Noise, Vibration & Air Quality Services LAND AT SPON LANE, GRENDON. Noise & Air Quality Assessment. April AcousticAir Limited

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1 AcousticAir Noise, Vibration & Air Quality Services LAND AT SPON LANE, GRENDON April 2013 Suite 908, 86 Bancroft, Hitchin, Herts SG5 1NQ Tel: Mob:

2 AcousticAir Noise, Vibration & Air Quality Services LAND AT SPON LANE, GRENDON April 2013 Prepared by Dr Michael Forsdyke BSc MSc PhD MIOA for Kler Group Suite 908, 86 Bancroft, Hitchin, Herts SG5 1NQ Tel: Mob:

3 LAND AT SPON LANE, GRENDON Contents Page 1. Introduction 1 2. Noise Standards 2 3. Noise Survey 6 4. Noise Impact Assessment 9 5. Air Quality Standards Air Quality Review Air Quality Assessment Conclusions 24 Figure 1 Figure 2 Illustrative Site Layout Site Location Plan and Noise Monitoring Positions Appendix I Appendix II Appendix III Appendix IV Appendix V Description of Noise Units Noise Measurements Indicative Sound Insulation Performance of Windows Description of Air Pollution Terms and Units Significance Flow Charts

4 1. INTRODUCTION 1.1 AcousticAir have been commissioned by Kler Group to undertake noise and air quality assessments for proposed residential development on land at Spon Lane,. The site is potentially affected by road traffic noise from Watling Street (A5), which runs south of the site but is screened by existing dwellings between the road and the site, and Spon Lane to the northeast, which is only exposed over a small length of the site and also separated from the site by at least 35m. 1.2 During the initial scoping for the site it was considered that there could also be some potential for noise from the operations associated with farm buildings located at the northeast corner of the site, and a small depot located at the southwest. Noise measurements for these locations are included within this report but the current red line application boundary no longer extends as far as these premises, as shown by the illustrative site layout in Figure Section 2 of this report provides details of relevant national guidance on traffic noise, which is the principal source of noise affecting the site. Section 3 presents the results of the noise surveys undertaken for the site, and the assessment of noise on the proposed residential development is considered in Section 4 together with our recommendations for mitigation. 1.4 The scope of the studies for the air quality assessment essentially comprises a review of the Local Planning Authority s (LPA) Air Quality Review and Assessment reports, and appropriate screening modelling of air pollutants with and without development traffic. 1.5 Air quality standards are summarised in Section 5 and a review of the LPA s Air Quality Review and Assessment findings is presented in Section 6. The air quality assessment for the proposed development is presented in Section 7, and overall conclusions for noise and air quality are presented in Section 8. AA790NAQ/R1 1

5 2. NOISE CRITERIA National Planning Policy Framework 2.1 The National Planning Policy Framework (NPPF), issued by the Department for Communities and Local Government in March 2012, sets out the Government s planning policies for England and how these are to be expected to be applied. The NPPF must be taken into account in the preparation of local and neighbourhood plans, and is to be a material consideration in planning decisions. 2.2 With a key emphasis on sustainable development, the NPPF identifies those planning guidance documents that have been revoked and replaced by the Framework, and, in relation to environmental emissions, these include, amongst others, Planning Policy Statement 23: Planning and Pollution Control (2004) and Planning Policy Guidance 24: Planning and Noise (1994). 2.3 The NPPF s new guidance with respect to noise and emissions is that planning policies and decisions should aim to: Avoid noise from giving rise to significant adverse impacts on health and quality of life as a result of new development; Mitigate and reduce to a minimum other adverse impacts on health and quality of life arising from noise from new development, including through the use of conditions; Recognize that development will often create some noise and existing businesses wanting to develop in continuance of their business should not have unreasonable restrictions put on them because of changes in nearby land uses since they were established; and Identify and protect areas of tranquility, which have remained relatively undisturbed by noise and are prized for their recreational and amenity value for this reason. 2.4 In drawing up their Local Plans to implement the NPPF, Local Planning Authorities are advised that significant adverse impacts on any of the three key dimensions of sustainable development (economic, social and environmental) should be avoided and, wherever possible, alternative options which reduce or eliminate such impacts should be pursued. Where adverse impacts are unavoidable, measures to mitigate the impact should be considered, and where adequate mitigation measures are not possible, compensatory measures may be appropriate. 2.5 An important part of the guidance is that planning authorities are advised to focus on (i) whether the development itself is an acceptable use of the land, and (ii) the impact of the use, rather than the control of processes or emissions themselves where these are subject to approval under pollution control regimes. Local planning authorities should assume that these regimes will operate effectively. Equally, where a planning decision has been made on a AA790NAQ/R1 2

6 particular development, the planning issues should not be revisited through the permitting regimes operated by pollution control authorities. Therefore, the NPPF guidance is that where some noise and/or emissions may be present, there are properly adequate forms of legislation, such as the Control of Pollution Act and the Environmental Protection Act etc., that can be readily employed to deal with such matters. 2.6 In addition, for the purposes of decision-taking, policies in existing Local Plans should not be considered out-of-date simply because they were adopted prior to the publication of the Framework. 2.7 Therefore, since existing Local Plans and Council policies may still refer to criteria referred to within earlier planning guidance such as PPG24, these may still be of interest to the decision makers and are summarised below along with other relevant criteria contained within British Standards and other national and international guidance that has not been revoked by the Framework. Road Traffic 2.8 Road traffic noise levels are typically measured and predicted in units of L A10 (18 hour) db in accordance with the Department of Transport s Calculation of Road Traffic Noise, 1988 (CRTN). The L A10 is the A-weighted sound level in decibels exceeded for 10% of the measurement period, which in this case is the 18 hour period between 0600 and 2400 hours. This noise index has been shown to correlate best with people s subjective annoyance due to road traffic noise. L A10 noise levels measured over any three hours between hours are typically 1 db(a) higher than the L A10 over the 18-hour period (CRTN paragraph 43). A fuller description of noise units used in this report is presented in Appendix I. 2.9 With respect to the planning of new residential development in the vicinity of existing road traffic, previous guidance was provided by Planning Policy Guidance PPG24:Planning and Noise. This document provided guidance in terms of Noise Exposure Categories (NEC) for residential development. Four NEC categories were recommended by the PPG as shown below in Table 2.1. For comparison with the L A10 (18 hour) traffic noise index, it is important to note that the PPG noise criteria are in units of L Aeq,T db which is a measure of the total sound energy present in a time period, T, expressed as an equivalent continuous noise level The daytime assessment period used by PPG24 is 16 hours compared to 18 hours used by CRTN. Typically, the PPG s L Aeq,T db noise levels are assumed to be 2 db lower than L A10 (18 hour) noise levels. The PPG criteria are also expressed as free-field noise levels, i.e. away from the reflecting effects of building facades, whereas noise levels predicted at specific buildings by CRTN normally include a facade reflection factor. PPG24 indicates that L A10 (18 hour) noise levels will be higher than equivalent free-field NEC values by a further 3 db(a) due to these reflection effects. Therefore, for any direct comparison between predicted noise levels and NEC criteria, L A10 (18 hour) noise levels will need to be corrected by -2 db(a) in the case of free-field noise AA790NAQ/R1 3

7 measurements or predictions and by -5 db(a) in the case of facade noise levels. Table 2.1: Noise Exposure Categories for New Dwellings near Existing Road Traffic and Mixed Sources. NEC L Aeq,T db ( ) (1) L Aeq,T db ( ) Advice A <55 <45 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 a desirable level. B Noise should be taken into account when determining planning applications and, where appropriate, conditions imposed to ensure an adequate level of protection against noise. 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 >72 >66 Planning permission should normally be refused Note: (1) Sites where individual noise events during the night-time ( ) regularly exceed 82 db L Amax (S time weighting) several times in any hour should be treated as being in NEC C, regardless of the L Aeq,8h (except where the L Aeq,8h already puts the site in NEC D) In the case of night-time noise, the NEC criterion at the boundary of categories A and B is based on a World Health Organisation (WHO) guideline which states that for night-time: based on limited data available, a level of less than 35 db(a) is recommended to preserve the restorative process of sleep. In order to assess internal noise levels, the WHO use a facade insulation level of 15 db (A) where windows are partially open, and PPG24 recommends a reduction of 33 db(a) for closed thermal double-glazing Recent guidance from the World Health Organisation (Community Noise, WHO Vol. 2, Issue 1, 1995, and Guidelines for Community Noise, 2000) is that in order to avoid sleep disturbance the period noise level (L Aeq ) should not exceed 30 db internally. BS 8233:1999 'Sound insulation and noise reduction for buildings - Code of Practice' similarly recommends a good design standard for bedrooms to be 30 db L Aeq or a reasonable standard to be 35 db, and individual noise events should not normally exceed 45 db L Amax as a reasonable internal standard. The BS design criteria for living rooms are 40 db L Aeq as a reasonable standard and 30 db L Aeq as a good standard. AA790NAQ/R1 4

8 2.13 With respect to outdoor noise levels, PPG24 referred to WHO guidance that "general daytime outdoor noise levels of less than 55 db L Aeq are desirable to prevent any significant community annoyance" However, in considering the application of an outdoor criterion of 55 db L Aeq, it is important to take account of the feasibility of achieving such a level. A review of 'Health effect-based noise assessment methods: A review and feasibility study' (NPL Report CMAM 16, 1998) reported the following: "Perhaps the main weaknesses of both WHO-inspired documents is that they fail to consider the practicality of actually being able to achieve any of the stated guideline values. We know from the most recent national survey of noise exposure carried out in England and Wales (Sargent 93) that around 56% of the population are exposed to daytime noise levels exceeding 55 L Aeq and that around 65% are exposed to night-time noise levels exceeding 45 L Aeq (as measured outside the house in each case)... The percentages exposed above the WHO guideline values could not be significantly reduced without drastic action to virtually eliminate road traffic noise and other forms of transportation noise (including public transport) from the vicinity of houses. The social and economic consequences of such action would be likely to be far greater than any environmental advantages of reducing the proportion of the population annoyed by noise. In addition, there is no evidence that anything other than a small minority of the population exposed at such noise levels find them to be particularly onerous in the context of their daily lives." AA790NAQ/R1 5

9 3. NOISE SURVEY 3.1 Ambient noise levels affecting the site during the day and night-time were monitored on Tuesday 12 th and Wednesday 13 th February Road traffic noise levels from the A5 (position 1) and Spon Lane (position 2) were measured in accordance with the shortened measurement procedures of the Calculation of Road Traffic Noise (CRTN) at 50m and 40m respectively from each carriageway edge. The short-term noise survey is endorsed and approved by central government guidance. Indeed, the latest Design Manual for Roads and Bridges (DMRB) provides analysis of data from the National Noise Survey carried out by the Building Research establishment in 2000 and confirms that the CRTN shortened measurement procedure is still a valid method for evaluating the L A10 (18 hour) (Annex A4.41- A4.47, DMRB Vol 11, Section 3, Part 7 HA 213/08). Position 1 was also able to record any noise events associated with the depot area, although the distant road traffic noise from the A5 remained the dominant source. Further sample noise measurements were undertaken adjacent to the farm buildings (position 3). 3.2 Noise levels were recorded using the following equipment, which was calibrated to a reference signal of 94 db immediately prior to and after the survey and exhibited zero drift. CEL envi system hardware and NoiseMaster software; CRL MV 181A Pre-amplifier and cable; MK 224 Precision ½ inch electret condenser microphone; Psion Series 3c organiser to log and display data; Norsonic Type 131 sound level meter; and Larson Davies CA200 acoustic calibrator. 3.3 The microphone was positioned at a height of 1.2 m in a free-field location, i.e. excluding the effect of reflections from buildings or structures. The weather conditions were cold and wet, with easterly winds of up to 3m/s on the Tuesday, cold with no wind over night and cold and wet, with easterly winds of up to 4m/s on the Wednesday. 3.4 During the survey periods the predominant noise for the site was road traffic. There were no noisy operations from the farm buildings during the survey period, and these buildings appear to be used mainly for storage. 3.5 All noise measurements are presented in Appendix II and the traffic noise levels are summarised in Tables 3.1 and 3.2. AA790NAQ/R1 6

10 Table 3.1: Measured Noise Levels at 50m from the A5, db Noise Level, db L A10 3-hour 57.1 Correction for 18-hour L A10-1 Correction for 16-hour L Aeq -2 L Aeq 16-hour 54.1 L Aeq 8-hour (1) 48.7 Note: (1) based either on difference between day and night-time L Aeq measurements or DMRB s quoted 10 db difference, whichever gives the greater noise level. Table 3.2: Measured Noise Levels at 40m from Spon Lane, db Noise Level, db L A10 3-hour 58.5 Correction for 18-hour L A10-1 Correction for 16-hour L Aeq -2 L Aeq 16-hour 55.5 L Aeq 8-hour (1) The noise levels in Tables 3.1 and 3.2 are used within Section 4 of this report to calculate noise levels across the site in order to define noise exposure levels and the need for mitigation. 3.7 There is normally a reduction in traffic flows during the night-time period between hours, which will in turn reduce the noise exposure. Volume 11 Section 3 Part 7 of the Design Manual for Roads and Bridges (DMRB) states that "measurements of noise from roads indicate that on average night-time traffic noise (i.e. noise between 23:00 and 07:00 on the following day) is approximately 10 db(a) less than daytime levels". Adjacent to the A5 and Spon Lane, the measured difference between the day and night L Aeq was only 5.4 db and 8.7 db respectively, therefore, the lesser level differences have been applied to derive the L Aeq (8 hour) at night. The resulting L Aeq (8 hour) are as shown in Tables 3.1 and Adjacent to the A5, analysis of the L Amax noise levels shows that the individual road traffic noise events during the day typically fall well below 70 db. During the night-time measurements, the L Amax noise events similarly lie below 70 db. Therefore, there is no risk of PPG24 s threshold of 82 db L Amax being regularly exceeded by a significant amount at night. For night-time assessment purposes it has been assumed that L Amax noise events due to passing vehicles will typically be 70 db or less at 50m from the A Adjacent to Spon Lane, analysis of the L Amax noise levels shows that the individual road traffic noise events during the day typically fall below 80 db, but with some occasional peaks due to loud vehicles causing peaks between db. During the night-time measurements, the L Amax noise events AA790NAQ/R1 7

11 typically lie below 70 db, with a few events occurring up to 78 db. Therefore, again there is no significant risk of PPG24 s threshold of 82 db L Amax being regularly exceeded by a significant amount at night. For night-time assessment purposes it has been assumed that L Amax noise events due to passing vehicles will typically be 80 db or less at 40m from Spon Lane. The L Amax values are higher at this position due to there being no screening between the site and the road. AA790NAQ/R1 8

12 4. NOISE IMPACT ASSESSMENT Road Traffic Noise 4.1 The noise measurements at the southern end of the site (L Aeq (16 hour) of 54 db and L Aeq (8 hour) of 49 db) equate to the old PPG24 s Noise Exposure Categories (NEC) A during the day and NEC B at night. At the northern end of the site facing Spon Lane, the noise measurements (L Aeq (16 hour) of 56 db and L Aeq (8 hour) of 47 db) equate to NEC B during the day and night. 4.2 Therefore, during the day, apart from a relatively small band facing Spon Lane that falls within NEC B, the majority of the site lies within NEC A. The old PPG guidance for NEC A was that 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 a desirable level. 4.3 At night, more of the site falls within NEC B, and the old guidance for NEC B was that Noise should be taken into account when determining planning applications and, where appropriate, conditions imposed to ensure an adequate level of protection against noise. Therefore, the entire site is suitable for residential development subject to appropriate forms of noise mitigation for those dwellings most exposed to traffic noise. 4.4 The traffic growth over a 15 year design period from 2013 to 2028 would amount to a noise increase of less than 1 db(a) using the traffic growth forecasts provided by CRTN, which would be represented by only a small and insignificant shift in the noise contours across the site. Therefore, essentially the same comments and noise bands relating to the noise measurements in 2013 can be applied to the site to account for future traffic growth by the year The need for mitigation measures for dwellings at the edges of the development that would lie closest to the A5 and Spon Lane are considered below. 4.6 External and internal noise levels have been calculated for indicative dwellings closest to the A5, e.g. at an indicative distance of 50m from the carriageway edge but partly screened by existing dwellings, and the results are presented in Table 4.1. The Table also shows the outdoor-to-indoor level difference (L A ) that windows to habitable rooms must provide in order to achieve BS8233 s reasonable internal noise levels of 40 db L Aeq during the day for living rooms and 35 db L Aeq during the night for bedrooms. The window s required sound reduction index (R) can be calculated from the following equation: Sound reduction index, R = L 1 -L log(S/A) Where, L 1 = façade noise level; AA790NAQ/R1 9

13 L 2 = internal noise level, e.g. noise standard to be met; S = surface area of relevant portion of the building envelope, i.e. the window (m 2 ); and A = absorption in the room (m 2 ). 4.7 For a typical example of window area S = 2 m 2 and room absorption A = 10 m 2, and assuming these factors remain constant over the whole frequency range used for sound reduction purposes, the correction to be added to the level difference L A to derive the sound reduction index R (or R TRA where this is specific to road traffic or other transportation noise) is 7 db. The sound reduction index may also be presented in terms of the weighted sound reduction index R W, which is typically between 3 to 7 (average 5) db higher than R TRA. Therefore, for design purposes, the R TRA will be 7 db lower than the L A, and the R W can be estimated by adding 5 db to the calculated R TRA. Table 4.1: External and Internal Noise Levels Closest to the A5, db Internal Day L Aeq Facade Windows Windows L A closed partly open R TRA Internal Night L Aeq Vent n Garden Facade Windows Windows L A closed partly open Yes Yes Night L Amax Yes Notes: 1. Façade noise level includes +3 db correction for façade reflection effects. 2. Internal noise level with windows closed assumes 33 db(a) reduction for thermal double glazed windows as per PPG Internal noise level with windows partly open assumes 15 db(a) reduction as per WHO guidelines. 4. The minimum required sound level difference L A is derived from the façade noise level minus the internal noise limit, i.e. BS8233 s reasonable noise levels. 5. The minimum required sound reduction index, R TRA is derived from the level difference L A minus The need for ventilation is determined by whether the internal noise level can be met with windows partly open for ventilation. 4.8 For plots close to the A5, Table 4.1 shows that in order to achieve BS8233 s reasonable internal L Aeq noise levels and also the L Amax limit for bedrooms, windows facing the road will need to provide a minimum sound reduction (R TRA ) of no more than 21 db R TRA. Normal thermal double glazing having a configuration of 4/12/4 and 4/16/4, where the information is presented in terms of the thickness of one pane of glass in mm, followed by the size of the air gap, followed by the thickness of the second pane of glass typically provides a sound reduction of 25 db R TRA as indicated by the data in Appendix III, which would more than enable the reasonable internal noise standards to be met. In fact, normal thermal double glazing would also enable the good L Aeq noise standards to be met. R TRA Vent n AA790NAQ/R1 10

14 4.9 Opening windows for ventilation purposes would reduce the insulation provided by the building façade, and internal noise levels would then exceed the design standards, although this situation is not unusual for residential areas within the urban environment where transportation noise is prevalent. In this case, if the Local Planning Authority considers it necessary to satisfy internal noise standards with a degree of ventilation, mitigation measures will be required to enable occupiers to obtain ventilation with windows closed. Passive acoustic ventilators can be installed within the walls of habitable rooms that have windows having an unscreened view towards the A5. These would allow natural ventilation without any loss of amenity due to noise intrusion and would remove the need for 'trickle' vents within the window frames. A number of passive ventilator designs have British Board of Agrément Certification for approval by the Noise Insulation Regulations At a distance of 50m from the A5, and screened by existing dwellings, garden noise levels of 54 db would satisfy the PPG24/WHO criterion of 55 db Dwellings further into the site will experience lower noise levels due to the additional distance attenuation. As a consequence, the internal noise standards for dwellings at the southern fringe of the current planning application, further from the A5 than the Position 1 monitoring location, will equally be achieved using normal thermal double glazing. The additional noise reduction will also be greater than the 2-3 db needed to enable internal L Aeq noise limits to be met with windows open, therefore, no acoustic ventilation would be required Noise levels for dwellings facing Spon Lane would be as shown in Table 4.2. Table 4.2: External and Internal Noise Levels adjacent to Spon Lane, db Internal Day L Aeq Facade Windows Windows L A closed partly open R TRA Internal Night L Aeq Vent n Garden Facade Windows Windows L A closed partly open Yes No Night L Amax Yes R TRA Vent n 4.13 For plots closest to Spon Lane, Table 4.2 shows that in order to achieve BS8233 s reasonable internal L Aeq noise levels, windows facing the road will need to provide a minimum sound reduction (R TRA ) of no more than 12 db R TRA. Once again, normal thermal double glazing would enable both the reasonable and the good internal noise standards to be met However, a higher specification of 29 db R TRA would be required for the few bedrooms facing Spon Lane in order to satisfy the L Amax noise limit aimed at AA790NAQ/R1 11

15 preventing sleep disturbance. This would require a specification similar to 10/12/ The use of passive acoustic ventilators is recommended for living rooms and bedrooms having an unscreened view towards Spon Lane With gardens used for amenity purposes located behind the new dwellings, as shown on the illustrative site layout in Figure 1, outdoor noise levels would be screened from the direct effects of traffic noise and would lie well below the PPG24/WHO criterion of 55 db The noise assessment demonstrates that acceptable external and internal noise levels can be achieved for residents subject to appropriate practicable forms of noise mitigation, although mitigation would only be required for the few dwellings facing Spon Lane along the northwest boundary of the site. This is a matter that can be dealt with by way of planning conditions. For example, conditions can require a scheme for protecting the proposed residential development from road traffic noise to be submitted and approved by the local planning authority, and for all works that form part of the scheme to be completed before any part of the development is occupied. If required, specific noise standards to be achieved inside dwellings can be specified within a planning condition, and these would be attained by way of appropriate window designs. AA790NAQ/R1 12

16 5. AIR QUALITY STANDARDS 5.1 The principal air quality standards applied within the UK are the standards and objectives that were initially formulated within the Air Quality (England) Regulations 2000 (AQR) as amended in These were enacted as part of the UK National Air Quality Strategy (AQS) under Section 80 of the Environment Act 1995, and implement relevant directives of the European Union (EU). The latest version of the UK AQS was published in It is important to note the distinction between standards and objectives. Although the AQS standards define concentration levels that will avoid or minimise risks to health, they do not necessarily reflect levels that are presently technically feasible or economically efficient. In contrast, the AQS objectives have been set with regard to what is realistically achievable within a specified timetable. The approach adopted by the Strategy is to apply the objectives, where members of the public, in a non-occupational capacity and at locations close to ground level, are likely to be exposed over the averaging time of the objective, for example, over 1-hour, 24-hour or annual periods as appropriate. 5.3 Under the Environment Act 1995, Local Authorities must review and document local air quality within their areas by way of a staged appraisal and respond accordingly, with the aim of meeting the air quality objectives by the years defined in the Regulations. Where the objectives of the Regulations are not likely to be achieved by the objective year, an authority is required to designate an Air Quality Management Area (AQMA). For each AQMA the local authority is required to draw up an Air Quality Action Plan (AQAP) to secure improvements in air quality and show how it will try to meet air quality standards in future. 5.4 The Air Quality Strategy is an ongoing mechanism that will be regularly reviewed and updated to take account of evolving European Union (EU) legislation, technical and policy developments and the latest research on health effects of air pollution. 5.5 The Strategy s objectives for particles (PM 10 ), benzene and carbon monoxide were reviewed in 2000/2001 and in February 2003, in the light of more recent scientific knowledge and policy changes, the Government updated the Air Quality Strategy (AQS) by way of an Addendum. The revisions provide alterations or extensions to four of the eight existing pollutant objectives, and the addition of a ninth pollutant, polycyclic aromatic hydrocarbons (PAHs). Further revisions to the objectives were promulgated in the 2007 version of the AQR and the current air quality objectives for the protection of human health are summarised in Table 5.1 below. Definitions of units and terms used to quantify air pollutant concentrations are provided in Appendix IV. AA790NAQ/R1 13

17 Table 5.1: UK Air Quality Objectives for Protection of Human Health Pollutant Concentration Measured as Objective Date Benzene All authorities µg/m 3 Running annual mean 31/12/2003 England and Wales only Scotland and N. Ireland 5 µg/m 3 Annual mean 31/12/ µg/m 3 Running annual mean 31/12/2010 1,3 Butadiene 2.25 µg/m 3 Running annual mean 31/12/2003 Carbon Monoxide England, Wales and N. Ireland 10 mg/m 3 Maximum daily running 8-hour mean 31/12/2003 Scotland only 10 mg/m 3 Running 8-hour mean 31/12/2003 Lead 0.5 µg/m 3 Annual mean 31/12/ µg/m 3 Annual mean 31/12/2008 Nitrogen dioxide 200 µg/m 3 1 hour mean not to be exceeded more than 18 times per year 31/12/ µg/m 3 Annual mean 31/12/2005 Particles (PM 10 gravimetric) All authorities Scotland only 50 µg/m 3 Daily mean not to be exceeded more than 35 times a year 31/12/ µg/m 3 Annual mean 31/12/ µg/m 3 Daily mean not to be exceeded more than 7 times a year 31/12/ µg/m 3 Annual mean 31/12/2010 Particles (PM 2.5 gravimetric) All authorities 25 µg/m 3 (target) 15% cut in urban background exposure Annual mean 2020 Annual mean Scotland only 12 µg/m 3 (limit) Annual mean 2010 Sulphur dioxide 350 µg/m 3 1-hour mean not to be exceeded more than 24 times a year 31/12/2004 AA790NAQ/R1 14

18 125 µg/m 3 24-hour mean not to be exceeded more than 3 times a year 266 µg/m 3 15-minute mean not to be exceeded more than 35 times a year 31/12/ /12/2005 Objectives not yet Prescribed in Regulations for the Purposes of Local Air Quality Management Polycyclic aromatic hydrocarbons 0.25 ng/m 3 Annual mean 31/12/2010 Ozone 100 µg/m 3 mean, not to be exceeded more 8 hourly running or hourly than 10 times a year 31/12/2005 Notes: * how the objectives are to be measured is set out in the UK Air Quality (England) Regulations (2000 and 2002) 5.6 The EU has also set NO 2 objectives for 2010 that must be met by all member states, although these 2010 EU NO 2 objectives are equal to the UK Air Quality Strategy NO objectives. 5.7 Of the pollutants mentioned above, the majority of the UK SO 2 emissions derive from stationary combustion plant rather than traffic emissions. Therefore, this pollutant is not significant for this assessment. Similarly, the concentration of lead in vehicle fuels has been reduced to negligible levels in the past 10 to 15 years, particularly since the introduction of unleaded fuel, and this pollutant is also no longer of concern for this study. Of the remaining pollutants, the standards for carbon monoxide, benzene and 1,3 butadiene are generally met in urban areas. The pollutants of most concern to planning authorities in urban areas, due to the high concentrations presently encountered (of which local road traffic makes a large contribution) are NO 2 and PM 10. London Councils Air Quality and Planning Guidance, January This guidance updates and replaces the Association of London Government s Planning Technical Guidance issued on 20 th March 2001 and Circular TEC 01/03, takes into account new planning policies, including Planning Policy Statement (PPS) 23: Planning and Pollution Control, and aims to help reduce exposure to air pollution across the whole of London. The technical guidance was produced by the APPLE (Air Pollution Planning and the Local Environment) working group and provides useful guidance for assessing the significance of air quality issues at other sites throughout the UK. 5.9 In determining both the significance of exposure to air pollution and the levels of mitigation required, the guidance recommends that consideration should be given to the Air Pollution Exposure Criteria (APEC) as presented in Table 5.2: AA790NAQ/R1 15

19 Table 5.2: Air Pollution Exposure Criteria APEC A APEC B APEC C Applicable Range Nitrogen Dioxide Annual Mean > 5% below national objective Between 5% below or above national objective > 5% above national objective Applicable Range PM 10 Annual Mean: > 5% below national objective 24 hr: > 1-day less than national objective Annual Mean: Between 5% above or below national objective 24 hr: Between 1-day above or below national objective. Annual Mean: > 5% above national objective 24 hr: > 1-day more than national objective. Recommendation No air quality grounds for refusal; however mitigation of any emissions should be considered. May not be sufficient air quality grounds for refusal, however appropriate mitigation must be considered e.g., Maximise distance from pollutant source, proven ventilation systems, parking considerations, winter gardens, internal layout considered and internal pollutant emissions minimised. Refusal on air quality grounds should be anticipated, unless the Local Authority has a specific policy enabling such land use and ensure best endeavours to reduce exposure are incorporated. Worker exposure in commercial/industrial land uses should be considered further. Mitigation measures must be presented with air quality assessment, detailing anticipated outcomes of mitigation measures. Notes: * Applicable ranges assume downward pollutant trend has been established The London Councils guidance also provides a diagram for assisting in determining whether an application is significant in terms of air quality, and the flow chart is reproduced in Appendix V. The matter of significance is AA790NAQ/R1 16

20 based on the professional judgement of the Local Authority officer, and it is advised that even where air quality is deemed not to be a significant consideration, mitigation measures may still be required. Environmental Protection UK (EPUK) - Development Control: Planning for Air Quality, Air Quality Guidance This document updates the guidance originally published by EPUK (formerly known as the National Society for Clean Air and Environmental Protection) in November 2004 (and subsequently revised in September 2006). The 2010 version of this guidance takes account of a number of new documents issued since the previous version, including the 2007 Air Quality Strategy The main focus of the guidance is on the impact of traffic emissions, although increasingly Local Planning Authorities (LPAs) have to deal with the impact of biomass boilers, which is taken into account. The assessment and control of dust impacts during construction is also considered, as dusts contribute to airborne particulate matter, as well as to dust soiling The guidance clarifies when an air quality assessment is required and what it should contain. It sets out how impacts should be described and assessed. Importantly it sets out a recommended approach that can be used to assess the significance of the air quality impacts, taking account of the advice issued by the Institute of Air Quality Management (IAQM). An important focus of this guidance is on minimizing the air quality impacts of all developments for which air quality assessments have been requested by the planning authority; this will be through good design and application of appropriate mitigation measures As with the London Councils guidance, the IAQM guidance likewise relies on the professional judgement of the person preparing the report who must be suitably qualified to do so, and it is open to this person to describe the overall impacts as insignificant, or of minor, moderate or major significance Impact magnitudes and impact descriptors in relation to specific objectives for NO 2 and PM 10 are shown in Tables 5.3 and 5.4. Table 5.3: Definition of Impact Magnitude for changes in Annual Mean NO 2 and PM 10 Concentrations Magnitude of Change Annual Mean Large Increase/decrease >4 µg/m 3 Medium Increase/decrease 2-4 µg/m 3 Small Increase/decrease µg/m 3 Imperceptible Increase/decrease <0.4 µg/m 3 AA790NAQ/R1 17

21 Table 5.4: Definition of Impact Magnitude for changes in number of days with PM 10 Concentrations greater than 50 µg/m 3 Magnitude of Change Number of days above 50 µg/m3 Large Increase/decrease >4 days Medium Increase/decrease 2-4 days Small Increase/decrease 1-2 days Imperceptible Increase/decrease <1 day 5.16 The procedure recommended for LPAs to assess the Significance of Air Quality Impacts associated with proposed developments is summarised in the flow chart show in Appendix VI, which follows a similar pattern to that of the London Councils guidance. Following the assessment of significance, Table 5.5 shows the recommendations that should apply. Table 5.5: Recommendations following the assessment of significance Impact significance from flow chart Overriding consideration High priority consideration Medium and low priority consideration Recommendation Require mitigation measures to remove "overriding" impacts. If the impact is still "overriding", there should be a strong presumption for a recommendation for refusal on air quality grounds. Ensure that measures to minimise high priority impacts are appropriate in the proposal. Recommend strengthening the measures if appropriate. Consideration may also be given to compensation/offsetting. Depending on the scale of the impacts, taking into account the number of people affected, the absolute levels and the magnitude of the changes, and the suitability of the measures to minimise impacts, it may be appropriate to recommend refusal. It is unlikely that refusal would be recommended, but mitigation measures should be incorporated into the scheme design to ensure that the development conforms to best practice standards, and is air quality neutral as far as is reasonably practicable. National Planning Policy Framework 5.17 The National Planning Policy Framework (NPPF), issued by the Department for Communities and Local Government in March 2012, sets out the Government s planning policies for England and how these are to be expected to be applied. The NPPF must be taken into account in the preparation of local and neighbourhood plans, and is to be a material consideration in planning decisions. AA790NAQ/R1 18

22 5.18 With a key emphasis on sustainable development, the NPPF identifies those planning guidance documents that have been revoked and replaced by the Framework, and, in relation to environmental emissions, these include, amongst others, Planning Policy Statement 23: Planning and Pollution Control (2004) With regard to air quality, the NPPF guidance is that planning policies should sustain compliance with and contribute towards EU limit values or national objectives for pollutants, taking into account the presence of Air Quality Management Areas and the cumulative impacts of air quality from individual sites in local areas. Planning decisions should ensure that any new development in Air Quality Management Areas is consistent with the local air quality action plan In drawing up their Local Plans to implement the NPPF, Local Planning Authorities are advised that significant adverse impacts on any of the three key dimensions of sustainable development (economic, social and environmental) should be avoided and, wherever possible, alternative options which reduce or eliminate such impacts should be pursued. Where adverse impacts are unavoidable, measures to mitigate the impact should be considered, and where adequate mitigation measures are not possible, compensatory measures may be appropriate. AA790NAQ/R1 19

23 6. NORTH WARWICKSHIRE BOROUGH COUNCIL AIR QUALITY REVIEW AND ASSESSMENT 6.1 During the first round of review and assessment for air quality in North Warwickshire, a small Air Quality Management Area (AQMA) was identified and declared at a residential property close to the convergence of the M6 and the M42, to the south of Coleshill. 6.2 In the next round, the re-named Updating and Screening Assessment (USA), it was found that there might be exceedences of annual mean benzene objective levels around a large petrol storage and distribution depot in North Warwickshire in This conclusion was based upon the annual throughput of petrol at Kingsbury Oil Terminal and the predicted annual emissions at nearby receptors. 6.3 A detailed assessment was therefore needed to fully assess the impact of benzene emissions from the Oil Terminal. 6.4 The monitoring, modelling and further assessment concluded that the 2010 objective level for benzene would not be exceeded and therefore, there was no need to declare an AQMA in the vicinity of Kingsbury Oil Terminal. 6.5 The AQMA at Coleshill is approximately 14km from the proposed development site at Spon Lane and will therefore, have no impact on, nor be affected by the proposed development. 6.6 Therefore, since there is already relevant exposure at in the form of existing dwellings adjacent to the A5 and Spon Lane, and these have been adjudged by the Council as meeting all air quality objectives, it can be concluded that the site itself equally meets all of the air quality objectives and is acceptable for residential development. AA790NAQ/R1 20

24 7. AIR QUALITY ASSESSMENT Traffic Generated By Development 7.1 Baseline two-way Annual Average Daytime Traffic (AADT) flows for Spon Lane and the A5 have been obtained from the project s traffic engineers (M- EC) and the Department of Transport website ( and are summarised in Table 7.1. The estimated daily contribution due to traffic generated by development is approximately 684 and 181 vehicles/day respectively. Table 7.1: Daily Traffic Flows Road AADT Speed kph %HGV Spon Lane w/o Dev Spon Lane with Dev A5 w/o Dev A5 with Dev Traffic Data 7.2 The traffic data has been used to calculate ambient concentrations of air pollution at an indicative receptor representing existing dwellings adjacent to both Spon Lane and the A5, i.e. at a typical distance of 10m from the centreline of the road, which will reflect worst case receptors close to the road. 7.3 The traffic data has been applied to situations representing a base year in 2013 without and with development, which enables comparison of modelled concentrations with the air quality objectives. 7.4 For determining compliance with air quality objectives, it is important that the contribution of emissions from baseline and with development traffic is added to background concentrations already present in the area; these are defined in the following section. Background Air Quality 7.5 There are no automatic monitoring sites in the immediate vicinity of the development site from which background concentrations can be obtained. Therefore, suitable estimates have been taken from the 2010 update to background concentrations prepared by the National Air Quality Information Archive (NAQIA). Average background pollutant concentrations are available for future years for 1 x 1 km grid squares throughout the Borough. 7.6 Table 7.2 shows the estimated background concentrations that were used in the assessment, as derived from the NAQIA data for the nearest background grid AA790NAQ/R1 21

25 co-ordinate. Background values for NO x are presented, as they are required in the conversion of modelled NO x concentrations to total NO 2. Only those pollutants of real concern to the local authority, namely NO 2 and PM 10, are considered. Table 7.2: Background Concentrations of Air Pollution, Annual Mean µg/m 3 Year NO x µg/m 3 µg/m 3 µg/m 3 NO 2 PM Impact Assessment 7.7 In order to establish whether there is a risk of exceeding air quality objectives adjacent to a road, Local Air Quality Management Technical Guidance (LAQM TG(09)) uses a threshold of 10,000 vehicles/day (vpd) to determine whether further assessment is required. For roads with daily traffic flows below 10,000, there is no risk of air quality objectives being exceeded and the impact from road traffic can be ignored. However, at junctions where the combined flow may be >10,000 vpd the impact should be assessed. 7.8 The AADT baseline traffic flows for Spon Lane (3,193) fall well below the above threshold, and even with traffic generated by development (3,877) the flows lie well below the threshold of 10,000 vpd. Therefore, the LAQM guidance indicates that there is no risk of air quality objectives being exceeded and there is no requirement for further assessment. Nevertheless, an air quality screening assessment has been undertaken and is included below along with that for the A The traffic flows along the A5 exceed the LAQM threshold, therefore, an air quality screening assessment has been undertaken using the methodology defined by the Government s Design Manual for Roads and Bridges (DMRB), which is also the approved screening model (version 2007) under the LAQM guidance. The need for any detailed dispersion modelling is determined from the results of the DMRB screening. The information relating to traffic flows and background concentrations has been input to the DMRB model along with a distance representing the shortest distance between the centreline of roads and dwellings closest to the roads. For assessment purposes a distance of 10m has been used, which will normally be representative of worst case front facades of dwellings facing a road. The results of the DMRB assessment are presented in Table 7.3. AA790NAQ/R1 22

26 Table 7.3: Forecast Concentrations of Air Pollution Situation Year Annual mean µg/m 3 NO x NO 2 1 Annual mean µg/m 3 PM 10 Annual Days >50 mean µg/m 3 µg/m 3 Spon Lane Baseline With Development Change A5 Baseline With Development Change Note: 1 The NO 2 criteria are defined in terms of both the annual mean of 40 µg/m 3, and the number of exceedances of a 1-hour mean of 200 µg/m 3. Whilst the annual mean NO 2 value is calculated, the number of exceedances of the hourly standard cannot be calculated from the annual mean with a high degree of confidence. Therefore, only the annual mean NO 2 value is reported The results indicate that for a 2013 baseline, receptors adjacent to both Spon Lane and the A5 have values below the current annual mean air quality objectives for NO 2 and PM 10, which is consistent with North Warwickshire Borough Council s (NWBC) air quality review and assessments With traffic generated by development, there would be no significant change to the air quality adjacent to either road as the increases due to traffic generated by development would be 0.1 µg/m 3 or less. Annual mean concentrations would lie more than 5% below the national objective, which, using the guidance in Table 5.2, means that the development site would lie within Air Pollution Exposure Category APEC-A for which the guidance is that there are no air quality grounds for refusal Using the flowcharts in Appendix V to assess the significance of the air quality impacts of development similarly results in a conclusion that air quality is not a significant consideration Therefore, since the DMRB screening assessment indicates that current air quality objectives will be met at the most exposed receptor locations, and since the actual changes due to traffic generated by development are small and insignificant, it can be concluded that baseline plus development traffic will not have any adverse impacts on ambient air quality for either the proposed dwellings, or for existing dwellings in the vicinity of the development. Based on the small degree of change due to development traffic, coupled with the fact that no air pollution problems are identified, no further detailed dispersion modelling is warranted since similar impacts would be predicted. AA790NAQ/R1 23

27 8 CONCLUSIONS Noise 8.1 The predominant noise for the site was road traffic using Spon Lane and the more distant and screened A During the day, apart from a relatively small band facing Spon Lane that falls within the old PPG24 s Noise Exposure Category (NEC) B, the majority of the site lies within NEC A. The old PPG guidance for NEC A was that 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 a desirable level. The old guidance for NEC B was that Noise should be taken into account when determining planning applications and, where appropriate, conditions imposed to ensure an adequate level of protection against noise. 8.3 For plots at the southern end of the site closest to the A5, all internal noise standards will be met using normal thermal double glazing having a configuration of 4/12/4 and 4/16/4, where the information is presented in terms of the thickness of one pane of glass in mm, followed by the size of the air gap, followed by the thickness of the second pane of glass. This arrangement typically provides a sound reduction of 25 db R TRA, which would more than enable the good internal noise standards to be met. Reasonable noise standards would continue to be met with windows open for ventilation, therefore, no mitigation measures would be required along this boundary of the site. 8.4 For plots closest to Spon Lane, normal thermal double glazing would again enable both the reasonable and the good internal L Aeq noise standards to be met. However, a higher specification of 29 db R TRA would be required for the few bedrooms facing Spon Lane in order to satisfy the L Amax noise limit aimed at preventing sleep disturbance. This would require a specification similar to 10/12/ For dwellings facing Spon Lane, the noise standards would be exceeded with windows partly open for ventilation, although this situation is not unusual for residential areas within the urban environment where transportation noise is prevalent. If the Local Planning Authority considers it necessary to satisfy internal noise standards with a degree of ventilation, passive acoustic ventilators can be installed within the walls of habitable rooms that have an unscreened towards Spon Lane. These would allow natural ventilation without any loss of amenity due to noise intrusion and would replace the need for 'trickle' vents within the window frames. AA790NAQ/R1 24