NOISE ASSESSMENT HASLINGDEN SPORTS CENTRE, … · BB4 7SN Dan Clayton // BSc (Hons) Acoustics, AMIOA // [email protected] Summary A noise survey has been undertaken at the

REPORT NO. 10036

CLIENT: ROSSENDALE BOROUGH COUNCIL

DATE OF ISSUE : 29th September 2010

NOISE ASSESSMENT

for the sites at

HASLINGDEN SPORTS CENTRE, HELMSHORE ROAD, ROSSENDALE, BB4 4DN

AND

MARL PITTS SWIMMING POOL, NEWCHURCH ROAD, ROSSENDALE, BB4 7SN

Dan Clayton // BSc (Hons) Acoustics, AMIOA // [email protected]

Summary

A noise survey has been undertaken at the site of Haslingden Sports Centre, Helmshore Road, Rossendale,

BB4 4DN and Marl Pitts Swimming Pool, Newchurch Road, Rossendale, BB4 7SN with the aim to assess the

potential noise impact from proposed alterations to local sensitive receptors near the existing sites. Noise

measurements of the existing noise climate have been taken at the nearest residential dwellings and the noise levels from proposed operations have been predicted using measured and calculated data. It is envisaged that

noise due to the proposed alterations at both sites should be imperceptible at the nearest residences. The

following recommendations have been made to ensure that the local amenity is preserved at both sites in

regards to noise. The proposed ancillary equipment at Haslingden sports centre should have a maximum external noise level of 42dB LAeq,T @3m. The ancillary equipment at Marl Pitts Swimming Pool should be

mounted on the façade facing away from the nearest residences and have a maximum noise level of 68dB

LAeq,T @3m. The noise from the plant should also be broad band and not tonal in frequency. It is

recommended that there is no noise egress from the operations within the buildings such as swimming pools, fitness suites and sports halls. All access doors should be sealed well with this in mind. It is also envisaged

that increased noise on the main roads from increased traffic flow at the sites will be negligible.

0 INTRODUCTION

Braiden Acoustics has been commissioned by

Rossendale Borough Council to undertake a

Noise Assessment at the sites of Haslingden

Sports Centre, Helmshore Road, Rossendale,

BB4 4DN and Marl Pitts Swimming Pool, New-

church Road, Rossendale, BB4 7SN with the aim

to support an outline planning application for the

extension and increased use of each develop-

ment.

This report describes the approach, methodology

and conclusions of the noise assessment.

Noise Assessment Haslingden Sports Centre, Helmshore Road, Rossendale, BB4 4DN and Marl Pitts Swimming Pool, Newchurch Road, Rossendale, BB4 7SN

Dan Clayton - 2 - Braiden Acoustics

[email protected] www.braidenacoustics.co.uk

1 DESCRIPTION OF SITES

1.1 Haslingden Sports Centre

A plan view of Haslingden Sports Centre and the

surrounding area is shown in Figure 1.

As shown in Figure 1 the external areas of the

sports centre are 3 open-air tennis courts, a 5-A-

Side astro-turf football pitch (again uncovered)

and car parking adjacent to Helmshore Road.

The surrounding area is predominantly residen-

tial; however, there is a public house with exter-

nal smoking area in close proximity to the sports

centre.

Figure 1

Existing Haslingden Sports Centre layout and surround-

ing uses

1.2 Marl Pitts Swimming Pool

The Marl Pitts swimming pool is also in a pre-

dominantly residential area as shown in Figure 2.

The only external land associated with it is a car

park directly to the south. However, there are

other sports facilities to the east of the site such

as an athletics track and rugby club although

these are not directly linked to the swimming

pool. The site is serviced by Newchurch Road to

the south.

Figure 2

Existing Marl Pitts Swimming Pool layout and surround-

ing uses

1.3 Current uses

The current uses for each site are given below.

The current opening times are given in Appendix

A3.

1.3.1 Haslingden Sports Centre

The sports centre currently has indoor and out-

door facilities. The indoor facilities are a large

multi-use sports hall, a fitness suite, two squash

courts and a number of small changing rooms.

The outdoor facilities are a 5-A-Side football pitch

and 3 tennis courts.

From admissions data from 2006-2010 supplied

by Rossendale Leisure Trust Ltd. the average

current yearly head count for the sports centre is

150,665 admissions.

1.3.2 Marl Pitts Swimming Pool

The swimming pool building contains a swimming

pool and changing rooms. The surrounding

sports uses are not associated with the swim-

ming pool.

From admissions data from 2006-2010 supplied

by Rossendale Leisure Trust Ltd. the average

current yearly head count for the swimming pool

is 127,609 admissions.

1.4 Proposed uses

Proposals are being made to alter the existing

use of each site. Below are descriptions of the

proposed alterations. The proposed opening

times are given in Appendix A3.


It is estimated that there will be an increase of

100,000 admissions after the proposed altera-

tions. It is proposed that the sports centre will

have a swimming pool over two storeys and vari-

ous changing areas on the ground floor. On the

first floor there will be 4 Spa rooms, a conference

room, three offices and a swimming pool viewing

area. The car parking areas will be also ex-

tended. Diagrams of the proposed alterations

are given in Appendix A2.1.


It is estimated that there will be an increase of

100,000 admissions after the proposed altera-

tions. There will be two fitness rooms situated on

the first floor level and additional changing facili-

ties on the ground floor level. It is also proposed

that 5 no. 5-A-Side football pitches will be sited to

the north of the swimming pool. The car parking




areas will also be extended. Diagrams of the

proposed alterations are given in A2.2.

1.5 Existing / Predicted traffic flow data

After analysis of the existing and proposed traffic

flow data at each site have been provided.

These are shown in Figure 3. These data are

predicted for the busiest period which is 1900hrs

to 2200hrs.

Arrivals Departures Total

Haslingden

Sports

Centre

Existing 54 36 90

Proposed 57 52 109

Diff 3 (5.6%

increase)

16 (44%)

increase

19 (22%

increase)

Marl Pitts

Swimming

Pool

Existing 25 18 43

Proposed 44 32 76

Diff 19 (76%

increase)

14 (78%

increase)

33 (76%

increase)

Figure 3

Traffic flow data

2 MEASUREMENT DETAILS

In order to determine the potential effects from

the proposed operations, noise monitoring was

conducted of the existing noise levels1 at the

nearest receptors at each site and also due to

various operations at each.

2.1 Measuring equipment

The test equipment used was calibrated before

and after measurements, with negligible deviation

(<0.05dB).

A summary of the measuring equipment is given

in Appendix A1.

2.2 Monitoring details

2.2.1 Monitoring times

Noise monitoring was conducted on 23rd Sep-

tember 2010 at various locations throughout both

sites. Noise levels were measured between

1900 and 2230hrs (closing time for both sites is

1 Glossary of terms is given in Appendix A4

2200hrs) as this was deemed a more sensitive

time period when residents are in their homes

and background noise levels are relatively low for

daytime.

Spot noise measurements were taken around

each site with and without each premises operat-

ing.

Weather conditions were damp and overcast with

no wind and a temperature of 150C.

2.2.2 Monitoring locations

All noise monitoring was conducted at 1.2-1.5 m

above local ground and in a free field location as

to reduce any influence from nearby façades.


Figure 4

Haslingden monitoring locations

At Haslingden Sports Centre noise monitoring

was conducted at seven locations. Noise moni-

toring of the current noise levels due to opera-

tions was conducted. Background noise meas-

urements were also conducted at Monitoring Lo-

cation 7 (M7) and M6 which was the closest point

to the nearest residences with no influence from

current operations at the sports centre. The

monitored noise levels will be thought indicative

of the noise levels at the corresponding nearest

residences.





Figure 5

Marl Pitts monitoring locations

Noise monitoring was conducted at two locations

in close proximity to the nearest residential dwell-

ings.

2.3 Monitoring results


2.3.1.1 Background noise levels

ML2 Description

Time

period

(hh:mm)

LA90,T

(dB)

LAeq,T

(dB)

6

Noise from distant road

traffic with no noise from

Sports Centre

21:42 –

21:52 42.9 47.7

4

Noise from distant road

traffic with no noise from

Sports Centre

21:54 –

21:59 40.4 43.4

5

Road traffic noise from

Helmshore Road (5 cars in

measurement)

22:07 –

22:08 52.2 53.5

Figure 6 Background noise levels at Haslingden Sports Centre

2 ML = Monitoring Location

2.3.1.2 Noise levels from operations

ML Event

Time

period

(hh:mm)

LA90,T

(dB)

LAeq,T

(dB)

2 Noise breakout from indoor

football in sports hall

20:45 –

20:49 44.0 49.7

1

@30m from football pitch

(5-A-Side full flow football

match)

20:50 –

21:02 47.9 53.3

4 Patrons leaving sport centre 21:05 –

21:17 40.1 43.7

3 Distant traffic noise and car

leaving site @30m

21:29 –

21:30 40.7 42.0

5 Two cars leaving car park

@10m

22:06 –

22:06 49.4 54.1

Figure 7

Noise from operations at Haslingden Sports Centre


2.3.2.1 Background noise levels

ML Description

Time

period

(hh:mm)

LA90,T

(dB)

LAeq,T

(dB)

1

Noise from road traffic

AC units still in

operation (5 cars per

minute)

22:22 –

22:27 35.7 41.4

2

Noise from road traffic.

AC units still in

operation (5 cars per

minute)

22:28 –

22:27 34.8 43.9

Figure 8

Background noise levels at Marl Pitts Swimming Pool

2.3.2.2 Noise levels from operations

ML Description

Time

period

(hh:mm)

LA90,T

(dB)

LAeq,T

(dB)

1

Swimming pool aerobics

with noise from music

and trainer and AC units

19:09 –

19:19 44.0 48.2

2 5 car movements on car

park and 5 air horn blasts

19:23 –

19:30 42.4 49.1

2

4 car movements on car

park and 1 air horn.

Noise from returning

cross country runners

19:59 –

20:06 42.2 47.6

1 Noise from car

movements and AC units

20:12 –

20:22 39.0 44.2

Figure 9

Noise from operations at Marl Pitts Swimming Pool




3 DETAILS OF ASSESSMENT

The potential direct and indirect changes in noise

level from proposed alterations have be identified

and quantified. The following steps will be taken

to quantify the expected change.

The noise levels of the existing operations at

each site at the nearest sensitive locations have

been monitored. The operations were typical for

the existing operations at each site and the pro-

posed activities will be compared to the future

operations at a similar time of the year as activi-

ties are seasonal. The noise from proposed op-

erations was then predicted at the same receptor

locations and compared with the current noise

levels to ascertain the potential increase in noise

levels and therefore any noise impact on local

residents.

The prediction time period has been taken as

1900hrs to 2200hrs which is the same as the to-

tal measurement period in the sensitive part of

the evening.

The potential noise due to the site operations

consisted of

- Vehicular movements

- External plant and vents

- External sporting activities

- Noise break out from building

The potential noise level at each sensitive recep-

tor will be the summation of all proposed and ex-

isting individual noise sources, assuming the

noise sources are not correlated. This is then

compared to the typical existing noise sources.

The methodology for predicting the noise from

each noise source is as follows:

- Vehicular movements

Measurement for a vehicular movement is used

to calculate the noise level due to all vehicle

movements in the sensitive time period

- External ancillary plant and vents

The maximum permissible noise levels are de-

termined using the existing background noise

levels at the nearest sensitive receptors. The

plant is assumed to be operating continuously

during the sensitive period.

- External sporting activities

The typical noise levels at the nearest residences

are calculated assuming the activities are opera-

tional throughout the sensitive period.

- Noise break-out from buildings

This should be mitigated as far as practicably

possible through the use of well sealed door-

ways, windows and vents.

3.1 Haslingden Sports Centre

The existing noise sources at Haslingden Sports

centre are noise from

- External 5-A-Side football

- External ancillary plant and vents

- External tennis courts

- Noise egress from indoor sports hall

through the side access doors and from

the fitness suite through the ventilation

duct work.

- Car movements and noise

3.1.1 Causeway Head residences (M1)

Existing noise levels

The existing noise level at the Causeway Head

residences was measured during a 5-A-Side

football match. Also in operation was football

within the sports hall, fitness suite and the air

conditioning was in full operation. The noise

level at the Causeway Head residences was

53.3dB LAeq,T.

Proposed noise levels from operations

The only alteration in this section of the site is the

increase in car parking. A measurement was

taken at M3 of a car at 30m from M3 leaving the

existing car park. This noise level was 42dBA.

The nearest proposed car parking space is 10m

from the nearest residences. So using a correc-

tion for distance the noise level at 10m from a

single car movement, which lasted 1minute, can

be converted to a SEL (sound exposure level).

From the SEL a noise level for the busy period

can be determined using the number of predicted

car movements in a given period. Equation (1)

shows the calculation for a sound exposure level

from a noise level of know duration. For a car

movement at the residences the LAeq,T is 47dB at

10m and the SEL is 65dBA.

(1)

where T = Total event time period 60 seconds

To = Reference time period of 1 second

Using Equation (2) the LAeq,T for the busy period

can be determined as based on 19 extra move-

ments per hour in the busy periods. It seems




plausible to predict that the extra car movements

will be situated in the extra car parking near to

the Causeway Head residences. The busy pe-

riod has been indicated as 1600hrs – 2000hrs

and if this will indicate a worst case scenario

when used to represent activities during the sen-

sitive period of 1900hrs to 2200hrs. The car

movements assessed over this period give a

noise level of 42.2dB LAeq,T..

(2)

where T = total equivalent time period in seconds (14400)

n = number of noise events within time period, T (10) Figure 10

Noise level due to number of events with known SEL

3.1.2 Block of flats to the rear of sports hall (M2)

The current noise level at these residences due

to activities in the sports hall was monitored as

49.7dB LAeq,T. The distance from these flats to

the car park access route is the same as the dis-

tance between the nearest car parking space to

the nearest Causeway Head residences so the

42.2dB LAeq,T. for car movements can be as-

sumed representative of the noise level from car

movements at this location.

3.1.3 Mayfield Avenue residences (M3)

The tennis courts are the same distance from the

nearest residences as the Causeway Head resi-

dences are to the football pitch. So this noise

level will be used as the existing noise level from

operations at Haslingden Sports Centre. As the

nearest proposed car parking spaces are the

same distance as those proposed at the Cause-

way Head residences it is determined that local

amenity will also be retained.

3.2 Marl Pitts Swimming Pool

The existing noise sources at Marl Pitts Swim-

ming Pool are noise from the swimming pool,

noise from ancillary plant and vents and noise

due to car movements.

The proposed noise sources are 5 football

pitches to the rear of the swimming pool, a fitness

suite and extended car parking. The

3.2.1 Marl Pitts residences (M1)

The monitored existing noise level at these resi-

dences was 48.2dB LAeq,T. This was mainly due

to car movements and noise from the swimming

pool activities. It is assumed that the increase in

the traffic movements to the site of 66 in the busy

period between 1800hrs and 2000hrs will be

concentrated to the proposed area of parking

which is nearer to these residences. Based on a

SEL of 65 at 10m the noise level due to the extra

car movements is predicted as 44.6dB LAeq,T.

The assessment will assume that all the pro-

posed football pitches are in operation to give a

worst case scenario of operational noise. As the

football pitches will receive some sound attenua-

tion from the swimming pool building this has

been introduced to the calculations using meth-

odology outlined in Calculation of Road Traffic

Noise (CRTN) [1]. The residences on Marl Pitts

will have partial line if sight of two football pitches

and no line of sight of the remaining pitches.

From extrapolation of the noise level measured of

the football match at Haslingden Sports Centre a

noise level due to the football matches at these

residences is calculated.

3.2.2 Newchurch Road residences (M2)

The calculation method is similar to that of the

Marl Pitts residences. However, there is a

greater distance between the football pitches and

these residences. These residences are 90m

from the nearest football pitches which is 30m

further than M1 from the pitches. So they will

receive an increased sound attenuation of the

noise from the football pitches at M1 to M2 of

1.8dBA.

3.3 Summary of predicted noise levels

Receptor point

Existing

noise level,

LAeq,T

(dB)

Predicted

noise level,

LAeq,T

(dB)

Difference

in noise

level

(dBA)

Haslingden

Sports Centre

Causeway Head

residences 53.3 53.6 +0.3

Block of flats

behind sports hall 49.7 50.4 +0.7

Mayfield Avenue


Marl Pitts

Swimming Pool

Marl Pitts


Newchurch Road


Figure 11

Change in noise level at nearest residences to each site

Figure 12 shows the human auditory response to

changes in noise level taken from Design Manual

for Roads and Bridges: Volume 11 [2]. It can be

seen from this that the increase of the noise level




at the nearest residences surrounding each site

should be imperceptible.

Sound Level

Change

(dB(A))

Interpretaion

Subjective

impression

Impact

description

0.0 No change None

0.1 to 2.9 Imperceptible

change in loudness Slight

3.0 to 4.9 Perceptible change

in loudness Moderate

5.0 to 9.9 Up to doubling or

halving of loudness Substantial

10.0 or more

More than doubling

or halving of

loudness

Severe

Figure 12 Perceptibility of noise level increase from Design Manual

for Roads and Bridges Volume 11

3.4 Mitigation

3.4.1 Noise egress

It is recommended that noise from amplified mu-

sic within the fitness suites is at an acceptable

level. Ensure that any ventilation ducts are de-

signed to reduce the potential of noise egress

from the fitness suites.

All access doors and windows to the swimming

pools, sports halls and fitness suites especially

during sensitive evening hours should be well

sealed.

3.4.2 Noise from ancillary plant

Background noise levels were monitored at the

nearest sensitive receptors without influence of

noise from operations of the two premises,

shown in Figure 6 and Figure 8. These back-

ground noise levels will be used to determine the

maximum permissible noise level from ancillary

equipment. The background noise level has

been used due to ancillary equipment being left

on in the night time period. This methodology is

based on BS4142 [3].

A standard guidance criterion is that noise from

the ancillary equipment should be no more than

5dB below the existing background noise level at

the nearest residences.

It is recommended that the access doors and

external walls to the plant room should be acous-

tically treated and well sealed. The access doors

should only be used when necessary and remain

shut at all times.


As shown in Figure 6 the existing background

noise levels vary at the nearest residences. The

lowest monitored background noise level is 40dB

LA90,T at the residences close to M4. This resi-

dential dwelling will have direct line of sight of the

proposed plant room. To protect the local amen-

ity at this nearest residence the noise level from

the proposed plant room and any ancillary vents

should be no higher than 42dB LAeq,T @ 3m from

the plant room and extracts. This takes into ac-

count a correction for higher likelihood of annoy-

ance due to the potential of intermittency of the

noise from the plant and extracts (addition of 5dB

to noise level) and the distance attenuation of the

noise as the plant room will be 12m from the

nearest residences.

Noise from the plant room to the residences on

Causeway Head is not seen as an issue as any

mitigation applied to conserve amenity at the

residences at Mayfield Avenue will be more than

sufficient to prevent potential noise impact due to

the plant room to the Causeway Head residences


It is recommended that any proposed ancillary

equipment should be mounted on the façade fac-

ing away from the sensitive receptors towards the

proposed football pitches. A maximum noise

level of any proposed ancillary plant should be

68dBA LAeq,T @3m. The noise character of the

ancillary plant should be broad band in frequency

content and not tonal.

3.5 Noise from increased local traffic flow

At both sites the existing traffic flow on the adja-

cent main roads is quite large and the minimal

increase in traffic that is proposed to access the

sites will not increase the noise level on the main

roads by a significant amount.

4 CONCLUSIONS

A noise survey has been undertaken at the site of

Haslingden Sports Centre, Helmshore Road,

Rossendale, BB4 4DN and Marl Pitts Swimming

Pool, Newchurch Road, Rossendale, BB4 7SN

with the aim to assess the potential noise impact

from proposed alterations to local sensitive re-

ceptors near the existing sites. Noise measure-

ments of the existing noise climate have been

taken at the nearest residential dwellings and the

noise levels from proposed operations have been

predicted using measured and calculated data. It

is envisaged that noise due to the proposed al-




terations at both sites should be imperceptible at

the nearest residences. The following recom-

mendations have been made to ensure that the

local amenity is preserved at both sites in regards

to noise. The proposed ancillary equipment at

Haslingden sports centre should have a maxi-

mum external noise level of 42dB LAeq,T @3m.

The ancillary equipment at Marl Pitts Swimming

Pool should be mounted on the facade facing

away from the nearest residences and have a

maximum noise level of 68dB LAeq,T @3m. The

noise from the plant should also be broad band

and not tonal in frequency. It is recommended

that there is no noise egress from the operations

within the buildings such as swimming pools, fit-

ness suites and sports hall. All access doors

should be sealed well with this in mind. It is also

envisaged that increased noise on the main

roads from increased traffic flow at the sites will

be negligible.

5 REFERENCES

[1] Department of Transport and the Welsh Office,

Calculation of Road Traffic Noise

HMSO, London.1988

[2] Design Manual for Roads and Bridges

Volume 11: Stage 3: Environmental assessment tech-

niques, Part 7 HA 213/08

Highways Agency, 2010

[3] BS 4142:1997

Method for Rating industrial noise affecting mixed residen-

tial and industrial areas

British Standards Institute, 1997




APPENDIX

A1 DETAILS OF MEASURING EQUIPMENT

Equipment Description Maufacturer Type Number Serial No: Date calibrated

Calibration

Certification

Number

Class 1 Integrating Real Time 1/3

Octave sound analyzer Norsonics Nor140 1402754 16/04/2009 u5044

Calibrator Norsonics 1225 72889 17/05/2010 u6975

Microphone Norsonics 1225 72889 16/04/2009 u5043




A2 PROPOSED ALTERATIONS

A2.1 Haslingden Sports Centre

Ground floor outline

Extension outline

Ground floor in detail




First floor outline

First floor in detail




Plan View

Plant Room

N




A2.2 Marl Pitts Swimming Pool

Ground floor

First floor




Plan view

N




A3 CURRENT AND PROPOSED OPENING HOURS

A3.1 Haslingden Sports Centre

Day Current opening times Proposed opening times

Monday 8:00am – 10:00pm 7.00am- 10.00pm

Tuesday 8:00am – 10:00pm 7.00am- 10.00pm

Wednesday 8:00am – 10:00pm 7.00am- 10.00pm

Thursday 8:00am – 10:00pm 7.00am- 10.00pm

Friday 8:00am – 10:00pm 7.00am- 9.00pm

Saturday 8:45am – 6:00pm 8.00am- 5.00pm

Sunday 9:00am – 5:00pm 9.00am -5.00pm

A3.2 Marl Pitts Swimming Pool

Day Current opening times Proposed opening times

Monday 7:00am – 9:30pm 7.00am- 10.00pm

Tuesday 7:00am – 9:30pm 7.00am- 10.00pm

Wednesday 7.00am- 10.00pm 7.00am- 10.00pm

Thursday 7:00am – 9:30pm 7.00am- 10.00pm

Friday 7:00am – 9:30pm 7.00am- 9.00pm

Saturday 8:00am – 3:30pm 8.00am- 5.00pm

Sunday 9:00am – 5:30pm 9.00am -5.00pm




A4 GLOSSARY OF TERMS

A

Subscript used to denote the A weighting scale.

This is used to reflect the frequency response of

human hearing being more sensitive at speech

(mid) frequencies and less response at high and

low frequencies.

T

Time period of measurement usually in seconds.

LAeq,T

The A-weighted equivalent continuous sound

pressure level. The amount of sound energy

within a time varying sound pressure is equiva-

lent to a constant level within the same time pe-

riod. This is described mathematically as:

LA10,T

The A-weighted sound level exceeded for 10% of

the stated measurement period T. This is the

accepted parameter for measuring road traffic

noise.

LAE

Sound exposure level (also denoted SEL) for an

equivalent one second period.

LA90,T

The A-weighted sound level exceeded for 90% of

the stated measurement period T. This is the

accepted parameter for measuring background

noise.

dB

Abbreviation for Decibel: the unit of sound pres-

sure level.

Free-field

Far from the presence of any sound reflecting

objects other than the ground, usually taken to

mean at least 3.5m away.

Façade

At 1.0m away from a reflecting surface such as

the façade of a building. Façade noise levels are

3dB(A) higher than the free-field noise level

would be if the reflecting surface or building were

not there.

Specific Noise Level

The noise level of the noise source under investi-

gation.

Ambient Noise Level

Totally encompassing sound in a given situation

at a given time usually being composed of sound

from many sources near and far.

Residual Noise Level

The ambient noise remaining at a given position

in a given situation when one or more specified

noises are suppressed.

Background Noise Level

The sound pressure level of the residual noise at

the assessment position that is exceeded for

90% of the given time interval. This is indicative

of the continuous noise level without noise peaks

and accounts for the normal steady background

noise level at the measurement location. Nor-

mally represented by LA90,T.

Rating Level

The specific noise level plus any adjustment for

the characteristic features of the noise, for exam-

ple intermittency and the frequency content of the

noise.

Sound power level, Lw




noise.

Sound pressure level, Lp




noise.

where pA(t) = instantaneous sound pressure in Pascals at

time t.

p0 = reference sound pressure representing onset

threshold of hearing of 20μPa




A5 CTRN GRAPHS




A6 SOUND LEVELS PRODUCED BY TYPICAL NOISE SOURCES3

3 C. Hansen, Fundamentals of Acoustics, http://www.who.int/occupational_health/publications/noise1.pdf

Documents

NOISE ASSESSMENT HASLINGDEN SPORTS CENTRE, … · BB4 7SN Dan Clayton // BSc (Hons) Acoustics, AMIOA // [email protected] Summary A noise survey has been undertaken at the