Noise Assessment Report Callow's Yard

TO: 01925 723333 AO acoustic design & control

PO Box 1030 Warrington Cheshire WA4 9FJ

Fax: 0645 833 0989

ARR/APF/C/1677.01

30th June 2009 Rev 8th September 2009

Callow's Yard

Assessment of Noise Related Planning Issues at Callow's Yard, Malew Street, Castleton, Isle of Man.

Prepared for: Callow's Yard Lorne House Castleton IM9 1AZ

Prepared by: Andrew Raymond

AO acoustic design & control limited

registered office: 1210 centre park square warrington cheshire wa1 1ru registered in england no. 5117653

Contents

1.0 Summary

2.0 Introduction

3.0 Assessment Standards

3.1 BS8233 3.2 Extracts from Noise from Pubs \& Clubs 3.3 Local Authority Criteria

4.0 Survey Details

4.1 Site Times and Personnel 4.2 Instrumentation 4.3 Measurement Positions 4.4 Survey Conditions

5.0 External Noise Break-In

5.1 Basic Results 5.2 BS8233 Assessment

6.0 Noise From The Bar Lounge And Function Room

6.1 Noise from the Bar Lounge 6.2 Noise from the Function Room 6.3 Possible Conditions

7.0 Mechanical Services Noise

7.1 Overview 7.2 Possible Conditions

8.0 Conclusions/Recommendations

Appendix 1: Definition of Acoustic Terms Appendix 2: Calculation Details

1.0 Summary

In terms of the existing external noise, the site is entirely suitable for residential accommodation of all types.

In terms of the impact the site will have on the existing residential accommodation and the residential accommodation of the new site, the most likely potential sources of noise are the function room, the bar lounge, the food retail extraction systems and the air conditioning.

The function room will require controls on music. The function room should be fitted with a properly designed and commissioned sound system with noise limiter. In order to operate to music noise limits while still delivering suitable music levels within it for functions, windows and sky lights will need up grading. The developer could of course opt to operate at lower levels without the window and skylight upgrades. The bar is not intended for anything other than background music, probably just a piano, and so should not be a problem.

Simple noise control should be straight forward enough to control noise from the mechanical equipment associated with the food retail. The air conditioning units should not cause any problems.

A R Raymond

P J Durell

2.0 Introduction

Environment Experiencing the Noise	Criterion	Implied Limits
		LAeq (9703-2336)	LAeq (2360-0700)	LAmax (2366-0700)
Living Rooms	Good Conditions	30dB	n/a	n/a
Reasonable Conditions	40dB	n/a	n/a
Bedrooms	Good Conditions	n/a	30dB	45dB
Reasonable Conditions	n/a	35dB	45dB

ADC was asked to carry out an independent assessment of the noise related planning issues of the above development.

The issues of potential concern were discussed on two occasions with Mr Simon Renton of the local EPU. In our first meeting the issues of concern were identified as the marquee (which is no longer part of the scheme), the function room and the food retail mechanical services. In a subsequent telephone conversation, the bar lunge lounge and function room ventilation were discussed along with the original items, as well as the fact that the marquee has been dispensed with. The proposals of this report were all agreed in outline.

This report begins by summarising assessment standards and, where appropriate, discusses alternative interpretations.

After a brief statement of survey details we discuss basic survey results and the resulting assessment of existing external noise, the potential impact of the bar and function room, and the impact of mechanical plant, we discuss any mitigation and possible planning conditions which might be implied. We sum-up and conclude at the end, along with brief recommendations.

One potentially complicating issue is that the planning issues are in some ways retrospective in that the site is well under way and in fact close to completion. The advantage of this is that sources such as the food extraction can be measured directly rather than theoretically.

3.0 Assessment Standards

There are several standards which need to be considered. All need to be viewed, and adjusted if necessary, to the situation at hand.

3.1 Bs8233

BS8233 is a wide-ranging document which covers many aspects of noise in buildings but includes recommended "Reasonable" and "Good" noise climates in its Table 5. Of most significance to environmental noise assessments are the levels given for living rooms and bedrooms.

The significant aspects are summarised below:

Note that the standard accepts the widely used rule of thumb that, for a partly open window, the levels just outside will be 15dB higher than

those just inside. This brings us to an external equivalent of the above table, as follows:-

Note also that the standard is aimed at general anonymous noise and not necessarily specific and identifiable sources. In a rural situation this might be distant traffic interspersed with infrequent local traffic. In a suburban situation this might be local and middle distance traffic. In a city centre, this might be crowds of people and busy traffic, and perhaps some faint music.

Most acoustics professionals have some difficulties with BS8233 or with the way it is often interpreted. Firstly, it is design guidance. It is not a set of rigid criteria, below which a development “passes” and above which a development “fails”. For instance, with windows open, there can be very few developments outside the quietest of areas where the internal levels do not exceed the various “good” criteria. Also, there is the issue that the L_Amax criteria for night time are the same for “good” and “reasonable” conditions. It is not clear why this is so, many argue that it has no relevance in many areas, especially a city centre and that an internal level of 50 dB L_Amax would be more than reasonable.

3.2 Criteria – Music Noise affecting existing Residential

This is a complicated section with lots of jargon and terminology. It is not intended for the lay reader, but for local authority officers with some expertise in acoustics. It is mainly aimed at the potential impact of the marquee when it may be used for potentially noisy activities involving music, and for the function a hall.

Noise from Pubs and Clubs

One useful document is Noise from Pubs and Clubs (Davies et al, 2005) which itself devotes a large part of its content to reviewing criteria and standards. Some of the most widely used are discussed in the following paragraphs.

The document refers to the Code of Practice on Environmental Noise Control at Concerts, issued by the Noise Council (1995). The night-time criterion is that between 2300 and 0900, music should not be audible in any noise-sensitive room with an open window, although it does not attempt to define a measure of inaudibility. At other times, absolute criteria are stipulated according to the number and category of event. These criteria are in terms of 15-minute L_Aeq levels at 1 m from the noise-sensitive façade. See following table and Definitions of Acoustic Terms in Appendix 1.

5

Environment Experiencing the Noise	Criterion	Implied Limits
		LAeq (0700-2300)	LAeq (2300-0700)	LAmax (2300-0700)
Living Rooms	Good Conditions	45dB	n/a	n/a
Reasonable Conditions	55dB	n/a	n/a
Bedrooms	Good Conditions	n/a	45dB	60dB
Reasonable Conditions	n/a	50dB	60dB

MNL (Music Noise Level) is the of the music measured at 1m from the façade between 0800 and 2300 hrs. Table 1. Outdoor event noise limits in the Noise Council Code of Practice

In 1996 a group drawn from a wide range of stakeholders (enforcement and licensing authorities, pubs and clubs industry, consultants, etc) began a study but disbanded before definitive conclusions were drawn. The only output was the Good Practice Guide (Institute of Acoustics, 2003). The annex containing the proposed criteria was as follows:-

Concert days per year, per venue	Venue Category	Guidelines
1 – 3	Urban Stadia/arenas	MNL should not exceed 75dB(A) over a 15 minute period
1 – 3	Other Urban/rural venues	MNL should not exceed 65dB(A) over a 15 minute period
4 – 12	All venues	MNL should not exceed LA90 by more than 15dB over a 15 minute period

EN = Entertainment noise level. WEN = Representative background noise level without the entertainment noise, both measured 1m from the façade of the noise-sensitive premises.

• Not more than once a week and ends by 2300hrs.

Table 2. Limits suggested in the IOA Annex

Examples of other standards used, for instance by local authorities, are also sited in Noise from Pubs and Clubs, are as follows:-

Sheffield City Council:

Entertainment noise should not exceed the following:

Bedrooms Noise Rating Curve NR25 (2300 to 0700 hours)<br/> Living Rooms Noise Rating Curve NR35 (0700 to 2300 hours)

See definitions of Acoustic Terms in Appendix 1. The advantage of using NR criteria is that they are not dependant on background noise which is variable with location, time of day, day of week, time of year, etc. However, NR curves were not designed for this purpose.

Venue Where...	Suggested Regulations	Outcome if Criteria Met
Entertainment < 30 times/year*	LA90,15mins (EN) should not exceed LA90 (WEN) by more than 5dB.	EN will generally be audible but not overly obtrusive inside the noise sensitive property
Entertainment > 30 times/year*	LA90 (EN) should not exceed LA90 (WEN) by more than 5dB And the L10 (EN) should not exceed L90 (WEN) by more than 5dB in any 1/3 octave band between 40 and 160Hz.	EN will generally be audible but not overly obtrusive inside the noise sensitive property
Entertainment > once/week or continues beyond 2300hrs	LA90 (EN) should not exceed LA90 (WEN) And L10 (EN) should not exceed L90 (WEN) in any 1/3 octave band between 40 and 160Hz.	EN will be virtually inaudible inside noise sensitive property.

Kirklees MBC:

Zero increase in the LAeq, (music playing) over the background LA90 (music off)

and

Zero increase in the L10 vs. L90 exceedance in each 1/3 octave band between 40Hz and 160 Hz.

These figures apply within a bedroom and equate to exceedances of 5 dB outside an open window.

These are very similar to our own definition of inaudibility, based on our own investigations, although we prefer to use Leq in the 63 Hz and 125 1/1 octave bands as it is far easier to measure and therefore enforce. The L10 levels should rarely exceed the Leq levels by as much as 5 dB. So, an exceedance of 0dB (L10 vs. L90) within a room with an open window should be reasonably represented by an exceedance of 0dB (Leq vs. L90) at 1m from a façade.

London Borough of Camden:

3dB increase in the LAeq, (music playing) over the background LAeq (music off)

and

Zero increase in the Leq vs. Leq exceedance the 63 Hz 1/1 octave band.

and

Inaudible between 23:00 and 07:00. Note that they do not attempt to define inaudible. Again criteria apply inside habitable rooms. Our summary of Recommended Criteria

For up to 12 events per year, we would suggest the criteria from the Code of Practice on Environmental Noise Control at Concerts. Above this, we suggest that a combination of the annex to the IOA Good Practice Guide and the local authority criteria cited in Noise from Pubs and Clubs, modified for practicalities as discussed.

Our recommended criteria are as follows:-

1. For up to 3 events per year between 07:00 and 23:00 hours:

Music noise levels should not exceed 65 dB LAeq,15min at 1m from the façade of any noise sensitive room.

1. For between 4 and 12 events per year between 07:00 and 23:00 hours:

Music noise levels measured in terms of LAeq.15min at 1m from the façade of any noise sensitive room should not exceed the background noise levels (ie. without music playing) measured in terms of LA90 by more than 15 dB.

1. For between 13 and 30 events per year between 07:00 and 23:00 hours:

Music noise levels measured in terms of LAeq.15min at 1m from the façade of any noise sensitive room should not exceed the background noise levels (ie. without music playing) measured in terms of LA90 by more than 5 dB.

In addition music noise levels measured in the same way as above in the 63 Hz and 125Hz octave bands should not exceed the background noise levels also as measured above by more than 5 dB in respective octave bands.

1. For more than 30 events per year and at times between 23:00 and 07:00 hours:

Music noise levels measured in terms of LAeq.15min at 1m from the façade of any noise sensitive room should not exceed the background noise levels (ie. without music playing) measured in terms of LA90.

In addition music noise levels measured in the same way as above in the 63 Hz and 125Hz octave bands should not exceed the background noise levels also as measured above in respective octave bands.

Of course you may choose to simplify things. If, for instance, you know you are likely to exceed 12 events per year, then the first two can be dispensed with.

3.3 Local Authority Criteria

At a site meeting with Mr Simon Renton in June, the basic criteria agreed for the houses and apartments within the development affected by the noise generated by the development were based on BS8233 criteria.

It is the case that the same management would be in control of both accommodation and site activities and so noise problems would be unlikely to reach the EPU in the form of complaints.

The main concern would therefore be the surrounding existing residential accommodation, the criteria for which are covered above.