CHAPTER 12 NOISE - dppukltd.com · British Standard 5228: 2009 + A1: 2014 12.16 British Standard 5228-1: 2009 ‘ode of practice for noise and vibration control on construction and

CHAPTER 12

NOISE

Environmental Statement – Noise

12-1

12.0 NOISE

Introduction

12.1 This chapter of the ES has been produced by Hoare Lea to assess the Proposed Development in

relation to the effects it would have upon Noise and Vibration.

12.2 In the context of this assessment, noise is defined as unwanted or undesirable sound derived from

sources such as road or air traffic, commerce and construction works that interfere with normal

activities, including conversation, sleep or recreation. Related to noise is vibration, which results

from the transmission of low frequency energy, typically through the medium of ground or

buildings. It results in small movements of the transmitting medium, which can cause discomfort if

the movements are large enough or be re-radiated as noise.

12.3 This chapter of the ES describes the legislative and planning policy of relevance to the Proposed

Development in the context of noise and vibration; the baseline conditions currently existing at the

Site; the methods used to assess the potential impacts arising from the Proposed Development;

and the residual effects following consideration of mitigation measures integral to the design of

the Proposed Development.

12.4 The assessment is based on detailed environmental noise measurements undertaken at the Site

and predictive modelling of the future noise levels.

12.5 In summary, the noise and vibration assessment addresses:

• The potential constraints from existing and potential future sources of noise and vibration on

the external and internal noise environments within the Proposed Development and where

necessary sets out the types of mitigation measures that would be adopted to overcome these

constraints; and

• The Proposed Development's potential impacts and likely effects of noise and vibration on

existing and future sensitive receptors during the demolition and construction works, as well

as from operational noise.

Regulatory and Policy Context

Environmental noise regulations

12.6 The Environmental Noise (Wales) Regulations 2006i as amended by the Environmental Noise

(Wales) (Amendment) Regulations 2009ii aim to define a common approach intended to avoid,

prevent or reduce on a prioritised basis the harmful effects, including annoyance, due to

environmental noise. In this assessment these Regulations are collectively referred to as the

‘Environmental Noise Regulations’.

Planning Policy Wales


12-2

12.7 Current government planning advice to Local Authorities in Wales concerning noise takes two

forms. General guidance is provided by ‘Planning Policy Wales’iii (PPW). Section 6.7 of PPW details

guidance on Air Quality and Soundscape, recognising the association between exposure to air

pollution, which includes noise, and health risks. PPW advises that certain sounds associated with

nature, such as those created by trees, wildlife or water can contribute to a sense of tranquillity

and that problematic forms of sound are generally experienced as noise pollution and can affect

amenity and be prejudicial to health.

12.8 PPW advises that in proposing new development, planning authorities and developers must

address any implication arising because of its location within noise action planning policy areas;

not create areas of inappropriate soundscape; and seek to incorporate measures which reduce

overall exposure to noise pollution and create appropriate soundscapes.

Noise and soundscape action plan 2018-2023

12.9 The noise action plan for Wales sets out the importance of appropriate soundscapes, meaning the

right acoustic environment in the right time and place and that it is not necessarily about the

absolute level of overall noise. Under the Environmental Noise Regulations, the Welsh Ministers

have an obligation to draw up action plans for places near major roads.

Technical Advice Note (Wales) 11: Noise

12.10 PPW is supplemented by ‘Technical Advice Note (Wales) 11: Noise’ (TAN11). The introduction to

TAN11 sets out the importance of appropriately considering noise in planning applications and

states how the planning system can be used to:

‘minimise the adverse impact of noise without placing unreasonable restrictions on development or

adding unduly to the costs and administrative burdens of business.’

12.11 TAN11 defines Noise Exposure Categories (NECs) for proposed residential developments to assist

local planning authorities in their consideration of planning applications near transport related

noise sources. Four NECs are defined in Annex A of TAN11, as summarised in Table 12.1.

Table 12.1: Noise Exposure Categories

NEC Description

A Noise need not be considered as a determining factor in granting planning permission, although the noise level at the high end of the category should not be regarded as desirable.

B Noise should be taken into account when determining planning applications and, where appropriate, conditions imposed to ensure an adequate level of protection.

C Planning permission should not normally be granted. Where it is considered that permission should be given, for example, because there are no alternative quieter sites available, conditions should be imposed to ensure a commensurate level of protection against noise.

D Planning permission should normally be refused.


12-3

12.12 TAN11 also recommends a range of noise levels for each NEC for dwellings exposed to noise from

different transportation sources. The recommended range of noise levels for NECs of proposed

dwellings exposed to road traffic noise have been duplicated below in Table 12.2.

Table 12.2: Recommended Noise Exposure Categories for New Dwellings Exposed to Road Traffic Noise

Noise Levels corresponding to the Noise Exposure Categories for New Dwellings LAeq,T dB

Period A B C D

Day-time 07.00-23.00

<55 55-63 63-72 >72

Night-time 23.00-07.00

<45 45-57 57-66 >66

12.13 In addition to the above equivalent continuous noise levels (LAeq), consideration is also given to the

night-time short-term noise events using the LAmax parameter. For the night-time period TAN11

advises:

‘Sites where individual noise events regularly exceed 82 dB LAmax (S time weighting) several times in

any hour should be treated as being in NEC C, regardless of the LAeq,8H (except where the LAeq,8H

already puts the site in NEC D).’

Supplementary Planning Guidance

12.14 Cardiff City Council has produced Supplementary Planning Guidance (SPG) to provide further detail

on certain policies and proposals contained within Cardiff’s Local Development Plan (LDP).

Approved SPD ‘Planning for Health and Wellbeing’, November 2017, was developed jointly

between the Council and the Cardiff and Vale University Health Board. This SPD places importance

on reducing air, noise and light pollution from development or at proposed development sites.

Reference is made the Local Development Plan Policy EN13.

Local Development Plan

12.15 Cardiff Local Development Plan 2006 – 2026 Adoption Plan, January 2016, (LDP) sets out Cardiff

Council’s framework to bring forward new homes in a managed manner. The LDP includes key and

detailed policies for many aspects of land development, including Environmental. Policy EN13: Air,

Noise, Light Pollution and Land Contamination, aims to ensure the control of these pollutants and

that development are not inappropriately located close to potential sources of this pollution. Policy

EN13 states:

‘Development will not be permitted where it would cause or result in unacceptable harm to health,

local amenity, the character and quality of the countryside, or interests of nature conservation,

landscape or built heritage importance because of air, noise, light pollution or the presence of

unacceptable levels of land contamination.’


12-4

British Standard 5228: 2009 + A1: 2014

12.16 British Standard 5228-1: 2009 ‘Code of practice for noise and vibration control on construction and

open sites - Part 1: noise' (BS 5228-1) provides guidance on a range of considerations relating to

construction noise including the legislative framework, general control measures, example

imethods for estimating construction noise levels and example criteria which may be considered

when assessing the significance of any effects.

British Standard (BS) 8233: 2014

12.17 BS 8233: 1987 is referenced in Tan11 with regard to internal noise levels and has been since

superseded by BS 8233: 2014. This Standard provides guidance for the control of noise in and

around buildings, and suggests appropriate criteria and limits for different situations. The criteria

and limits are primarily intended to guide the design of new or refurbished buildings undergoing a

change of use.

12.18 Table 4 within BS 8233 provides desirable internal ambient noise levels for spaces in residential

dwellings when they are unoccupied. This is reproduced below in Table 12.3.

Table 12.3: Indoor Ambient Noise Levels in Spaces for Dwellings

Activity Location Day-time (07.00 to 23.00)

Night-time (23.00 to 07.00)

Resting Living room 35 dB LAeq, 16hour -

Dining Dining room / area 40 dB LAeq, 16hour -

Sleeping (day-time resting)

Bedroom 35 dB LAeq, 16hour 30 dB LAeq, 8hour

12.19 Supplementary Note 2 and 4 to Table 4 within BS 8233 are copied below for reference:

12.20 ‘NOTE 2 - the levels shown in Table 4 are based on the existing guidelines issued by the WHO…

12.21 NOTE 4 - regular individual noise events (for example, schedule aircraft or passing trains) can cause

sleep disturbance. A guideline value may be set in terms of SEL or LAmax,T depending on the character

and number of events per night.’

12.22 BS 8233 provides recommendations for external noise levels. It recommends that for external

areas used for amenity space, such as gardens and patios, it is desirable that the external noise

levels do not exceed 50 dB LAeq,T, with an upper guideline value of 55 dB LAeq,T being acceptable in

noisier environments.

World Health Organization Guidelines (2000, 2009 and 2018)


12-5

12.23 The World Health Organization (WHO) has published a series of health based guidelines for the

management of environmental noise, to support Member States’ efforts in protecting their

populations’ health from the harmful levels of noise. These are based on a definition of health as a

state complete physical, mental and social well-being and not merely the absence of disease.

12.24 The guidelines are detailed in three separate documents: the WHO ‘Guidelines for Community

Noise’, 2000; the WHO ‘Night Noise Guidelines for Europe’, 2009; and the WHO ‘Environmental

Noise Guidelines for the European Region’, 2018.

12.25 The Guidelines for Community Noise set out the following criteria, shown below, that should be

achieved to avoid sleep disturbance in dwellings.

Table 12.4: Guideline Values for Noise Levels during the Night

Specific Environment Health Effect Guideline Values

LAeq, 8 hour (dB) LAmax, Fast (dB)

Dwelling, inside bedrooms.

Sleep disturbance, night-time

30 45

Dwelling, external noise level, windows open.

Sleep disturbance, night-time

45 60

12.26 The Guidelines for Community Noise also gives the following criteria that relate to noise levels

experienced in outdoor living areas (e.g. gardens).

Table 12.5: Guideline Values for Noise Levels in Outdoor Areas during the Day

Specific Environment Health Effect Guideline Values LAeq, 16 hour (dB)

Outdoor living area Serious annoyance, day-time and evening

55

Moderate annoyance, day-time and evening

50

12.27 The Night Noise Guidelines for Europe provide further criteria that relate external noise levels at

dwellings to specific health impacts. These criteria were produced with the intention of

supplementing the criteria previously published in the ‘Guidelines for Community Noise’. The Night

Noise Guidelines are, however, set in terms of the Lnight, outside, which is the average night time

noise level experienced outside the building over a year. This parameter does not therefore take

into account mitigation measures that may be designed into the building envelope and it requires

knowledge of the noise levels experienced at the development site over the course of a full year.

As such, the Lnight, outside measurement descriptor is not appropriate for assessing the


12-6

acceptability of noise affecting the proposed new development and will, therefore, not be

considered further in this assessment.

12.28 Although the Environmental Noise Guidelines for the European Region supersede the Guidelines

for Community Noise, they do not provide recommendations for indoor noise levels. Therefore,

the indoor guideline values in the Guidelines for Community Noise are considered still valid.

12.29 The recommendations provided in the Environmental Noise Guidelines for the European Region

are given with respect to Lden and Lnight. Therefore, as with the Night Noise Guidelines, these

parameters are not considered valid for assessing the acceptability of noise affecting the Proposed

Development, as they require knowledge of the noise levels experienced at the Proposed

Development Site over the course of a full year and do not consider mitigation measures that may

be designed into the building envelope.

Calculation of Road Traffic Noise (1988)

12.30 In Wales the standard method for predicting road traffic noise levels is given in the Calculation of

Road Traffic Noise 1988 (CRTN). This methodology utilises a number of input parameters (e.g. road

traffic flow, composition, speed, gradient road, road surface, distance of receptor from road etc.)

to enable predictions of noise levels due to road traffic to be produced. This method enables the

calculation of average levels over a period of either 18 hours or 1 hour. Predictions are produced

in terms of LA10, as this is considered the measurement descriptor that best describes road traffic

noise.

Design Manual for Roads and Bridges (2011)

12.31 The Design Manual for Roads and Bridges (DMRB) was originally published by the Department of

Transport in 1993 and sets out procedures for undertaking the design of road schemes. Volume

11, Section 3, Part 7 sets out a methodology for assessing the impacts of noise and vibration. This

methodology can be applied to the assessment of new road schemes or schemes that result in

changes in traffic flows on existing road links. The most recent revision of this section of the Design

Manual for Roads and Bridges was published in November 2011, with a Design Manual Road

Bridges Interim Advice Note (DMRB IAN) published in 2015. The DMRB IAN provides noise speed

bands that are to be used when predicting road traffic noise for motorways and urban/rural roads.

It is therefore this version of the guidance that is referred to in this assessment.

12.32 Table 3.1 of the DMRB, reproduced below in Table 12.6, provides guidance on the magnitude of

short term road traffic noise impacts, such as those that would be experienced due to short term

construction traffic flows. DMRB defines ‘short term’ as when the project is opened, which has

been taken to be the year of opening. Similarly, Table 3.2 of the DMRB, reproduced below in Table

12.7, provides the following criteria relating to long term changes in road traffic noise levels, such

those that could be experienced during the operational phase of the Proposed Development.

DMRB defines ‘long term’ as typically 15 years after the project is opened.


12-7

Table 12.6: Classification of Magnitude of Short-Term Road Traffic Noise Impacts

Noise Change (dB) Magnitude of Impact

0 Negligible

0.1 – 0.9 Low

1.0 – 2.9 Medium

3.0 – 4.9 High

5.0 + Very high

Table 12.7: Classification of Magnitude of Long-Term Road Traffic Noise Impacts

Noise Change (dB) Magnitude of Impact

0 Negligible

0.1 – 2.9 Low

3.0 – 4.9 Medium

5.0 – 9.9 High

10.0 + Very high

Professional Practice Guidance on Planning and Noise - ProPG (2017)

12.33 ProPG Planning & Noise aims to provide practitioners guidance on a recommended approach to

the management of noise in the context of the planning system.

12.34 The document was published jointly by the three professional bodies in the acoustics industry:

Acoustics and Noise Consultants (ANC); the Institute of Acoustics (IOA); and the Chartered Institute

of Environmental Health (CIEH).

12.35 The guide is focussed on new residential development being affected by transport noise. Its

primary goal is to assist in the delivery of sustainable development by promoting good health and

wellbeing through the effective management of noise. It seeks to do this by encouraging good

acoustic design processes in and around proposed new residential development, having particular

regard to national policy on planning and noise.

12.36 The guidance proposes a two-stage approach, including an initial site noise risk assessment (stage

1) and a full assessment and systematic consideration of four elements (stage 2), thereby

encouraging early consideration of noise issues.

12.37 One consideration of the ProPG is that of access to space providing some respite from noise during

those times when homes may be noise affected. This may include at least one façade of a home

being exposed to lower noise levels, thus allowing windows to be opened on that façade for

ventilation purposes in situations where occupants may choose to close windows on a more noise


12-8

exposed façade. Alternatively, where external amenity directly associated with a property is noise

affected, easy access to external amenity space on an acoustically screened side of the property,

or indeed to nearby public open space where the noise levels are lower, may both reasonably be

considered as contributory mitigating factors.

12.38 ProPG additionally highlights the importance of considering noise mitigation as part of a complete

picture of consequential effects. For example, in a particular case the provision of an acoustic

barrier running along the rear garden line to properties may be effective in reducing the exposure

of both the rear gardens and the rear façades of the properties to noise from a specific source

located beyond the acoustic barrier. However, if the acoustic barrier were to take the form of a

solid wood or brick fence or even a landscaped earth bund then, in order to be acoustically

effective, it would necessarily restrict views from both the windows and gardens of the screened

properties. In such cases the appropriate balance needs to be struck between the values of the

view to occupants of the affected houses when compared against the benefits to the same

occupants of reduced exposure to noise.

Scope

12.39 As set out in the Scoping report, the scope of this assessment is to measure the baseline noise

climate experienced across the site and assess its suitability for the proposed use. In addition,

impacts brought about by the change in road traffic noise has been assessed at existing noise-

sensitive receptors. Short-term impacts resulting from the construction of the Proposed

Development have been assessed, including road traffic noise from construction vehicles using the

existing road network.

12.40 The study area includes the development site and nearby noise-sensitive receptors. These include

dwellings immediately north east of the site off Parc-Y-Coed, dwellings to the south east of the site

off Cardiff Road and isolated dwellings to the south off the A4119.

Table 12.8: Representative high sensitivity noise receptors

Receptor ID Property Name / Address

R1 18 Maes Cadwgan, CF15 9TQ

R2 Robin Hill, CF15 9PR

R3 Henstaff Court entrance property, CF72 8NG

Consultation

12.41 Vale of Glamorgan Council were consulted in December 2018 to discuss the approach to the noise

assessment and baseline survey locations. James Holland responded on 07/02/2019 to confirm

some additional information regarding their preferred method, as set out below.

Road traffic noise


12-9

12.42 All habitable rooms exposed to external road traffic noise in excess of 63 dBA Leq 16 hour [free field]

during the day [07.00 to 23.00 hours] or 57 dBA Leq 8 hour [free field] at night [23.00 to 07.00 hours]

shall be subject to sound insulation measures to ensure that all such rooms achieve an internal

noise level of 40 dBA Leq 16 hour during the day and 35 dBA Leq 8 hour at night.

12.43 Suitable active ventilation units are to be provided for habitable rooms that are subject to façade

sound insulation measures.

12.44 50% of any private outdoor living area should not exceed a LAeq, 16 hour day time noise level of 55 dB,

the serious annoyance noise level as defined in the WHO Guideline Values for Noise Levels in

Outdoor Areas during the Day.

Construction site noise

12.45 No noise audible outside the site boundary adjacent to the curtilage of residential property shall

be created by construction activities outside the hours of 0800-1800 hours Mondays to Fridays and

0800 - 1300 hours on Saturdays or at any time on Sunday or public holidays.

12.46 The applicant is also advised to seek approval for any proposed piling operations.

Methodology

Methodology for determination of baseline conditions

12.47 A baseline noise survey was carried out at the site on 14/02/2019 to establish the prevailing

environmental noise conditions. The survey comprised six days of unattended automatic noise

measurements at two locations by separate noise monitors. The position of these monitors is

shown as positions L1 and L2 in Appendix 12.1 Figure 1. In addition, three short-sample

measurements of at least 15 minutes were taken at three further locations shown as A1, A2 and

A3 in Appendix 12.1 Figure 1. All measurements were considered “free-field”, with positions being

approximately 1.5m above ground floor level. Details are provided in Appendix 12.1.

12.48 Measurements recorded consisted of fifteen-minute samples of ambient noise levels (LAeq,15min in

dB), maximum noise levels (LAmax,f in dB) and background noise levels (LA90,15min in dB) between

Thursday 14th February 2019 and Wednesday 20th February 2019. All sound level meters used

during the survey have been laboratory calibrated within two years and were field calibrated with

field calibrator that is within one year of its laboratory calibration. Details of equipment used are

provided in Appendix 12.1. No acoustically important (>0.5 dB(A)) drifts in calibration were found

to have occurred. Systems were set to log the common environmental noise parameters, including

LA10,T and LAeq,T noise levels continuously over the deployment period.

12.49 During the measurement period, temperatures remained cold with some precipitation and winds

varying in both direction and strength. On the 14/02/2019 installation date, little to no wind was

noted, with a dry and overcast morning changing to a clear and bright afternoon.


12-10

12.50 The period of the survey was carefully selected to take place during suitable weather conditions

and when there were no international rugby matches being played at the Principality Stadium,

Cardiff which may have the potential to result in atypical traffic conditions on the M4 motorway.

Methodology for determining operational noise impacts

12.51 The Proposed Development is noise-sensitive, rather than a generator of noise. However,

occupants of new dwellings have the potential to alter the road traffic flow on the existing highway

network. Operational noise impacts are therefore limited to change in road traffic noise.

12.52 The criteria listed in DMRB for assessment of long term road traffic noise impacts have been

adopted for the determination of the magnitude of impact for operational traffic noise as shown

in Table 12.9. This approach is based on the change in road traffic noise level rather than absolute

noise level generated. An increase in noise would be an adverse impact, whereas a reduction in

road traffic noise would be a beneficial impact.

Table 12.9: Magnitude of Operational Traffic Noise Impacts during the Day-time

Magnitude of Impact

Noise Level change, dB LA10, 18hour

Typical criteria descriptors

Very high > 10.0 Change in long term noise level would be perceptible. Considered in DMRB to be a major magnitude.

High ≤ 9.9 > 5.0

Change in level may be perceptible over a long term. Considered in DMRB to be a moderate magnitude.

Medium ≤ 4.9 > 3.0

Change in level may be perceived at the upper end of the range over a long term. Described in DMRB to be a minor magnitude.

Low ≤ 2.9 > 0.1

Small change, would not be perceived over long term. Described in DMRB to be of negligible magnitude.

Negligible < 0.1 No measurable change

12.53 A road traffic noise model has been created using DataKustik CadnaA proprietary noise modelling

software. This software implements the environmental noise propagation prediction methodology

set out in CRTN and is a method for predicting and assessing the impact of noise from a variety of

sources on the existing noise sensitive receptors identified. Several scenarios have been created

in the noise models using road traffic flow data provided by Vectos transport planners, outlined in

Table 12.10 below. Scenario A has been used to compare the measured survey noise levels against

calculated model levels for the current 2018 year, to provide confidence in the noise model. The

noise model scenarios are detailed in Appendix 12.1, Section E.


12-11

Table 12.10: Traffic flow model scenarios

Scenario Traffic flow year

Development flows included?

Description

A 2018 No Current baseline, without development

B 2021 No Future baseline, without development

C 2036 Yes With development, committed (unfettered)

Methodology for determining construction noise impacts

12.54 Full details of the exact construction method, plant and duration is not available at this stage of the

development proposals. The construction noise impact assessment considers the typical activity

based on the type and scale of development. The analysis of likely construction noise has been

undertaken in accordance with BS 5228-1 which provides methods for predicting construction

noise levels based on reference data for the emissions of typical construction plant and activities.

Table 12.11 below shows the assumed construction stages that would take place on site and the

associated sound power levels during these stages. These sound power levels are based on the

likely worst-case scenarios. Assumptions have been made in terms of what plant items will be in

operation and the percentage of time the relevant plant will be in use during a 10-hour period.

Table 12.11: Assumed Construction Work Stage Sound Power Levels

Work Stage Plant / equipment assumed to be in operation Sound power level assumed LWA (dB)

Substructure

360 deg Excavators (Large)

117 Dozer

Impact Piling Rigs

Concrete Pumps

Superstructure

Tower Cranes

111 Concrete Pumps

MEWPS

Goods/passenger hoists

Envelope

Mobile Cranes

106 Tower Cranes

MEWPS

Goods/passenger hoists

Fit-out MEWPS

99 Goods/passenger hoists


12-12

12.55 BS 5228-1 informative Annex E provides example criteria of absolute noise limits for construction

activities and has been used to determine the significance of any construction noise impacts within

this assessment. The criteria do not represent mandatory limits but rather a set of example

approaches intended to reflect the type of methods commonly applied to construction noise. In

broad terms, the example criteria are based on a set of fixed limit values which, if exceeded, may

result in a significant effect unless ambient noise levels are sufficiently high to provide a degree of

masking of construction noise.

12.56 The range of guidance values detailed in BS 5228 Annex E have been used to numerically define

the magnitude levels, as per Table 12.12. The presented impact levels have been normalised to

free-field daytime noise levels occurring over a time period, T, equal to the duration of a working

day on site. BS 5228 Annex E provides varied definitions for the range of daytime working hours

which can be grouped for equal consideration. The values presented in Table 12.12 have been

chosen to relate to daytime hours from 08:00 to 18:00 on weekdays, and 08:00 to 13:00 on

Saturdays. As construction noise will always be an introduction of a noise source which would

otherwise not be there, where impacts are identified to occur they will always be adverse and

never beneficial.

Table 12.12: Magnitude of Construction Site Noise Impacts during the Day-time

Magnitude of Impact

Noise Level, dB LAeq,T


Very high > 82 Trigger level for temporary rehousing, or reasonable cost thereof, as set out in E.4 of BS 5228.

High ≤ 82 > 72

Trigger level for noise insulation works, or cost thereof, as set out in E.4 of BS 5228.

Medium ≤ 72 > 65

Most stringent threshold value for impact given in Annex E of BS 5228 for example methods relevant to Proposed Development.

Low ≤ 65 > 55

Noise is likely to be audible, but unlikely to change behaviour.

Negligible ≤ 55 Below existing noise climate in the surrounding area.

12.57 The construction phase assessment assumes that the residential units associated with the

Proposed Development will not be occupied while construction works serving other phases of the

Proposed Development are being conducted.

12.58 In addition to noise generated within the Site by plant and equipment during the construction

phase of the Proposed Development, changes in road traffic noise has been assessed.

Consideration has been given to revised daily traffic flows as a result of construction vehicles using

the existing highway network to access the site. The magnitude of impact set out in Table 12.13

are based on the short-term impacts given in DMRB and reproduced in Table 12.6.


12-13

Table 12.13: Magnitude of Construction Traffic Noise Impacts during the Day-time

Magnitude of Impact

Noise Level change, dB LA10, 18hour


Very high > 5.0 Change in short term noise level would be perceptible. Considered in DMRB to be a major magnitude.

High ≤ 4.9 > 3.0

Change in level may be perceptible over a short term. Considered in DMRB to be a moderate magnitude.

Medium ≤ 2.9 > 1.0

Change in level may be perceived at the upper end of the range over a short term. Described in DMRB to be a minor magnitude.

Low ≤ 0.9 > 0.1

Small change, would not be perceived over short term. Described in DMRB to be of negligible magnitude.

Negligible < 0.1 No measurable change

Methodology for determining Significant Effect of Operational and Construction Noise Impacts

12.59 Sensitive receptors in the assessment have been classified into the following categories of

sensitivity. These categories have been determined based on the guidance contained in BS 8233,

WHO Guidelines, and other relevant reference criteria. Table 12.14 summarises the sensitivities

for the different receptor types. It should be noted that residential receptors are classed as high

sensitivity, according to the classification system adopted for this assessment and represent those

closest to the Proposed Development.

Table 12.14: Definition of Sensitivity

Sensitivity Typical receptors

Very high Concert hall, recording studios, buildings containing specialist vibration sensitive equipment.

High Residential receptors including residential healthcare and educational facilities (both residential and non-residential).

Medium Non-residential healthcare and hospitals; noise-sensitive leisure receptors e.g. hotels, museums or libraries; places of worship.

Low Commercial facilities e.g. retail or office uses.

Negligible Industrial receptors e.g. workshops or warehouses.

12.60 The significant effect of a predicted impact has been determined through a standard method of

assessment based on professional judgement, considering the sensitivity of the receptor, as set

out in Table 12.14, and the magnitude of impact, as set out in Table 12.9, Table 12.12 and Table

12.13. Table 12.15 provides the significance of effect.


12-14

Table 12.15: Significance of Effect

Sensitivity Magnitude of impact

Very High High Medium Low Negligible

Very high Major Major Moderate Minor Minor

High Major Moderate Minor Minor Negligible

Medium Moderate Minor Minor Negligible Negligible

Low Minor Minor Negligible Negligible Negligible

Negligible Minor Negligible Negligible Negligible Negligible

12.61 ‘Moderate’ and ‘Major’ significant effects are considered as ‘significant’ in the context of the noise

impact assessment for the EIA. ‘Negligible’ and ‘Minor’ significant effects are considered as ‘not

significant’ in the context of the noise impact assessment for the EIA.

Methodology for determining the suitability of the Site for the proposed use

12.62 The level of noise from existing sources near the Proposed Development has been measured during

the baseline noise survey. Future noise levels have been calculated using the noise model scenario

C, design year with existing and development traffic. The noise levels calculated across the Site for

scenario C have been used to assess the suitability of the site for the new and existing dwellings.

12.63 The change in long-term road traffic noise level has been calculated following the methodology set

out in CRTN for the difference between noise modelling scenarios B and C. Changes in long-term

road traffic noise contained within DMRB have been used to classify the magnitude of any impact

from changes in operational road traffic noise.

12.64 The criteria used is the NECs set out in Tan11. Table 12.2 defines the noise exposure category LAeq,T

(dB) levels for new dwellings near existing road traffic noise sources.

12.65 The TRL method three was used to convert the CRTN LA10, 18 hour traffic noise levels calculated in

CadnaA to LAeq, 16 hours and LAeq, 8 hours for daytime and night time periods respectively.

12.66 The models were calibrated against the baseline survey LAeq,T results at unattended measurement

positions L1 and L2, using the scenario A (Baseline 2018) traffic LAeq,T model results at receiver

locations representative of L1 and L2 in the model, set at a relative height of 1.5 meters to the

ground.

12.67 The internal ambient noise limits recommended for new residential dwellings in BS 8233, outlined

in Table 12.3, will be used to assess the internal noise levels. These BS 8233 levels are in accordance

with the internal sound insulation levels specified in the Council’s consultation response.

12.68 External noise levels experienced in amenity spaces, predicted from the 2036 with development

scenario C noise model, are assessed against the WHO guideline limits outlined in Table 12.5.


12-15

Baseline Conditions

12.69 The site is located south of and adjacent to existing residential areas in Creigiau, bounded by Cardiff

road to the east, the A4119 to the south and Tynant Road to the west.

12.70 The ambient noise environment at the relevant noise-sensitive locations was characterised by

traffic noise on the A4119, Cardiff Road as well as distant traffic from the M4 motorway. A nearby

Hensol Corporate Entertainment (HCE) outdoor activity centre which facilitates clay pigeon

shooting was noted, to the east of Cardiff Road and north of the A4119. The outdoor activity centre

was consulted and they confirmed that clay pigeon shooting does not take place at that site and

that this takes place a short distance away. They also confirmed that clay shooting was scheduled

to take place during the survey. From the unattended time history measurement results, no noisy

shooting activity from the centre was evident, implying that this is not of material consideration.

12.71 The results of the unattended measurements at positions L1 and L2 have been calculated into

daytime (LAeq,16hr) and night-time (LAeq,8hr) equivalent levels, and are shown with the instantaneous

measured noise events (LAmax,f). Details of the measurement results are provided in Appendix 12.1

and summarised in Table 12.16 below.

Table 12.16: Measured noise levels (2018)

Location Time period Measured noise levels (dB)

LAeq, T LAFmax, T LA10, 18 hour

L1 Daytime 57 80

58 Night time 51 78

L2 Daytime 56 81

57 Night time 52 80

Assessment without Mitigation

Operational Phase

12.72 Changes in the road traffic flows experienced at existing receptors brought about by the Proposed

Development may introduce a change in the operational noise impact. Table 12.17 below outlines

the predicted changes in traffic noise levels as a consequence of changes in traffic flows from the

proposed development.

Table 12.17: Predicted changes in long term road traffic noise, LA10, 18 hours

Receptor Location

Predicted road traffic noise levels LA10, 18 hour (dB)

Change (C – B) Unfettered 2036 with development (Scenario C)

Future 2021 without development (Scenario B)

R1 55.5 60.3 -4.8


12-16

Receptor Location

Predicted road traffic noise levels LA10, 18 hour (dB)

Change (C – B) Unfettered 2036 with development (Scenario C)

Future 2021 without development (Scenario B)

R2 61.5 61.6 -0.1

R3 60.3 55.4 4.9

12.73 Based on the above, the change in road traffic noise due to the operation of the Proposed

Development would result in magnitude impacts that are of medium beneficial impact at R1,

negligible impact at R2 and a medium adverse impact at R3. The nearby sensitive receptors are

residential dwellings which are considered to have high sensitivity. Taking the greatest adverse

impact from the three considered, a 4.9 dB increase at R3 and with reference to Table 12.15, a

medium impact upon a highly sensitive receptor results in a minor significant effect, which is not

significant in EIA terms.

Construction Phase

12.74 The BS 5228 calculated levels have then been compared against absolute noise limits for temporary

construction activities which are commonly regarded as providing an acceptable level of protection

from the short-term noise levels associated with construction activities.

12.75 To present a simplified worst-case, construction activity has been assumed to all take place at a

single fixed distance from the receiver location. The distance taken is the minimum between the

receptor location and the nearest building proposed within the Site. As the exact distances

involved will vary throughout the construction period this is a worst-case scenario. Consideration

has also been given to a final case with an increased distance of 200 m, to better represent the

typical construction noise level at all receptors when activity is taken place further away. The

assessment results are displayed below in Table 12.18.

Table 12.18: Predicted construction noise levels during the Day-time, LAeq, 10 hours

Receptor Location

Noise levels, LAeq, 10 hour, for corresponding construction phase

Substructure (including impact piling)

Substructure (without impact piling)

Superstructure Envelope Fit-out

R1 73 69 67 62 55

R2 69 65 63 58 51

R3 71 67 65 60 53

200 m 63 59 57 52 45

12.76 The closest residential receptor, R1, is predicted to be exposed to a high magnitude of impact

during the substructure phase of construction if piling is to occur, for the proposed houses closest


12-17

to R1. The high magnitude of impact concluded due to piling, applies only to the initial substructure

phase in the construction timescale for a small quantity of low density proposed housing.

Therefore, this impact is considered short term. However the Council specifies for applicants to

seek approval for any proposed piling activity, therefore no piling activity is expected to occur at

this stage. As R1 is a high sensitivity receptor, assuming no piling activity, a medium magnitude of

impact is concluded. Therefore a minor significance of effect is concluded for the substructure

construction phase at the minimum distance, which is not significant in EIA terms.

12.77 High sensitivity residential receptors R2 and R3 are also exposed to a medium magnitude of impact

during the substructure construction phase of the closest proposed houses. Therefore, for R2 and

R3, a minor significance of effect is concluded as the worst-case scenario. As construction

continues further away from the receptors, the noise level will diminish.

12.78 Noise levels during superstructure and envelope phases of construction predominantly range

between medium and low magnitudes of impact for the closest of works at all three receptors.

The magnitude of impact during fit-out at all three receptors is negligible. Therefore, in balance

the significance of effect during these phases is minor, which is not significant in EIA terms.

12.79 Magnitudes of impact for the typical 200 m construction noise case on the Site are low for all

phases except the fit-out phase, where the magnitude of impact during the fit-out phase is

negligible.

12.80 The 200m assessment concludes a more typical low magnitude of impact during the construction

phase. On balance, the overall magnitude of impact from construction noise levels is medium and

the nearby receptor sensitivities are high. Therefore, the overall effect of construction noise would

be of minor significance effect, which is not significant in EIA terms.

12.81 The above EIA significance classifications apply within the condition that construction activity takes

place only within the hours of 0800-1800 hours Mondays to Fridays, 0800 - 1300 hours on

Saturdays and no construction activity at any time on Sundays or public holidays, as outlined in the

scoping response for noise.

Suitability of the Site for the proposed use

12.82 Tan11 defines four NECs, described in Table 12.1. The CadnaA noise model LAeq, T colour bounds for

scenario’s A, B and C were defined in accordance with the Tan11 NEC LAeq, T dB limits in Table 12.2.

The Site suitability assessment for the proposed development takes the form of noise maps,

indicating areas of the Site possibly requiring noise mitigation measures, based on the traffic flow

data provided. The suitability of the future noise levels across site has been assessed using the

design year, 2036 Proposed Development operational noise model (scenario C). Figure 9 (LAeq, 16 hour

day) and Figure 10 (LAeq, 8 hour night) in the Appendix 12.1, section E illustrate the predicted ambient

noise climate across the site, according to the TAN11 noise exposure categories described in Table

12.1 and defined noise level limits in Table 12.2.


12-18

12.83 Table 12.5 outlines the WHO daytime guideline values for noise levels in outdoor living areas (i.e.

gardens).

12.84 Noise map Figures 9 and 10 in Appendix 12.1 illustrate the TAN 11 noise exposure categories across

the Site. From Figures 9 and 10, much of the site is situated in category A (grey) and if nearby a

road, category B (green), for both day-time and night-time cases. For proposed housing within the

category B region, noise should be taken into account when determining planning applications and,

where appropriate, conditions imposed to ensure an adequate level of protection.

12.85 The noise map displayed in Figure 13 in Appendix 12.1 illustrates the WHO daytime guideline limits

across the 2036 with development scenario. Green areas of the Site indicate a moderate

annoyance (≥ 50 dBA) and blue areas (≥ 55 dBA) indicate a serious annoyance could occur in the

outdoor living areas of the proposed development, according to WHO guidelines. However,

consultation feedback from the Council confirmed all outdoor living areas of the Site, where at

least 50% of the outdoor living areas are below 55 dBA (excepting terraces or balconies to any

apartment), are acceptable. Therefore, in accordance with the consultation feedback, all grey and

green areas of the Site in Figure 13 indicate acceptable predicted outdoor living area noise levels.

12.86 The majority of the proposed development lies within TAN11 noise exposure category A and

proposed housing on the Site boundaries near the A4119 and Cardiff road within category B.

Proposed housing within Category B areas of the Site should take into account noise and where

appropriate, impose conditions to ensure adequate levels of protection.

Proposed Mitigation and Residual Impacts

Operational Phase

12.87 The operational noise impacts from an increase in road traffic would result in no significant effect

at the surrounding noise sensitive receptors. Therefore, no mitigation is required.

Constructional Phase

12.88 The construction noise impacts assessment without piling activity resulted in no significant effect

at the surrounding noise sensitive receptors. Therefore, no mitigation is required. If piling is

required, alternatives to impact-driven piling should be considered. If Hydraulic jacking, water

jetting or continual flight auger methods are used instead of impact piling, then the contribution

from the dominant piling source in the substructure phase may reduce by at least 10 dB.

Mitigation for the Site

12.89 As some of the predicted outdoor living area noise levels are slightly above the WHO upper

guideline of 55 dB, mitigation measures such as careful orientation of gardens and fencing

placement should achieve noise levels less than 55 dB in at least 50% of the outdoor living areas

within the ≥ 55 dB site areas identified on the noise map in Figure 13, Appendix 12.1.


12-19

12.90 For housing within the category B areas of Figures 9 and 10, standard double glazing and ventilation

should achieve the BS 8233 daytime and night time internal levels outlined in Table 12.3, and the

consultation internal noise levels of 40 dBA day and 35 dBA night.

12.91 No specialist acoustic façade treatment is required due to acceptable external noise levels within

noise exposure categories A and B from TAN11 when the windows are closed. Standard double

glazing and ventilation for facades within the NEC category B site areas should achieve the internal

noise levels as defined in BS 8233 (Table 12.3). ProPG suggests that when using windows for

ventilation or cooling purposes, the typical sound reduction across the façade is no more than 10

to 15 dB(A), supported in BS 8233. As windows are unlikely to be open all of the time, an

assumption of 15 dB(A) reduction is considered appropriate given the occasional nature of this

method of ventilation.

12.92 Figure 9 in Appendix 12.1 predicts none of the proposed development facades are to be exposed

to external noise levels in excess of LAeq, 16 hour 63 dB, the external noise limit defined in the

consultation scoping, during the day (07.00 – 23.00). During the night (23.00 – 07.00), Figure 10 in

Appendix 12.1 shows some of the proposed development facades facing onto the A4119 road are

exposed to LAeq, 8 hour noise levels slightly above the 57 dB limit at night. Therefore these facades, in

accordance with the consultation scoping document, require acoustically treated active ventilation

units as an alternate means of ventilation to achieve internal noise levels no greater than 35 dBA

at night. Ventilation specifics detailing how active acoustic ventilation will be implemented in these

facades, can be detailed as the project progresses.

Residual Impacts

12.93 No mitigation has been identified as being necessary for operational or construction noise impacts.

Therefore, the residual impact would remain negligible upon highly sensitive receptors, resulting

in a minor adverse significant effect, which is not significant in EIA terms.

Cumulative Assessment

12.94 The road traffic flow data provided includes all other cumulative developments; therefore,

cumulative noise effects have already been accounted for in the above assessment.

Summary and Conclusion

12.95 An assessment of the potential noise impacts associated with the construction and operation of

the Proposed Development has been carried out.

12.96 The operational noise impacts from an increase in road traffic would result in no significant effect

at the surrounding noise sensitive receptors. Therefore, no mitigation was required.

12.97 Construction noise impacts were found to be generally of minor significant effect with potential

moderate effects on the closest residential receptor R1 to the Proposed Development, which

would be significant in the short term for the nearest new developments in their substructure


12-20

construction phase. However due to the short-term duration of the substructure piling phase,

together with the low-density nature of only a few nearby proposed housing developments, this

was considered to be of minor significance effect overall.

12.98 Assessed against the TAN11 noise exposure category, WHO guideline and BS 8233 standard, the

Site is deemed suitable, providing careful orientation of gardens and fencing placement is

undertaken, to achieve noise levels less than 55 dB in at least 50% of the outdoor living areas,

within the ≥ 55 dB site areas identified in the relevant noise maps. Standard double glazing and

ventilation for facades within the TAN11 category B site areas should achieve the internal noise

levels as defined in BS 8233.

12.99 During the night, some proposed facades exposed to LAeq, 8 hour noise levels ≥ 57 dB at night (Figure

10, Appendix 2.1) closest to and facing onto to the A4119, require acoustically treated active

ventilation units to satisfy the internal noise levels specified in the noise consultation scoping

document.


12-21

Reference List

12.100 British Standard (BS) 8233: 2014

12.101 Welsh Statutory Instruments (2006), ‘The Environmental Noise (Wales) Regulations’.

Environmental Protection, Wales.

12.102 Welsh Statutory Instruments (2009), ‘The Environmental Noise (Wales) (Amendment) Regulations’.

Environmental Protection, Wales.

12.103 Energy Planning and Rural Affairs Welsh Government (2018), ‘Planning Policy Wales, Edition 10’.

The Welsh Government.

12.104 Technical Advice Note (Wales) 11: Noise

12.105 World Health Organization Guidelines (2000, 2009 and 2018)

12.106 Calculation of Road Traffic Noise (1988)

12.107 Design Manual for Roads and Bridges (2011)

12.108 Professional Practice Guidance on Planning and Noise - ProPG (2017)

i Welsh Statutory Instruments (2006), ‘The Environmental Noise (Wales) Regulations’. Environmental Protection, Wales. ii Welsh Statutory Instruments (2009), ‘The Environmental Noise (Wales) (Amendment) Regulations’. Environmental Protection, Wales. iii Energy Planning and Rural Affairs Welsh Government (2018), ‘Planning Policy Wales, Edition 10’. The Welsh Government.

Documents

CHAPTER 12 NOISE - dppukltd.com · British Standard 5228: 2009 + A1: 2014 12.16 British Standard 5228-1: 2009 ‘ode of practice for noise and vibration control on construction and