Acoustic Expert Evidence Prepared by Frank Butera · 2019-07-16 · Acoustic Expert Evidence Prepared by Frank Butera Instructed By Maddocks Lawyers on ... my curriculum vitae with

Acoustic Expert Evidence

Prepared by Frank Butera

Instructed By Maddocks Lawyers on behalf of

Banyule City Council, City of Boroondara and

City of Whitehorse.

Maddocks Lawyers on behalf of Banyule City Council, City of Boroondara and City of Whitehorse.

North East Link Project – Joint Inquiry and Advisory Committee

Expert Witness Statement

15 July 2019

Job number 268222-00

Arup Australia Pty Ltd ABN 76 625 912 655

Arup

Sky Park

One Melbourne Quarter

699 Collins Street

Docklands VIC 3008

Australia

www.arup.com



Expert Witness Statement | |

J:\268000\268222-00 MADDOCKS NEL\WORK\ACOUSTICS\EVIDENCE ISSUED\FRANK BUTERA EVIDENCE NEL 15 JULY 2019.DOCX

Contents Page

1 Information Pursuant to Practice Note – Expert Evidence 2

2 Introduction 5

3 Technical Report C 6

4 Conclusion 17

Appendices

Appendix A

CV - Frank Butera

Appendix B

Letter of Instructions

Appendix C

Acoustic Terminology





Page 2

1 Information Pursuant to Practice Note – Expert

Evidence

1.1 Name and Address

1.1.1 My name is Frank Butera. I am an Associate with Arup Australia Pty Ltd (Arup)

practicing from 699 Collins Street, Docklands.

1.2 Qualifications and Expertise

1.2.1 I am an Acoustic Consultant. I gained my Bachelor of Science (Applied Physics)

from RMIT University in 1996. I am a member of the Australian Acoustical

Society and have been practicing as an acoustic consultant since 1996. A copy of

my curriculum vitae with relevant experience is attached in Appendix A.

1.3 Area of Expertise

1.3.1 My areas of expertise are in predicting, measuring, and assessment of

environmental noise levels for a wide variety of sources such as industry,

commercial, road, rail and aircraft.

1.4 Instruction which defined the scope of this report

1.4.1 I have been instructed by Maddocks Lawyers on behalf of Banyule City Council,

City of Boroondara and City of Whitehorse. Detailed in Appendix B is my Letter

of Instructions dated 26 June 2019 followed by my response to questions in

Paragraph 4.

1.5 Facts, matters and assumptions relied upon

1.5.1 In the course of all my investigations I have:

a) Reviewed Environment Effects Statement – Chapter 11 Surface noise and vibration.

b) Reviewed Environment Effects Statement – Technical Report C Surface Noise and Vibration and Appendices A – M, prepared by SLR dated 10 April 2019 (Technical Report C)

c) EES Map Books

1.6 Documents taken into account

1.6.1 The following documents have been used for reference:

a) VicRoads – Traffic Noise Reduction Policy (2005)





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b) AS2107:2016 Acoustics – Recommended design sound levels and reverberation times for building interiors

c) NSW Road Noise Policy (RNP) and the NSW EPA entitled Environmental Criteria for Road Traffic Noise

d) ISO 9613 – 2:1996 Acoustics – Attenuation of sound during propagation outdoors.

e) State Environmental Protection Policy (Control of Noise from Commerce, Industry and Trade) No. N-1 (SEPP N-1)

f) EPA Publication 1254 – Noise Control Guidelines

g) EPA Victoria – Environmental Guidelines For Major Construction Sites. Publication 480 (1996)

h) EPA NSW Industrial Noise Policy, 2000

i) EPA NSW Industrial Noise Policy, 2017

j) Submission on North East Link Project: Environment Effects Statement Works Approval Application

k) Draft Planning Scheme Amendment dated 7 June 2019

l) IAC Report on Preliminary Matters and Further Information Request.

1.7 Identity of persons undertaking this work

1.7.1 I prepared this report with the assistance of the following at Arup:

Staff member Title Tasks

Kym Burgemeister Principal Completed a review of the evidence

Willem Gouthro Associate Completed a review of the evidence

1.8 Summary of my opinions

1.8.1 Key findings from the assessment are listed below:

1.8.2 I accept that the level of traffic noise modelling/calculations is adequate for an

EES assessment at the planning and approvals stages of the project. However, it

is possible that noise mitigation treatments have been under-estimated. The

documented noise mitigation presented in Technical Report C is to be considered

as preliminary minimum requirements.

1.8.3 Technical Report C details noise monitoring locations along the proposed

alignment. In general, the selected noise monitoring locations are appropriate.

However, there are deviations from the VicRoads policy1 when selecting suitable

periods based on metrological conditions. Technical Report C accepts wind

speeds between 3 – 5 m/s. This contradicts VicRoads policy. Higher wind speeds

may produce higher ambient noise levels. The increased noise levels have the

potential to skewer the outcomes of the noise assessment. This includes

1 VicRoads Victoria, “Traffic Noise Measurement Requirements for Acoustic Consultants”, Victoria, 2011.





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understanding the existing background noise level at noise sensitive receivers,

developing a “calibration factor”, achieving a reasonable level of confidence for

the noise model and designing noise mitigation such as noise barriers.

1.8.4 It is suggested that IAC consider night-time noise limits to “fill the gap” in the

VicRoads noise limit between 00.00 hrs – 06.00 hrs (Midnight – 6.00 am). An

approach is to acknowledge the findings of the NSW Road Noise Policy.

1.8.5 There is significant dependence on the use of OGA and the resulting noise

reduction, EPR NV1 must consider the use and maintenance of OGA. I

recommend that EPR NV1 details that the performance of OGA be maintained to

at least minus (-) 3 dB for the life of the project.

1.9 Declaration

1.9.1 I have made all the inquiries that I believe are desirable and appropriate and no

mattes of no matters of significance which I regard as relevant have to my

knowledge been withheld from the Panel.

Yours Sincerely

Frank Butera

Associate





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2 Introduction

2.1 Project Overview

2.1.1 North East Link (NEL) is a proposed new freeway road connection that travels

mostly north-south from the M80 Ring Road (Metropolitan Ring Road) to the

Eastern Freeway. The project includes upgrades and new road connections at the

Greensborough and Eastern Freeway interfaces. It is proposed to also include

upgrades to the Eastern Freeway.

2.1.2 The following sections describes the North East Link alignment:

2.1.2.1 M80 Ring Road to Northern Portal – from the M80 Ring Road at

Plenty Road, and the Greensborough Bypass at Plenty River Drive,

North East Link is proposed to extend to the northern portal near

Blamey Road that consist of above, below and at grade road sections.

2.1.2.2 Northern portal to Southern portal – from the northern portal the road

would transition into twin tunnels that would connect to Lower Plenty

Road via a new interchange, before travelling under residential areas,

Banyule Flats and the Yarra River to a new interchange at

Manningham Road. The tunnels are proposed to continue to the

southern portal located south of the Veneto Club.

2.1.2.3 Eastern Freeway - from Hoddle Street in the west through to

Springvale Road in the east, modifications to the Eastern Freeway

include road widening to accommodate future traffic volumes and new

dedicated bus lanes for the Doncaster Busway. There would also be a

new interchange at Bulleen Road to connect North East Link to the

Eastern Freeway.

2.1.3 I understand that a Joint Inquiry and Advisory Committee (IAC) has been

appointed for the project. I have been engaged by Maddocks Lawyers on behalf

of Banyule City Council, City of Boroondara and City of Whitehorse (Councils)

to undertake a review of North East Link Environment Effects Statement –

Surface noise and vibration impacts assessments.

2.1.4 Acoustic terminology used throughout this report is presented in Appendix C.





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3 Technical Report C

3.1 Overview

3.1.1 Technical Report C details the surface noise and vibration impacts of the North

East Link project. Technical Report C establishes noise and vibration project

noise limits from a combination of Victorian, National and International noise

documents. In particular, Technical Report C develops project noise and vibration

limits with reference to:

• Australian Standards, “Acoustics – Method for the Measurement of Traffic

Noise”, AS2702.

• VicRoads Victoria, “Traffic Noise Reduction Policy, VicRoads,” 2005

• VicRoads Victoria, “Traffic Noise Measurement Requirements for Acoustic

Consultants”, Victoria, 2011.

• EPA Victoria: Publication 1254, “Noise Publications,” 2017.

• EPA NSW, Interim Construction Noise Guidelines, EPA NSW 2009.

• British Standards, Code of practice for noise and vibration control on

construction and open sites. Vibration: BS5228-2:2014, British Standards

Institution.

• NSW EPA, NSW Road Noise Policy, NSW: NSW EPA, 2011.

3.1.2 It is my understanding that the surface noise and vibration Environmental

Performance Requirements (EPR) detailed within Technical Report C have been

developed with reference to combination of Noise Policies, Guidelines and

Standards.

3.1.3 For example, the development of EPR NV1 incorporates a component of

VicRoads policy2, a modified version of VicRoads Guidelines3 and NSW

Guidelines.4 Further details are provided in Section 3.3.

3.2 Background Noise Levels

3.2.1 For noise sensitive receivers in close proximity to the proposed alignment there

are likely to be four (4) significant sources of surface noise and vibration:

• Noise impacts from construction stages.

• Vibration impacts from construction stages.

• Mechanical noise from operational phases.

• Traffic noise impacts from operation phases.

2 VicRoads Victoria, “Traffic Noise Reduction Policy, VicRoads,” 2005 3 VicRoads Road Design Note 06-01 July 2010, Interpretation and Application of VicRoads Traffic Noise Policy

2005 4 NSW EPA, NSW Road and Maritime Services





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3.2.2 The intrusiveness and annoyance of noise sources is closely linked to the existing

ambient noise levels. As a result, understanding the existing conditions provides

an opportunity to set project noise limits, calibrate noise models and if required

recommend noise mitigation. Undertaking comprehensive fieldwork at

appropriately selected noise sensitive receivers to obtain the background noise

levels is fundamental when establishing accurate short and long-term project

noise limits.




periods based on metrological conditions.

3.2.4 Appendix D of Technical Report C, Page D-10 suggests that a VicRoads wind

speed filter was applied to exclude data samples greater than 3 m/s. However, the

captured and processed dataset presented in Appendix E includes data with

recorded wind speeds from the Viewbank weather station for wind speeds

between 3 – 5 m/s.

3.2.5 Technical Report - Appendix D, Page D5-D6, Paragraph 1 states that:

All of the wind data was adjusted as per the paper6 Converting Bureau of

Meteorology Wind Speed Data to Local Wind Speeds at 1.5 m Above Ground

Level. (Gowen Technical Paper)

3.2.6 The Gowen Technical Paper was published in 2004 and relies on the findings of

Section 4.2 of Australia Standard 1170.2-1989 “Structural Design Actions – Part

2: Wind Actions” (AS1170.2-1989). Further, the validation section of Gowen

Technical Paper suggests that:

For site-specific validations, a short-term measurement of local wind speed at the

noise monitoring location/ microphone height should be carried out over the 10

minutes prior to the BOM observation (ie the 10 minutes prior to the hour or half

hour, depending on the BOM measurement period). Preferably, the local wind

speed measurement should be conducted more than once, say at the time of noise

monitor set up and at collection. Local wind speed measurements should be

compared with the wind data from the BOM station measured at the

corresponding time to validate the wind speed correction. Note that further

corrections will need to be made if there are significant land topography effects

either at the measurement location or at the BOM meteorological station.

3.2.7 I note that, AS1170.2-1989 was superseded by AS1170.2-2011 with the most

recent amendment listed in 2017. AS1170.2-2011 applies an updated correction

factor for metrological mast wind gusts when compared to wind speeds less than

5 VicRoads Victoria, “Traffic Noise Measurement Requirements for Acoustic Consultants”, Victoria, 2011. 6 Converting Bureau of Meteorology Wind Speed Data to Local Wind Speeds at 1.5m above Ground Level.

Gowen, T., Karantonis, P., Rofail, T,. Proceedings of Acoustics 2004 Gold Coast Australia.





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3 m. Further the updated Standard refers to terrain/height multiplier to be applied

to “Wind Gusts” not the average wind speeds.

3.2.8 It is understood that a correction factor of 0.63 terrain/height multiplier was

applied to the wind data captured and presented in Technical Report C. In my

opinion the correction applied to the data is inconsistent with the methodology of

Gowen Technical Paper and is considered incorrect when referred to the current

Australia Standard AS1170.2-2011.

3.2.9 Caution is to be applied if the background noise levels obtained during the noise

monitoring period are to be considered when developing project noise limits or

model calibration factor.

3.2.10 If an accurate correlation between mast data and monitoring data has not been

developed, then all the wind speed data is to be returned to the original

unmodified value. In accordance with VicRoads guidelines, hourly wind speeds

in excess of 3 m/s are to be removed from the dataset.

3.2.11 It is good practise to obtain field data from three (3) “good weather days”, that is

with no rain and with wind speeds less than 3 m/s. Based on my experience, field

noise monitoring may at times require up to two (2) weeks per site.

3.2.12 If the wind speed data is to be returned to its original value, it is likely that there

will be an increased number of days and sites that are to be excluded from the

noise monitoring dataset. Noise monitoring data that does not comply with the

VicRoads methodology is to be excluded.

3.2.13 Based on my preliminary assessment the difference in measured background

noise level may be 0.5 – 1.5 dB less when compared to the documented

background noise level in Technical Report C. This is based on the background

noise monitoring dataset incorporating results that have been modified by a

correction factor of 0.63 and the dataset incorporates background noise levels that

include wind speeds of 3 – 5 m/s.

3.2.14 The difference is not considered excessive when establishing noise limits for

construction or mechanical services noise limits. However, it is likely to have an

impact to the noise modelling validation process, referred to as the “calibration

factor” detailed in Section 9.2 of Technical Report C. Consequently, the

difference in traffic noise level to noise sensitive receivers from 2018 to 2036

may be underestimated.

3.2.15 I suggest that lower background noise levels are likely when compared against

the dataset presented in Technical Report C. Hence, the change in noise level

from the existing year to the year of opening and beyond has increased

accordingly.

3.2.16 I understand the noise modelling has applied a single figure calibration validation

value to the entire alignment when developing the noise model. If background

noise levels have not been appropriately captured, then there is the likelihood that

the model calibration is effected and the model confidence may be overvalued.





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Noise mitigation documented on this basis may be under-estimated. This may

result to increased number of impacted residential properties, higher noise

barriers or increased number of at-property noise mitigation treatment when

compared to the existing outcomes in Technical Report C.

3.2.17 Since the calibration factor is “carried over” to the future alignment, it is likely

that there will be alternative outcomes of the “with project” and “no project”

scenarios. I suggest that the noise barrier locations and heights proposed by

Technical Report C be adopted as preliminary minimum noise barriers, until the

measured background noise level measurements have been completed in

accordance with the methodology approved by VicRoads.

3.2.18 As detailed in Environmental Performance Requirement (EPR) NV2, I

recommend that before the project proceeds that background and existing traffic

noise levels be completed as detailed by the methodology prescribed by

VicRoads. Further, project noise limits and noise mitigation be applied based on

the further background and existing traffic noise measurements.

3.3 Noise Model Confidence and Calibration

3.3.1 It is understood that calibration of the noise model is provided based on

comparison of the predicted and measured noise level at 18 locations. This is

significantly less than the 32 locations monitored but may be considered

acceptable for comparative assessment.

3.3.2 The procedure for calibration is satisfactory and the resulting

minus (-)1.9 dB correction factor is acceptable based on my previous experience

of CoRTN over prediction in Australian conditions.

3.3.3 However, the differences between calculated and measured noise levels vary

significantly and indicate that there may be errors with the noise model that may

not be addressed by a single calibration factor.

3.3.4 Areas where the noise model under (or over) predicts by more than 5 dB indicates

that the noise model may be accounting for noise barrier or terrain that does not

reflect the acoustic environment at the receiver location.

3.3.5 If noise barrier or terrain is carried into noise modelling for future scenarios, it is

likely that the noise barrier design has been under-estimated.

3.3.6 After calibration, comparison of predicted and measured noise levels for the M80

and Eastern Freeway differ by between 9 dB and 5 dB respectively. Without

reasonable explanation, these deviations are be investigated and where

appropriate the noise model may require adjustment.





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3.4 Operational Traffic Noise Limits - LA10,18hr 63 dB

3.4.1 Environmental Performance Requirement (EPR) NV1 has been developed from a

combination of VicRoads policy and other documents7. The LA10,18hr 63 dB noise

limit to Category A and Category B buildings has been successfully adopted for

new and existing road projects in Victoria. Including the recently approved West

Gate Tunnel and Mordialloc Bypass projects.

3.4.2 EPR NV1 limits the use LA10,18hr 63 dB traffic noise limit and suggests alternative

noise treatments which include at-property mitigation.

3.4.3 Based on my experience with the VicRoads policy, any deviation from

implementing noise barriers to control traffic noise requires an appropriately

developed Reasonable and Feasible assessment. It is unclear if Technical Report

C has completed Reasonable and Feasible assessment or if VicRoads has had

input into assessment methodology.

3.4.4 It is unclear within EPR NV1 as to the extent of:

“Where external traffic noise cannot be mitigated through project design

solutions to meet the criteria outlined in paragraphs (a) and (b), at-property

treatments may be required”.

In my opinion the use of at-property treatment is to be clearly defined within the

EPR. If the at-property trigger is not developed appropriately then it remains

unclear when LA10,18hr 63 dB is to be applied to the residential property or when

the at-property target is to be achieved.

3.4.5 Technical Report C suggests that noise barriers will be limited to 10 m in height

above existing or future terrain. Based on my experience it is uncommon for

VicRoads to restrict the height of noise barriers in Victoria.

3.4.6 Although, Technical Report C details the proposed noise barriers, it does not

disclose the height of noise barriers required to achieve LA10,18hr 63 dB to all

impacted residential properties. Technical Report C provides a combination of

aspiring to achieve LA10,18hr 63 dB in conjunction with at-property treatment.

3.4.7 VicRoads traffic noise policies also applies to property developers8 when

converting land for residential or similar use. For property developers VicRoads

is generally the Referral Authority. In most cases VicRoads approves the

construction of noise barriers to comply with a traffic noise limit of LA10,18hr 63

dB to future dwellings ten (10) years after site has been developed.

3.4.8 The VicRoads policy has consistently applied to the lowest habitable room.

Property developers generally accept the upper levels may also be impacted by

7 Refer to footnote 1, 2 and 3. 8 VicRoads Requirements for developers – Noise sensitive uses.





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traffic noise and provide at-property noise mitigation to achieve the internal noise

limits set within AS21079.

3.4.9 Based on my experience, it is uncommon for VicRoads to approve a residential

development that abuts a VicRoads owned road that does not demonstrate

compliance with LA10,18hr 63 dB to the lowest habitable room of the dwelling.

Compliance for the property developer is generally achieved by construction of

adequate noise barriers or positioning non-sensitive use or rooms to the most

impacted façade.

3.4.10 In my opinion, compliance with LA10,18hr 63 dB traffic noise limit, externally to

the lowest habitable room does not provide a tranquil aural environment.

Compliance with the noise limit suggests that traffic noise is clearly audible and

the dominant noise source to the noise sensitive receivers.

3.4.11 Noise levels to upper levels of multi-level dwellings are likely to experience noise

levels 5 – 10 dB higher than would be experienced to ground floor levels.

3.4.12 LA10,18hr 63 dB traffic noise limits excludes an assessment in noise level from

00.00 hrs – 06.00 hrs (midnight – 6.00 am). No EPR has been developed to assess

traffic noise during the night-time period. As a result, there is no protection to the

community during sleeping hours and since the noise period is not assessed it is

not monitored.

3.4.13 By comparison, NSW Road Noise Policy limits night-time 22.00 hrs – 07.00 hrs

(10.00 pm – 7.00 am) traffic noise levels for new freeways to existing residential

properties at LAeq (9 hour) 50 dB. The LAeq (9 hour) 50 dB is approximately 10 dB less

than LA10,18hr 63 dB.

3.4.14 I recommend for the NEL project a night-time noise limit be considered by IAC.

Further details are provided in Section 3.6.

3.5 Operational Traffic Noise Limits – Road Receivers &

Surface Correction

3.5.1 It is my understanding that traffic noise modelling has been undertaken

considering Noise Model Inputs detailed in Table G-13 of Appendix G –

Technical Report C. There are two input parameters that require further attention,

these are the assumed height above existing terrain of the noise sensitive receiver

(Road Receivers) and minus (-)3 dB Road Surface Correction applied to the

proposed road surface for open-graded asphalt (OGA)

3.5.2 Technical Report C suggests that site inspections of noise sensitive receivers were

limited. However, the noise modelling allocates receiver heights at 1.5 m above

existing terrain level to all receivers.

3.5.3 Acknowledging the undulating terrain particularly between M80 and Lower

Plenty Road it is unlikely that 1.5 m above the existing terrain conforms with

9 AS2107 - Acoustics - Recommended design sound levels and reverberation times for building interiors





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VicRoads10 guidelines. VicRoads suggests that the noise monitoring position,

which is also to be accepted as the noise modelling position to be:

The microphone shall be substantially unobstructed (approx 135 degrees) and

shall be located externally, one metre from the centre of the most exposed

window of a habitable room on the lowest habitable level of the building under

consideration.

In practice the microphone/receiver position is to be located 1.5 m above the

finished floor level of the lowest habitable room.

3.5.4 If noise modeling has been completed for receiver positions 1.5 m above ground

level and site conditions suggest that the “centre of the most exposed window” is

higher than 1.5 m above ground level. Then it is likely that noise mitigation to the

noise sensitive receivers has been underestimated. This is likely to result in higher

noise barriers than has been documented in Technical Report C.

3.5.5 For example, if a dwelling has a finished floor level of 800 mm above ground

level then the receiver position is 2.3 m above existing ground level. If a

4 m noise barrier is required to mitigate the dwelling to LA10,18hr 63 dB then based

on an increased height onsite the noise model has underestimated the requirement

for a noise barrier by 800 mm.

3.5.6 It is suggested that prior to commencing the project EPR NV1 is to accurately

acknowledge the microphone/receiver position and noise mitigation is to be

designed accordingly.

3.5.7 Open Graded Asphalt (OGA) provides beneficial reductions of traffic noise. A

correction of minus (-) 3 dBA has been applied in the modelling of traffic noise

for the project. A 3 dB reduction at the source is considered to be significant and

without its noise reduction contribution, additional noise mitigation (higher noise

barriers) will be required.

3.5.8 It is widely accepted that traffic noise reduction provided by OGA typically

reduces over time due to progressive degradation of the road surface.

3.5.9 It has been assumed that the road surfaces throughout the project will be regularly

maintained to a level sufficient to sustain the acoustic benefit provided by the

OGA.




at least minus (-) 3 dB for the life of the project. VicRoads11 design note also

10 VicRoads Victoria, “Traffic Noise Measurement Requirements for Acoustic Consultants”, Victoria, 2011. 11 See Footnote 2.





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details the OGA is to be maintained to reduce the appropriate noise reduction for

the life of the project.

3.5.11 An alternative approach adopted by the recently approved West Gate Tunnel

Project was to set the traffic noise limit of LA10,18hr 63 dB for twenty (20) years

after opening.

3.6 Operational Traffic Noise Limits – CoRTN

3.6.1 EPR NV1 proposes to include an assessment that investigates “do nothing” or

future existing scenarios. These scenarios rely on maintaining the same road

network with the assumption of increased traffic flow. CoRTN is an effective

traffic noise modelling algorithm and was developed for continuous traffic flow

for speeds greater than 75 km/hr.

3.6.2 Appendix K of the Technical Report C provides noise maps for 2036 “no

project”. These plots are compared against the existing (2018) traffic noise levels.

By subtracting the difference, Technical Report C demonstrates the change in

noise level based on without the impact of the proposed alignment.

3.6.3 Table G-13 of Appendix G – Technical Report C (Noise Model Inputs) does not

clarify how CoRTN has been modified or applied for 2018 (Existing) & 2036

(Future-Existing) scenarios. Considering both scenarios consist of segments that

incorporate traffic light scenarios. The stop/start traffic noise is largely

contributed to engine and exhaust noise and low traffic flow conditions for

various periods of the day.

3.6.4 Based on my experience, CoRTN does not accurately predict traffic noise levels

for road networks that incorporate traffic lights. It is suggested that an additional

calibration process be implemented to establish noise levels for Non-Project

Roads.

3.7 Operational Traffic Noise Limits – Night-time noise

limits

3.7.1 It is understood that night-time truck curfews currently apply to the road network

in the study area. On that basis it is appropriate to minimise the impact of truck

noise to noise sensitive receivers during the night-time period. EPR NV1 does not

comment on the night-time noise limits.

3.7.2 In the absence of Victorian or National night-time traffic noise limits, it is

suggested to investigate the recent findings of the World Health Organization

(WHO).

3.7.3 In 2018, the World Health Organization Regional Office for Europe published the

Environmental Noise Guidelines for the European Region (WHO Guidelines),

which recommends noise criteria for a range of environmental noise sources,

including traffic noise.





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3.7.4 I am not aware of any proposal for the 2018 WHO Guidelines to be incorporated

into any noise legislation or guidelines in Victoria, however since Technical

Report C does not address night-time noise limits. It is suggested that IAC

consider the findings of the WHO Guidelines.

3.7.5 The WHO Guidelines recommend the use of Lden (Leq over the day, evening and

night periods, with penalties applied for evening and night period noise levels).

The WHO Guidelines recommend a 24-hour period road traffic noise limit of

Lden 53 dBA and for the night period a limit of Lnight 45 dBA.

3.7.6 Technical acoustic papers and a selection of Arup’s traffic noise measurement

data have been referenced to derive the approximate difference between the Lden

metric used in the WHO Guidelines and the L10,18hr metric used in the VicRoads

noise limit. This analysis indicated that the Lden is likely to be of the order of

3 dBA higher than the L10,18hr for the same traffic noise measurement.12

3.7.7 The analysis outlined above indicates that the traffic noise limits recommended in

the WHO Guidelines are much more stringent than the VicRoads, with traffic

noise limits approximately 13 dBA lower, i.e. instead of the VicRoads

L10,18hr 63 dBA limit for residential properties, the WHO Guidelines may require

a limit of the order of L10,18hr 50 dBA.

3.7.8 It is accepted that a WHO noise limit of L10,18hr 50 dBA is stringent when

compared to current practices. However, VicRoads methodology does not assess

traffic noise levels between 00.00 hrs – 06.00 hrs (Mid-night – 6.00 am). Since

there are no traffic noise commissioning measurements proposed for 00.00 hrs –

06.00 hrs the night-time truck or traffic noise limits have not been assessed by the

Technical Report C.

3.7.9 It is suggested that a balanced approach be considered that acknowledges the

existing curfew periods and whilst developing a practicable night-time noise

limit.

3.7.10 As detailed in Section 3.4.13 NSW Road Noise Policy limits night-time 22.00 hrs

– 07.00 hrs (10.00 pm – 7.00 am) traffic noise levels for new freeways to existing

residential properties at LAeq (9 hour) 50 dB. I recommend for the NEL project that

IAC consider adopting a night-time limit similar to the widely accepted NSW

Road Noise Policy.

3.7.11 Particularly for the night-time period, the use of engine brakes in urban areas is to

be avoided. As a result, EPR NV14 is to be modified to eliminate or restrict the

use of exhaust engine brakes.

12 An approximation and would be subject to significant variation but is considered an appropriate estimation for

the purposes of this comparison exercise.





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3.8 Operational Traffic Noise Limits – Summary


EES assessment at the planning and approval stages of the project. However, it is

possible that noise mitigation treatments have been under-estimated.


VicRoads noise limit. An approach is to acknowledge the findings of the NSW

Road Noise Policy.

3.9 Operational Noise Limits – Fixed Mechanical

Infrastructure

3.9.1 Fixed mechanical infrastructure generally refers to tunnel ventilation system and

portal ventilation fans. Technical Report C has completed an assessment and

provides noise limits in accordance with State Environment Protection Policy

(Control of Noise for Commerce Industry and Trade) No. N-1 (SEPP N-1).

3.9.2 It is widely acknowledged that EPA will introduce a replacement for SEPP N-1

noise policy on 1 July 2020. However, to date the methodology and findings of

the proposed noise policy have not been exhibited.

3.9.3 Considering the forth coming replacement noise policy it is suggested that EPR

NV6 and EPR NV7 be updated to incorporate wording to accept the SEPP N-1

replacement document.

3.10 Construction Noise and Vibration

3.10.1 Construction noise and vibration impacts (including construction traffic) has the

protentional to impact the noise sensitive community.

3.10.2 Technical Report C details that during most construction phases there will be

multiple and significant exceedances of the project construction noise limits.

3.10.3 EPR NV3, EPR NV4, EPR NV8, EPR NV9 and EPR NV10 have been developed

to control construction noise and vibration. I understand that the Independent

Environmental Auditor must verify Unavoidable Works. A similar approach has

been adopted for recent infrastructure projects in Victoria. For example, the

Melbourne Metro project.

3.10.4 To compliment the EPR NV3, I recommended that that extensive construction

noise and vibration scenarios be completed to understand severity of the noise

impacts to the community. Digital noise and vibration modelling of the proposed

activity is to be undertaken and assessed prior to the works progressing to the

construction phase. A similar approach has been adopted for the Melbourne

Metro project.





Page 16

3.10.5 Reporting the results of digital assessment is to be approved by the Independent

Environmental Auditor. It is suggested that EPR NV3 be updated to incorporate

digital assessment and approval processes.





Page 17

4 Conclusion


EES assessment at the planning and approval stages of the project. However, it is

possible that noise mitigation treatments have been under-estimated and are to be

considered as preliminary minimum requirements.




periods based on metrological conditions. Technical Report C accepts wind

speeds between 3 – 5 m/s. This contradicts VicRoads policy. There may be higher

ambient noise levels associated with increased wind speeds. The increased noise

levels have the potential to skewer the outcomes of the noise assessment. This

includes understanding the existing background noise level at noise sensitive

receivers, developing a “calibration factor” for the noise model and designing

noise mitigation such as noise barriers.


VicRoads noise limit. An approach is to acknowledge the use of findings of the

NSW Road Noise Policy.




at least minus (-) 3 dB for the life of the project.

4.1.5 If noise modeling has been completed for receiver positions 1.5 m above ground

level and site conditions suggest that the “centre of the most exposed window” is

higher than 1.5 m above ground level. Then it is likely that noise mitigation to the

noise sensitive receivers has been underestimated. This is likely to result in higher

noise barriers than has been documented in Technical Report C.

4.1.6 The procedure for calibration is satisfactory and the resulting

minus (-)1.9 dB correction factor is acceptable based on my previous experience

of CoRTN over prediction in Australian conditions. However, the differences

between calculated and measured noise levels vary significantly and indicate that

there may be errors with the noise model that may not be addressed by a single

calibration factor.

4.1.7 VicRoads noise policy applies to receiver positions located at ground level. It is

unclear what is proposed to attenuate traffic noise, to noise sensitive receivers of

the upper levels of multi-storey dwellings.

13 VicRoads Victoria, “Traffic Noise Measurement Requirements for Acoustic Consultants”, Victoria, 2011.

Appendix A

CV - Frank Butera

H:\CV\0800CV FOR FRANK BUTERA APRIL 2019 .DOCX www.arup.com

Frank Butera

Profession

Acoustic Consultant

Current Position

Associate

Joined Arup

2006

Years of Experience

24

Nationality

Australian

Qualifications

BSc Applied Physics

Masters Module – University of Cambridge ( UK) – Sustainability Leadership

Professional Associations

Member of the Australian Acoustical Society

Member of the New Zealand Acoustical Society

Executive Board Member, Victorian Planning and Environmental Law Association (VPELA)

Committees

Executive Board Member 2013 - Present, Victorian Planning and Environmental Law Association (VPELA)

Publications

Butera, F. and Morris, N (2003), Acoustic Planning of Australian Inner City Areas - An innovative Approach, Proc. Eight Western Pacific Acoustics Conference (WESPAC)

Butera, F. and Hewett, K (2012), Acoustic Performance of Louvred Facades for Brisbane Domestic Airport. An integrated approach. Internoise 2012, New York, USA

Frank Butera is an Associate with Arup and is located in Melbourne. Frank gained his BSc in Applied Physics at RMIT University, Melbourne. In 2006 Frank joined Arup in Sydney; he led the Sydney acoustics group from 2008 before returning to Melbourne in 2010.

Frank has over 20 years’ experience in consulting on diverse projects in areas of architectural acoustics, building noise and vibration control, and environmental noise analysis. He achieves successful project delivery by seeking economical solutions that utilise best practice analytical technology leading to practical implementation.

Frank is a strong communicator; he delivers sound technical ability, global perspective and a commitment to excellence in acoustic planning and design.

Frank has provided acoustic consulting advice for virtually every type of building or major development project over the course of his career. He has particular experience with large scale environmental impact projects and transportation noise.

Frank has significant experience in the assessment of aircraft, transportation and environmental noise modelling, measurement and analysis. Frank has also been responsible for noise mitigation on infrastructure projects throughout Australia.

Frank is Arup Acoustics’ representative for projects with Commonwealth of Australia, in particular the Department of Defence. Frank has obtained SECRET clearance.

Frank has significant experience in combing acoustics and sustainability principles for large scale projects. Frank has completed a Masters in Sustainability Leadership from University of Cambridge.

Frank also has extensive experience in providing expert evidence in Victoria, New South Wales and Tasmania.

Relevant Projects

Great Northern Highway – Western Australia Since 2016 Frank has participated and lead segments of the 200 kms long Great Northern Highway including the recently completed EIS Noise Chapter for Muchea to Wublin Upgrade and Bindoon Bypass. Frank coordinated noise surveys, traffic noise modelling and reporting.

Melbourne Metro One Project Melbourne Metro is a 10 km underground twin tunnel project through Melbourne CBD. Arup is engaged to deliver the engineering for the project. Frank has provided noise and


Butera, F., Burgemeister, K., Fisher, K.. and Mounter, D., Using Wind Farm Noise Auralsisations for Effective Community Consultation. Internoise 2014 Melbourne, Australia

vibration support during the planning and construction phases of the project.

Queensland Water Infrastructure – Traveston Section Bruce Highway

Completed an assessment of the potential noise and vibration impacts due to the proposed relocation of the Bruce Highway. Assessment incorporated community consultation traffic noise and vibration modelling and predictions.

South Sydney Freight Line, Fairfield, NSW

Undertake a supplementary acoustic assessment for the proposed South Sydney Freight Line (SSFL), incorporating additional noise predictions and an assessment of the acoustic impact of the SSFL on noise sensitive receivers located within the boundaries of Fairfield City Council, including noise contour plots.

Airport Link – Brisbane

Review acoustic modelling and noise control features for the design of a new freeway from Brisbane CBD to the Brisbane Airport. Frank provided input into the design of noise barriers, portal entrances and tunnel exhaust stacks.

Springvale Road Grade Separation

Baseline noise and vibration measurement was undertaken at properties likely to be affected by the proposed grade separation. A broad acoustic model was created and adjusted based on the measurement outcomes to provide a broad understanding of the existing noise environment through the use of noise contours. Comments and in principle noise mitigation options were provided taking into account the draft rail noise policy.

Tintenbar to Ewingsdale Route Selection, NSW

Long term road traffic noise monitoring, site survey and attended spot measurements were conducted for 30km of road to assist in preferred route selection for the Tintenbar to Ewingsdale upgrade. The Ewingsdale to Tintenbar upgrade will join the proposed Ballina Bypass to the existing dual carriageway at Ewingsdale. Long term noise logging and attending noise measurements were conducted.

Hydro Tasmania – TasWind Tasmania/King Island

Undertake pre-feasibility noise and vibration impact assessment for Hydro Tasmania. Frank is the Project Manager involved in capturing wind turbine noise data and presenting the findings of auralisation and modelling to the community of King Island.

T1 Perth International Departures Expansion and Domestic Facilities Frank was the acoustic leader for the $160M terminal development responsibilities included aircraft noise measurements, acoustic planning, facade and sound insulation and room acoustics recommendations.

Air Services One-Sky Melbourne & Brisbane Frank lead the acoustic design for Melbourne and Brisbane – One Sky projects. The facility will house Air Services air traffic


control staff. Responsibilities included reviewing and re-designing previous acoustic input. Providing acoustic recommendations to multiple noise sensitive areas adjacent to airport facilities including, Control Room and Sleep Rooms.

Melbourne Airport Terminal 4 Expansion Arup’s provided multi-disciplinary building and civil engineering for the new Terminal 4 and its expansion of the existing facilities. Frank is the acoustics and PA design Project Manager for Arup. The project included acoustic advice on sound insulation, mechanical services noise treatment, internal finishes, loudspeaker systems design.

Melbourne Jet Base – Melbourne Airport

Frank is leading the acoustic design for a Private Hanger terminal at Melbourne Airport. The facilities consists of hanger areas, function, lounge, presentation and customs space. It has been designed as a premium service facility.

Murray Goulbourn Co-Operation – Multiple Sites in Victoria Frank continues to lead noise impact assessments for multiple Murray Goulbourn milk plants throughout Victoria. Frank has prepared specification for tenders and assisted with consultation with manufactures, Council and the community.

Midfield Group – Warrnambool, Victoria Frank completed a noise impact assessment for a milk drying and cold store facility. The application was considered by Planning Panels Victoria in conjunction with three rezoning applications. The noise assessment consisted of undertaking 3D noise modelling and assessing the impact to the nearby noise sensitive community. Frank recommended noise control treatment to meet proposed noise limits. Expert evidence was presented at the panel hearing. Frank’s evidence was accepted by the Panel.

BHP Billiton – BHP Olympic Dam Desalination Plant, Port Bonython, South Australia

In 2008, Frank led the assessment of environmental impacts from buried-charge underwater blasting associated with construction of a desalination plant, including prediction of underwater blast and shock waves, prediction of ground vibration and air overpressure from blasting at residential receivers on-land, and assessment of impacts of blasting on marine life.

Victorian Desalination Plant – Wonthaggi

Responsible for the assessment of underwater noise and the impact to the surrounding marine environment, due to marine construction activity. Assessment includes works associated with the tunnel boring machines and drilling works. Development of appropriate marine noise limits.

Basslink Interconnector, Victoria/Tasmania

Investigate background, construction and operational noise levels to ensure that the proposed noise levels comply with the noise limits for both rural Victoria and Tasmania. Provide an acoustic assessment chapter that was incorporated within the Integrated Impact Assessment Statement (IIAS). Undertake a review of


marine construction activity and the effect associated marine from construction activity associated with project. Prepare and present expert witness statement to Planning Panels Victoria.

Appendix B

Letter of Instructions

[7849160: 24392855_1]

Interstate offices Canberra Sydney

Affiliated offices around the world through the Advoc network - www.advoc.com

Email Letter

From Date Terry Montebello 26 June 2019 Direct Email 03 9258 3606 [email protected]

To Organisation Email Frank Butera Arup [email protected]

Our Ref TGM:7849160 North East Link Inquiry and Advisory Committee Hearing Dear Mr Butera We continue to act for Banyule City Council (Banyule), City of Boroondara (Boroondara) and City of Whitehorse (Whitehorse) (collectively, the Councils) in relation to the Joint Inquiry and Advisory Committee (IAC) for the North East Link (Project). We are instructed to engage you to provide expert evidence in the area of noise and vibration. The IAC has been appointed:

▪ to hold an inquiry into the environmental effects of the Project under section 9(1) of the Environmental Effects Act 1978; and

▪ to review the draft planning scheme amendment prepared to facilitate the Project under section 151 of the Planning and Environment Act 1987.

Further details regarding the role of the IAC is set out in paragraphs 1 and 2 of the Terms of Reference. The biography for each committee member of the IAC is available here. The IAC will hold a public hearing commencing on 25 July 2019. Scope of Instructions

You are instructed to:

1. review the Ministerial Guidelines for assessment of environmental effects under the Environmental Effects Act 1978 (2006);

2. review the exhibited North East Link Environment Effects Statement (EES) documents, relevant to your area of expertise;

3. review:

(a) the Councils submission on the EES, dated 7 June 2019;

Lawyers Collins Square, Tower Two Level 25, 727 Collins Street Melbourne VIC 3008 Australia

Telephone 61 3 9258 3555 Facsimile 61 3 9258 3666

[email protected] www.maddocks.com.au

DX 259 Melbourne

https://s3.ap-southeast-2.amazonaws.com/hdp.au.prod.app.vic-engage.files/3115/5496/2888/Signed_ToR_for_NEL_IAC_S8NS16AD19041115320.pdf

https://s3.ap-southeast-2.amazonaws.com/hdp.au.prod.app.vic-engage.files/2715/5770/0330/North_East_Link_IAC_Biographies.pdf

https://www.planning.vic.gov.au/__data/assets/pdf_file/0026/95237/DSE097_EES_FA.pdf


https://northeastlink.vic.gov.au/environment/environment-effects-statement-ees/environment-effects-statement-documentation

https://s3.ap-southeast-2.amazonaws.com/hdp.au.prod.app.vic-engage.files/9915/6074/7490/Submission_716_Banyule_City_Council_Boroondara_City_Council_and_Whitehorse_City_Council.pdf

[7849160: 24392855_1] page 2

(b) the IAC report on Preliminary Matters and Further Information Request; and

(c) any other submissions or documents we subsequently refer to you;

4. prepare an expert witness report that contains your opinion on the following matters, as relevant to your area of expertise:

(a) does the EES adequately document and assess the nature and extent of the environmental effects of the Project? In addressing this question please explain where you are satisfied with the content of the EES and why, and if not, what if any deficiencies exist in the documentation and/or assessment of the nature and extent of environmental impacts contained in the EES;

(b) can the Project as described in the EES achieve a level of environmental performance which is consistent with relevant legislation, documented and endorsed policy or acknowledged best practice?

(c) if the Project, as described in the EES cannot achieve a level of environmental performance which is consistent with relevant legislation, documented and endorsed policy or acknowledged best practice, are there any recommendations that you would make as to specific measures which you consider necessary and/or appropriate to prevent, mitigate and/or offset adverse environmental effects? If so, please explain your reasoning in detail. To the extent that it is within your expertise to comment upon the feasibility of any of your recommendations, please state whether or not any recommendations are feasible, explaining your reasoning.

(d) how does the Project as described in the EES respond to the principles and objectives of “ecologically sustainable development” as defined in the Ministerial Guidelines for assessment of environmental effects under the Environmental Effects Act 1978 (2006);1

(e) are there any recommendations that you would make as to specific measures which you consider necessary and/or appropriate to improve the response of the Project to the principles and objectives of “ecologically sustainable development”? If so, please explain your reasoning in detail. To the extent that it is within your expertise to comment upon the feasibility of any of your recommendations, please state whether or not any recommendations are feasible, explaining your reasoning; and

(f) to the extent that the content of the draft planning scheme amendment, works approval application or environmental performance requirements (EPRs) lies within your expertise, do you have any recommendations for changes that should be made to the draft planning scheme amendment, works approval or planning approval and/or EPRs in order to improve the environmental outcome of the Project.

5. in due course, review and comment on other parties’ expert evidence in relation to your area of expertise.

6. participate in any expert conclave requested by the IAC;

7. present your evidence at the IAC Hearing. You should anticipate preparing a short (no more than 30 minutes) presentation to facilitate the delivery of your evidence. The presentation is to be drawn from your expert witness report and may respond to other expert reports (as relevant).

Please ensure you are familiar with the requirements of the Planning Panels Guide to expert evidence (DOCX, 81.8 KB), April 2019 and ensure that your evidence is prepared in accordance with the requirements set out in the Guide.

1 At page 5.

https://s3.ap-southeast-2.amazonaws.com/hdp.au.prod.app.vic-engage.files/4515/6107/1277/5._Preliminary_Matters_and_Further_Information_Request.pdf



https://www.planning.vic.gov.au/__data/assets/word_doc/0026/98162/G2-Guide-to-Expert-Evidence-Apr-2019.DOCX

https://www.planning.vic.gov.au/__data/assets/word_doc/0026/98162/G2-Guide-to-Expert-Evidence-Apr-2019.DOCX

[7849160: 24392855_1] page 3

Relevant documents The exhibited EES documents can be accessed at: https://northeastlink.vic.gov.au/environment/environment-effects-statement-ees/environment-effects-statement-documentation. Please also consider any relevant “information updates” contained on the NELP website: https://northeastlink.vic.gov.au/environment/environment-effects-statement-ees/information-updates Please let us know if you require any of these documents in hard copy. We also consider the background information contained in our letter requesting your fee proposal dated 15 April 2019.

Key Dates We are currently waiting on written directions from the IAC to confirm the key dates for the hearing. We will provide these to you when they come to hand. In the meantime, please note the following anticipated key dates:

▪ Your expert witness statement will need to be circulated by 10:00am on Monday 15 July. We kindly ask that you provide us with a copy of the report no later than 5:00pm on Tuesday 9 July.

▪ A conclave of specified fields of experts is likely to be scheduled to occur on the week of 15 July. We will confirm this as soon as possible;

▪ Presentation of the proponent’s case is scheduled to commence on Thursday 25 July; and

▪ Presentation of the Councils’ case is likely to be scheduled to commence in mid-August. We will confirm this as soon as possible.

Key Contacts

The Councils’ representative for this engagement will be Terry Montebello, Partner, Maddocks [email protected] and Phone: 03 9258 3698.

Terry is being assisted by Sophie Jacobs, Senior Associate, Maddocks Phone: 03 9258 3546 Email: [email protected]

Please contact Sophie Jacobs on 03 9258 3546 if you have any queries or wish to discuss any aspect of these instructions with us. Yours faithfully Terry Montebello Partner



https://northeastlink.vic.gov.au/environment/environment-effects-statement-ees/information-updates

mailto:[email protected]

mailto:[email protected]



Expert Witness Statement | Final | 15 July 2019 | Arup

C:\USERS\FRANK.BUTERA\DESKTOP\NELA\EVIDENCE\FRANK BUTERA EVIDENCE NEL.DOCX

Page B1

B1 Response to Scope of Instructions

Paragraph 4

B1.1 Paragraph 4. (a)

B1.1.1 In my opinion Technical Report C and associated Appendices provides an overview of noise and vibration impacts for NEL. Prior to the project commencing additional noise assessments and noise modelling will be required to understand the long-term traffic noise impacts to the existing and future noise sensitive community. Areas that require further attention, include:

• Obtain existing traffic noise levels in accordance with VicRoads

methodology. The existing conditions dataset does not comply

with the methodology approved by VicRoads.

• Calibrate the noise model understanding the existing conditions

which includes a combination of freeways and major roads.

Technical Report C introduces an “alignment” calibration factor

based on the existing noise levels from the Eastern Freeway. It is

unclear of the correlation between the impact of traffic noise to

residential properties from the Eastern Freeway and

• residential properties between the M80 the northern portal and

• residential properties in the vicinity of the M80.

• Develop EPR NV1 to align with VicRoads traffic noise polices.

B1.2 Paragraph 4. (b)

B1.2.1 Technical Report C does not demonstrate compliance with VicRoads traffic noise policies to all noise sensitive receivers impacted by the future alignment. Technical Report C deviates from VicRoads noise policy to introduce at-property noise mitigation solutions.

B1.2.2 Night-time traffic noise limits have been adopted road authorities in New South Wales, Western Australia and South Australia.

B1.3 Paragraph 4. (c)

B1.3.1 Noise impacts from the operation and to some extents construction of the proposed alignment has the potential to adversely impact noise sensitive receivers, due to the following:

• The scale, extent and capacity of the noise source

• The proximity of the noise source to noise sensitive receivers.

B1.3.2 Segments of the alignment are in tunnel, as a result noise impacts to nearby noise sensitive receivers will be minimised and controlled by the tunnel. Other segments are at grade or in-cut, these segments





Page B2

require ongoing noise mitigation infrastructure to be designed and constructed to comply with the project noise limits.

B1.4 Paragraph 4. (d)

B1.4.1 This query falls outside my area of expertise.

B1.5 Paragraph 4. (e)

B1.5.1 This query falls outside my area of expertise.

B1.6 Paragraph 4. (f)

B1.6.1 I have made recommendations to EPR NV1, EPR NV2, EPR NV3, EPR NV4, EPR NV8, EPR NV9 and EPR NV10 in the body of my evidence

Appendix C

Acoustic Terminology





Page C1

C1 Acoustic Terminology

C1.1 Ambient Noise Level

C1.1.1 The ambient noise level is the overall noise level measured at a location from multiple noise sources. When assessing noise from a particular development, the ambient noise level is defined as the remaining noise level in the absence of the specific noise source being investigated. For example, if a fan located on a city building is being investigated, the ambient noise level is the noise level from all other sources without the fan running. This would include sources such as traffic, birds, people talking and other nearby fans on other buildings.

C1.2 Background Noise Level

C1.2.1 The background noise level is the noise level that is generally present at a location at all or most times. Although the background noise may change over the course of a day, over shorter time periods (e.g. 15 minutes) the background noise is almost-constant. Examples of background noise sources include steady traffic (e.g. motorways or arterial roads), constant mechanical or electrical plant and some natural noise sources such as wind, foliage, water and insects.

C1.3 Decibel

C1.3.1 The decibel scale is a logarithmic scale which is used to measure sound and vibration levels. Human hearing is not linear and involves hearing over a large range of sound pressure levels, which would be unwieldy if presented on a linear scale. Therefore a logarithmic scale, the decibel (dB) scale, is used to describe sound levels.

C1.3.2 An increase of approximately 10 dB corresponds to a subjective doubling of the loudness of a noise. The minimum increase or decrease in noise level that can be noticed is typically 2 to 3 dB.

C1.4 dB(A)

C1.4.1 dB(A) denotes a single-number sound pressure level that includes a frequency weighting (“A-weighting”) to reflect the subjective loudness of the sound level.

C1.4.2 The frequency of a sound affects its perceived loudness. Human hearing is less sensitive at low and very high frequencies, and so the A-weighting is used to account for this effect. An A-weighted decibel level is written as dB(A).





Page C2

C1.4.3 Some typical dB(A) levels are shown below.

Sound Pressure Level dB(A) Example

130 Human threshold of pain

120 Jet aircraft take-off at 100 m

110 Chain saw at 1 m

100 Inside nightclub

90 Heavy trucks at 5 m

80 Kerbside of busy street

70 Loud stereo in living room

60 Office or restaurant with people present

50 Domestic fan heater at 1m

40 Living room (without TV, stereo, etc)

30 Background noise in a theatre

20 Remote rural area on still night

10 Acoustic laboratory test chamber

0 Threshold of hearing

C1.5 L90

C1.5.1 The L90 statistical level is often used as the “average minimum” or “background” level of a sound level that varies with time.

C1.5.2 Mathematically, L90 is the sound level exceeded for 90% of the measurement duration. As an example, 45 dB LA90,15min is a sound level of 45 dB(A) or higher for 90% of the 15 minute measurement period.

C1.6 Leq

C1.6.1 The ‘equivalent continuous sound level’, Leq, is used to describe the level of a time-varying sound or vibration measurement.

C1.6.2 Leq is often used as the “average” level for a measurement where the level is fluctuating over time. Mathematically, it is the energy-average level over a period of time (i.e. the constant sound level that contains the same sound energy as the measured level). When the dB(A) weighting is applied, the level is denoted dB LAeq. Often the measurement duration is quoted, thus LAeq,15 min represents the dB(A) weighted energy-average level of a 15 minute measurement.

C1.7 Lmax

C1.7.1 The Lmax statistical level can be used to describe the “absolute maximum” level of a sound or vibration level that varies with time.





Page C3

C1.7.2 Mathematically, Lmax is the highest value recorded during the measurement period. As an example, 94 dB LAmax is a highest value of 94 dB(A) during the measurement period.

C1.7.3 Since Lmax is often caused by an instantaneous event, Lmax levels often vary significantly between measurements.

C1.8 Frequency

C1.8.1 Frequency is the number of cycles per second of a sound or vibration wave. In musical terms, frequency is described as “pitch”. Sounds towards the lower end of the human hearing frequency range are perceived as “bass” or “low-pitched” and sounds with a higher frequency are perceived as “treble” or “high pitched”.

C1.9 Sound Power and Sound Pressure

C1.9.1 The sound power level (Lw) of a source is a measure of the total acoustic power radiated by a source. The sound pressure level (Lp) varies as a function of distance from a source. However, the sound power level is an intrinsic characteristic of a source (analogous to its mass), which is not affected by the environment within which the source is located source is located.