted so that it was clear of local boundary fences/walls on a secure tri-pod and measurements were conducted in accordance with the guidelines given in BS4142. The weather was dry and sunny and there was a light north-easterly breeze of 0.5 m/s with gusts up to 1.0 m/s.

Source noise measurements The noise generated by operations such as the impact ratchet gun, the air compressor, was measured at a site elsewhere in a building that was fairly reverberant and the sound measurements were taken about 4-5 m distance from each activity and thus this represented typical noise levels. The noise level caused by water jets during car wash was measured at another car wash facility nearby. At this particular site, it was seen that the pumps were installed inside a building and boxed in a wooden enclosure.

2 Conversation with Mr R Burns, EHO at Crawley Borough Council.



6. INSTRUMENTATION Noise measurements were taken using two 01dB Solo Type 1 integrating sound level meters (serial no. 10485 and 60354) each fitted with a ½ inch microphone. These were calibrated using a 01dB Calibrator (serial no. 130366) in accordance with the manufacturer’s instructions before and after the measurements, and no drift in calibration level was observed and were set-up to record the one third octave frequency spectra of the ambient noise.

7. NOISE MEASUREMENT RESULTS

The results of the ambient noise levels are summarised in Table 2 and the time history of 10-second averages is given in Figure 2, and the observations are noted in Table 3. The source noise measurements including the compressor, the ratchet gun and the car wash are given in Table 4 and the time history is given in Figure 3. Detailed results are given in Appendix 3.

Site boundary with Poplar Close

Rushetts Place/ green space

Period start LAeq LAmax LA90 LA10 LAeq LAmax LA90 LA10

19/06/2013 12:00 55.1 80.4 43.8 54.8

19/06/2013 13:00 63.4 86.6 45.1 65.1 67.6 88.7 45.2 68.2

19/06/2013 14:00 59.6 74.1 44.4 63.5 73.5 90.1 44.6 78 19/06/2013 15:00 54.3 83.4 44 53.9

Noise levels are in dB

Table 2 Ambient and source noise measurements

Start time End time Activity and comments

13:04:16 Items dropped by some builders 13:04:46 Person on bicycle 13:05:16 Council grass mowers start engines and drive away; constant noise

of generators ended at 13:08:26 13:08:41 Aircraft; people walking past 13:11:32 Person on bicycle 13:14:50 Another person on bike, aircraft 13:17:20 Grass trimmer 13:20:12 Aircraft 13:36:32 Person on bike 13:38:24 13:42 Grass mowers getting closer and then gone away 13:47:20 13:50:52 14:03 Council grass mowers coming and going every two minutes 13:54:22 13:54:26 Car alarm 14:05:00 Lady started talking 14:20:11 Air blower 14:30:20 Aircraft 14:42:30 Aircraft, bird chirp


Table 3 Activities at measurement location close to Rushetts Place



Source noise levels – tyre fitting It was noted that although the tyre fitting works can include a number of noisy activities or operations, these activities are usually not frequent and, when they do occur, are generally of short duration, usually less than a minute, see Figure 3, and hence their effect on the noise level averaged over a period of 1 hour (the assessment period in BS4142 for daytime activities) is usually not significant as these peak levels are averaged out. Night-time assessment does not apply as there is no proposed night-time opening. The ratchet gun proposed to be used is battery powered and this is not as noisy compared to pneumatic operated. The tyre removal and the wheel balancing machines are proposed to be electric and these are generally quiet and it is understood that these are to be installed in the brick building in which case the noise from these machines will hardly be audible outside. The air compressor will only be used to inflate the tyre to the desired pressure after fitting. Usually, the air compressor operates automatically to build up pressure to a set level: it operates for about 6 minutes at a time and its on-off frequency depends on how busy the tyre fitting may be.

Source noise LAeq LAmax LA90 LA10

Compressor and ratchet gun in a workshop 8/02/2013 11:00 – 12:00 73 85.5 56.9 78.5

Jet car wash at 2.5m 19/06/2013 13:40 – 13:58 hrs 75.1 85.6 60.9 79.4


Table 4 Source noise levels

8. ASSESSMENT OF THE NOISE IMPACT AND MITIGATION

The assessment considers the site at present, i.e. uncovered without any additional mitigation, to determine the adverse noise impact and the findings will then be used to select appropriate mitigation. Ambient background noise levels The ambient noise levels measured close to Poplar Close and Rushetts Place, shown as hourly averages in Table 2 and variation of 10-second averages in Figure 2, are typical of a location close to a busy main road with significant traffic. The ambient background noise level was found to be 44 dB LA90.

1) Source noise levels – tyre fitting Noise of the compressor and the ratchet gun was measured at an operating tyre shop bay elsewhere. Source noise level of 73 dB LAeq was measured over an hour which included the compressor (about 5-7m away), the ratchet gun (about 5m away), and people talking (about 2-4m away). The measurement was free-field and at a height of



about 1.2 m above ground. The time history of noise measurements close to a ratchet gun is given in Figure 3. It is understood that the vehicle would be driven into the brick building for the change of tyres in which case the noise impact to the neighbourhood is considered to be nil. However, for a worst case scenario the following assessment applies if the wheel removal and fitting using a ratchet gun is carried out in the space between the two wooden sheds. The shed structure, about 2.5m high, will screen the houses in Poplar Close and the boundary wall, about 1.8m tall, will screen the houses in Rushetts Place. The Makeawa method is used to determine the barrier correction and this is based on calculating the path difference between the direct line and the line taken to skim the barrier or wall. The assessment is as follows and includes a 5 dB character correction as per BS4142 for the rating noise level.

Receptor

1st floor

Window

Source noise level dB LAeq at

5m

Compressor /ratchet gun

Dist to house/

dist attenu-ation.

Barrier corr

Specific Noise Level

dB

Rating Noise Level

dB

Lowest measured

noise level dB

LA90

Excess or

otherwise dB

Poplar Close

73.0 29m/ -15.3

-12.7 45.0 50.0 44.0 + 6

Rushetts Place

73.0 35m/ -16.9

-10.3 45.8 50.8 44.0 + 6.8

Table 5 BS4142 Assessment for ratchet gun

Assessment The above shows that the rating noise level caused by the use of the ratchet gun would be approximately 6 dB above the lowest measured ambient LA90 level for daytime. This assessment represents the worst case scenario because it is based on the combined noise of the compressor and the ratchet gun. The impact may be slightly greater towards Poplar Close because of the open/uncovered alley next to the wooden shed. In accordance with the guidelines in BS4142, the rating noise level is of ‘marginal significance’ and the rating level does not meet the LA requirement. A noise reduction of about 17 dB is required to meet the LA requirement. Mitigation It is suggested that the space between the two wooden sheds is covered and the space above the boundary wall is blocked and all edges should be properly sealed. Similarly, the open alley towards Poplar Close should be covered and the end blocked. This is shown on the architect’s drawings. As a result, the location for wheel changing will be completely covered and thus screened from the houses in Poplar Close and those surrounding the green open space.



The requirement is for some material to provide sound reduction of a minimum 17 dB. A 6mm thick sheet of Perspex/Plexiglass/Acrylic3 has a sound reduction index of 29 to 31 dB from literature, and 18mm marine plywood (and flat roofing felt over 200mm deep joists for the roof) has sound insulation of more than 27 dB4 and data for this and an alternative option is given in Table 6. This sound reduction value is a magnitude more than the barrier correction given in Table 5 above. Consequently, the noise transmitted to the nearby houses would be close to 20 dB below the measured background noise level; hence meet the LA requirement.

Sound reduction index values dB

Octave frequency Hz 125 250 500 1k 2k 4k Rw

Sample construction:

18mm plywood – surface weight of 10 kg/sqm

24 22 27 28 25 27 27

18g galvanised sheet steel – surface weight of 10 kg/sqm

13 20 24 29 33 39 29

Perspex/Plexiglass – flat frequency 29

Table 6 Specification of sound reduction values 2) Source noise levels – Compressor noise

Assuming the noise of a typical compressor is 73 dB LAeq and that the compressor will be located within the brick building, which is likely to have a combined sound reduction index of approximately 40 dB (based on Rw 54 dB for a brick cavity wall and Rw 33 dB for the small double glazed windows), it is considered that the noise transmitted to the nearest houses in Poplar Close would be more than 10 dB below the measured background noise level of 44 dB, and hence meet the LA requirement.

3) Source noise levels – car washing The car wash bay is proposed as shown in Figure 5; it is located straight ahead from the entrance gate. The noise of car washing was measured at a similar hand car wash facility in Crawley where the pumps were installed in an enclosure within a building and two hoses were available outside and each was fitted with a water jet lance. Thus the noise that is generated externally is that by the water jets. The car wash cycle includes various actions; a rapid soaking all over the car body using the water jets, application of car shampoo by large mops for the body and small brushes for the tyres, alloy wheels and difficult areas, final soaking and cleaning with water jets, the car is then moved forward just enough to turn the wheels by half a turn so that the dirty section is now at the top and easier to clean with water jets. The car body is then dried, the inside is vacuumed and polished inside and out. A similar proposition is proposed at Langley Place. The noise level was measured about 2.5m to one side of the car being washed and a pair of lances was being used. Noise levels varied in magnitude and mostly in frequency depending upon where the jet was pointed; i.e. the plane surface of the body

3 data sheet from ePlastics.com

4 Building Bulletin 51, 1976.



or the sharps edges of the alloy wheels, the wheel arches and plastic grill, etc. Most of the activities involve no noise at all. The measurement also includes noise inside a bay during vacuuming; time history is shown in Figure 4. A noise level of 75.1 dB LAeq was recorded for two car washes and the use of a vacuum cleaner over a period of about 20 minutes. This is considered to be a representative sample and perhaps a worst case sample as the activity was continuous with people talking when the car was being dried and polished whereas in practice over a typical hour there are likely to be pauses between car washes. For noise predictions, the centre of the car is assumed to be about 5m from the steel railing fence when it is being washed and to determine what mitigation may be required initially no mitigation is assumed in the noise assessment. Some houses in Poplar Close will be screened by the brick building and others will not be screened; the steel railing fence is not considered an acoustic barrier, hence these houses are the worst affected. Houses in Rushetts Place will be screened by the 2.6m high wall and wooden shed. The predicted noise levels and the assessment are given in the table below.

Receptor

Source noise level dB LAeq at

2.5m

Dist to house/

dist attenu-ation.

Barrier corr*

Specific Noise Level

dB

Rating Noise Level

dB

Lowest measured

noise level dB

LA90

Excess or

otherwise dB

1st floor

Window

Car wash water jet

Poplar Close

75.1 34m/ -22.7

0 52.4 57.4 44.0 + 13.4

Rushetts Place

75.1 54m/ -26.7

-8.7 39.7 44.7 44.0 + 0.7

* calculated using Makaewa method

Table 7 BS4142 Assessment for car wash activities

This assessment without mitigation shows that the worst case rating noise level at Rushetts Place is equal to the measured background whereas at Poplar Close the level is about 13 dB above the measured background noise level. Subsequently, some mitigation is necessary to reduce the noise impact by almost 23 dB for houses in Poplar Close and about 10 dB for houses in Rushetts Place to meet the LA requirements. From experience, this task is beyond a simple barrier and an enclosure is necessary. Mitigation It is proposed that the car wash bay is in a full enclosure except for the open entrance. As mentioned above, 6mm Perspex sheet, 18mm plywood or 18g galvanised sheet steel has sound insulation Rw of 27-29 dB. It is considered that if the enclosure is constructed from these material or better, the noise impact at all of the surrounding houses would meet the LA criteria.

9. MITIGATION MEASURES

Following our discussions with the architect and the client, it is recommended that the existing open uncovered space between the two wooden sheds and the alley between



the shed and the brick building be covered with marine plywood with flat roofing felt laid on 200mm joists. Also, the sides are made of plywood-100mm stud with mineral wool-chipboard partition, and fully sealed at the edges. The car wash bay should be fully enclosed as shown in the architect’s drawings with 6mm Perspex material of at least Rw 27 dB and acoustically sealed at the edges. It would be prudent to install a 2m tall solid barrier, such as a timber fence, along the steel railing boundary fence and this should be sealed along the wall of the brick building. This barrier would help to screen some activities on the car wash site from the houses in Poplar Close. The Karcher pumps should be installed in a wooden enclosure within the car wash bay with acoustically lined cover to allow access for maintenance.

10. CONCLUSIONS

The measurement of the background noise levels was agreed with the EHO and measured over a period commencing approximately noon on Wednesday, 19th June 2013 until about 16:00 hrs at the site boundary with Poplar Close. Noise levels were also measured in the open green space close to the nearest house in Rushetts Place from about 13:00 to 15:00 hrs. The ambient background noise level was found to be 44 dB LA90. Noise of the compressor and the ratchet gun was measured at an operating tyre shop bay elsewhere. Source noise level of 73 dB LAeq was measured over an hour which included the compressor (about 5-7m away), the ratchet gun (about 5m away), and people talking (about 2-4m away). Without any mitigation, if the wheels are changed in the space between the two wooden shed the noise impact will exceed the measured background noise and will not meet the LA criteria. If this open space is covered with marine plywood and felt roofing laid on 200mm joists and blocked on the sides and properly sealed at the edges as shown on the architect’s drawings, the noise impact would be markedly reduced and would then meet the LA acceptance criteria. If tyre changing is carried out within the brick building then noise impact is not considered to be an issue. The noise of car washing was measured at a similar hand car wash facility in Crawley where the pumps were installed in an enclosure within a building and two hoses were available outside and each was fitted with a water jet lance for car washing. A noise level of 75.1 dB LAeq was recorded for two car washes and the use of a vacuum cleaner over a period of about 20 minutes. This is considered to be a representative sample. Without any mitigation, the noise impact at the nearest house in Poplar Close is predicted to exceed the measured background noise by about 13 dB. If the car wash bay is fully enclosed as shown by the architect’s drawings with 6mm Perspex material with a sound reduction of Rw 27 dB, then the predicted noise impact would be reduced and would then meet the LA acceptance criteria. It would be prudent to install a 2m tall solid barrier, such as a timber fence, along the steel railing boundary fence and this should be sealed along the wall of the brick building. This barrier would help to screen some activities on the car wash site from the houses in Poplar Close. The water pumps should be installed in a wooden enclosure within the car wash bay and acoustically lined cover.



FIGURE 1 Map of Crawley and location of site at Langley Place

Proposed tyre and car wash

facility

Location 1 – boundary with Poplar Close

Location 2 –close to

Rushetts Place



Site boundary with Poplar Close

Close to house in Rushetts Place

FIGURE 2 Background noise time histories

#4 Leq 1s A dB dBWED 19/06/13 12h09m04 WED 19/06/13 15h56m14

30

35

40

45

50

55

60

65

70

75

80

85

90

12h 13h 14h 15h 16h

#24 Leq 1s A dB dBWED 19/06/13 13h01m15 61.1 WED 19/06/13 14h51m33

30

35

40

45

50

55

60

65

70

75

80

85

90

12h 13h 14h 15h 16h



These measurements were made inside a workshop at One Stop Tyre Shop in Birmingham on 8

th February 2013.

FIGURE 3 Measurement time history of ratchet gun

Solo 060354 Leq 1s A dB dBFRI 08/02/13 10h59m26 56.6 FRI 08/02/13 11h57m26 58.3

50

55

60

65

70

75

80

85

90

11h00 11h05 11h10 11h15 11h20 11h25 11h30 11h35 11h40 11h45 11h50 11h55

Solo 060354 Leq 1s A dB dBFRI 08/02/13 11h20m00 80.9 FRI 08/02/13 11h21m08 57.3

50

55

60

65

70

75

80

85

90

20m00 20m10 20m20 20m30 20m40 20m50 21m00

5 wheel nuts tightened by impact gun – in about 15 seconds

Compressor on – 85 dB at 2m

Impact gun used on forecourt

Impact gun to tighten nuts

2 post ramp raised/lowered



FIGURE 4 Noise levels during car washing and vacuuming

FIGURE 5 Location of car wash facility

Solo 060354 Leq 1s A dB dBWED 19/06/13 13h40m13 57.5 WED 19/06/13 13h58m58 62.9

50

55

60

65

70

75

80

85

90

13h42 13h44 13h46 13h48 13h50 13h52 13h54 13h56 13h58

Car 2 washing Car 1 washing Car vacuum and people

talking



Appendix 1 Acoustic Terminology



Appendix 1 Acoustic Terminology

Perception of sound. Sound is a rapid fluctuation in air pressure. The human ear can

hear sensations of sound when the fluctuations occur between 20 times a second and

20,000 times a second. This is called the frequency of the sound and is measured in

Hertz (Hz). The loudness of the sound depends on the amplitude of fluctuation in the air

pressure. The ear has an approximately logarithmic response to the loudness of sound:

for example, every doubling or halving in sound pressure gives an apparently equal

step increase or decrease. In measuring environmental noise, sound pressure levels

are therefore usually quoted in terms of a logarithmic unit known as a decibel (dB).

Typically, the quietest sound that can be heard (the threshold of hearing) is 0 dB and

the sound becomes painful at 120 dB. The sensitivity and frequency range of the ear

varies somewhat from person to person and deteriorates with age and exposure to loud

sounds

“A” Weighting. The human ear is not equally sensitive to sounds of different

frequencies (i.e. pitch): it tends to be more sensitive in the frequency range of the

human voice than at higher or lower frequencies. When measuring sound,

compensation for these effects can be made by applying a frequency weighting, usually

the so-called “A” weighting, although other weightings are sometimes used for special

purposes. To signify that the “A” weighting has been applied, the symbol of dB(A) is

often used. However, current practice tends to prefer the weighting letter to be included

in the name of the measurement index, e.g. dB(A) Leq and dB LAeq both refer to the “A”

weighting equivalent continuous sound level in decibels.

LAeqT

is a unit that also takes into account fluctuations in sound pressure levels. This

unit takes into account both steady and impulsive noises and is defined as the steady,

continuous sound pressure level which contains the same energy as the actual,

fluctuating sound pressure level. It is necessary to state the time period over which the

sound is measured, e.g. LAeq,(12-hour)

, typical in the case of daytime working and 5-minute

for night-time.

LA90 is the level of A-weighted sound exceeded for 90% of the measurement period. It

is generally used as a measure of the background noise in environment noise

standards.



Appendix 2 Site Photographs



Photo 1 Noise measurement location 1 at site boundary with Poplar Close

Photo 2 Noise measurement location 2 close to house in Rushetts Place



Photo 3 View of proposed site from measurement location 2

Photo 4 View from car wash area, steel railing fence and houses in Poplar Close



Appendix 3 Noise measurement results

Table A3.1 Ambient noise measurement results in hourly averages Table A3.2 Source noise levels



Start LAeq LAmax LA90 LA10

Octave Band Frequency Hz Time

16 31.5 63 125 250 500 1k 2k 4k 8k 16k

Location 1 – boundary with Poplar Close 12:00 55.1 80.4 43.8 54.8

59.3 62.9 63.5 57.9 53.6 51.5 49.1 47.9 42.7 38.2 27.4

13:00 63.4 86.6 45.1 65.1

58.6 59.5 63.8 65.0 60.1 58.8 56.2 54.5 55.0 57.7 48.0 14:00 59.6 74.1 44.4 63.5

58.3 59.8 66.3 67.6 60.8 54.4 51.3 51.2 48.3 42.6 27.8

15:00 54.3 83.4 44 53.9

59.1 60.7 58.1 55.7 52.2 49.8 47.3 48.4 44.0 39.7 34.0

Location 2 – close to house in Rushetts Place 13:00 67.6 88.7 45.2 68.2

57.8 58.5 70.2 73.7 66.7 62.0 60.0 58.5 60.0 59.0 49.2

14:00 73.5 90.1 44.6 78

57.0 63.8 78.8 81.6 73.9 69.1 65.4 64.9 62.7 56.9 45.6

All noise levels are in dB

Table A3.1 Ambient noise measurement results in hourly averages



Octave Band Frequency Hz

Start and End time LAeq LAmax LA90 LA10

16 31.5 63 125 250 500 1k 2k 4k 8k 16k

8th Feb 2013

Combined noise ratchet gun, compressor and people Inside bay 10:59:26 11:57:27 73 85.5 56.9 78.5

67.0 68.7 71.1 64.5 64.6 65.7 64.8 68.8 65.0 60.2 54.9

Ratchet gun Inside bay 11:20:38 11:20:58 75.4 81.9 60.7 80.2

59.9 61.5 66.6 60.0 60.6 63.7 66.9 70.9 69.1 64.9 55.6

19th June 2013

Noise close to car wash facility

13:40:13 13:58:59 75.1 85.6 60.9 79.4

83.8 76.2 74.0 68.0 69.8 73.4 68.1 67.2 66.6 64.4 58.8

All noise levels are in dB

Table A3.2 Source noise levels

hand car wash & tyre fitting facility: noise impact ... · if the car wash bay is fully...

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