FREQUENTLY ASKED QUESTIONS
Who do we work with?
We provide noise assessments, air quality assessments and lighting assessments for clients across a range of sectors, including industrial, commercial, residential, healthcare and agricultural. Working with designers, developers, planners and architects, we help protect and enhance air quality and the environment to ensure your project is a success.
Which locations do we cover?
We carry out assessments in locations including in the North West, North East and South West including Bolton, Durham and Swindon.
What sectors do we work in?
The main sectors we work across are Residential, Commercial, Industrial, Agricultural, Transport, Healthcare, Sport and Entertainment, and Education.
Acoustics
Sound Insulation - How many tests do I need for my project?
The number of tests required depends on the number of adjacent dwellings, the specific room-to-room adjacencies and the types of construction used.
ADE recommends as a minimum that one set of tests is undertaken for every ten dwellings of the same type and same construction. The number of individual tests in a set of tests varies but is typically no more than 6 tests in total, consisting of:
• Two airborne tests on party floors (one bedroom-to-bedroom, one lounge-to-lounge)
• Two impact tests on party floors (one bedroom-to-bedroom, one lounge-to-lounge)
• Two airborne tests on party walls (one bedroom-to-bedroom, one lounge-to-lounge)
If you send us through your plans, we can work out how many tests you need.
What site conditions are needed for successful testing?
In order to complete sound testing we will need;
• Tests are generally undertaken when a project is close to completion, therefore we require; doors to be fitted, skirting boards and final finishes to be installed. It is not necessary to have completed decorations.
• A 240 volt mains supply, either operational inside or with sufficient extension cable to reach all rooms where testing is being carried out.
• A quiet site, i.e. no site noise or building noises during the period of the tests. Other tradesmen working in the same building and around site can render the test invalid. Problems have been found in the past with, for example; drills, hammering and other impacts, sanding, vacuum cleaners, doors being opened and closed, alarm systems under test, outdoor noises from site vehicles, compressors, pumps, mixers, grinders and saws, and impact noise from paving and gardening equipment.
• The building to be vacated during the tests; the tests are remotely controlled, with sudden bursts of high sound levels which require hearing protection to be worn. This can also startle any other persons within the building who are not involved with the testing.
How are noise assessments undertaken?
Following on from a noise survey, the noise assessment will then involve analysis of the noise data, and predicting future noise levels, often with the use of computer modelling software, to assess the potential noise impacts around the site. The assessment may find the noise levels to be unacceptable and it is then down to the acoustic consultant to recommend specific mitigation measures which would enable recommended noise criteria to be achieved.
How can noise be mitigated?
Noise modelling is an effective tool to demonstrate the effectiveness of various types of noise mitigation measures and can enable them to be assessed and compared. For example, different heights and locations of a noise barrier may be investigated.
Noise mitigation can take various forms, and is often applied as a range of measures within a single scheme. Typical mitigation strategies include the use of acoustic bunds, barriers or fences and alterations to the building layout and orientation.
Noise impacts on a new development may also be effectively reduced by enhancing the specification of the building façade in the form of minimum glazing and ventilation requirements, and enhanced external wall and roof constructions.
Noise impacts from a new development may be effectively reduced by restricting the opening hours and operations at a proposed site so that noise impacts do not occur during sensitive times such as late night and early morning. Noisy equipment may need to be reselected in favour of quieter equipment, or the use of enclosures or silencers may be recommended.
Noise management plans are also an effective means of controlling against potential noise impacts and are sometimes a requirement for certain types of development, such as pubs and clubs.
Which rooms need testing?
It is not necessary to test internal walls and floors within a property. There are also certain limitations on the rooms that may be tested, for example, only habitable rooms are tested e.g. living rooms and bedrooms. Bathrooms do not have to be tested.
Tests are not normally carried out on corridor walls or stairwells although they must be constructed so that they are capable of meeting the ADE performance requirements.
Impact floor tests are not necessary when the room below the floor is commercial rather than residential.
Some Building Control Bodies (BCBs) may also require an airborne test on the party wall between a flat and an existing adjacent property, in which case access will be required to that adjacent property. However, most BCBs accept that it may be difficult to obtain access to a property not owned by the developer, and so will not insist on a test. They will, however, expect to see evidence that the necessary remedial work on the party walls has been undertaken.
Noise Assessments - What kind of developments need a noise assessment?
Developments where noise assessments are needed vary greatly, however as a rule of thumb, if noise levels in an area are relatively high and a development is for housing or other noise sensitive schemes then an assessment will be required. A local Planning Authority can require an assessment as part of a planning submission and will not validate an application without one.
Similarly, where a potentially noisy development is proposed in an area which may impact on an existing residential area or noise sensitive area, such as a hospital or school, then an assessment will be required by the Local Planning Authority. An example of noise impacts coming from a proposed development would be a new delivery yard next to an existing area of housing. In this case, a noise assessment is likely to be required in order to demonstrate that noise from the new HGV deliveries will not cause a significant negative impact at the existing nearby housing, and noise mitigation may be necessary.
What type of noise assessment will I need?
This will depend on the type of development, however almost all sites that need noise assessments will have some sort of noise monitoring carried out. This will involve a qualified acoustic consultant visiting a site, often in the early morning or middle of the night, taking calibrated noise equipment and measuring the existing background sound levels.
Sites with more than one significant noise source will often result in more extensive survey requirements and may mean that more than one form of noise assessment will be required – for example, road noise is typically assessed according to ProPG, BS 8233 and World Health Organisation guidance; noise from industry is typically assessed according to BS 4142 guidance; and noise from construction sites is assessed according to BS 5228 guidance.
Air Quality
What is the difference between a simple air quality assessment and a detailed air quality assessment?
A simple assessment relies on already published information and does not require quantification of impacts. These are usually suitable for smaller developments which are not in air quality management areas. Whereas a detailed assessment is completed with the aid of a predictive technique, such as a dispersion model to quantify that the impacts on or from air quality are acceptable.
When do I need a detailed air quality dispersion modelling assessment?
The Institute of Air Quality Management (IAQM) provides guidance on when an air quality assessment is needed. In general, a detailed air quality assessment is needed if a development may:
- Cause a significant change in traffic flows on roads on which residential houses are located;
- Lead to realigning of roads ie changing the closeness of receptors to traffic lanes
- introduce new road junctions
- introduce or change an existing bus station
- have an underground car park with an extraction or ventilation system
- have one or more substantial combustion processes where there is a risk of impacts at relevant receptors.
For further information have a look at the IAQM Guide or call us.
Can you obtain the air quality traffic data directly from the Transport Assessment/Statement?
No. Air quality assessments are prepared using a traffic data format known as Annual Average Daily Traffic (AADT). This is the 24-hour average of the traffic flow. Usually, Transport Assessment focus on junction capacity assessments and use a measure of AM Peak and PM Peak traffic flows during the daily rush hour periods. AM/PM Peak flows need to be converted to AADT by a transport consultant.
How can we include a good design to reduce the air quality impact i.e delivery of a sustainable development?
There several ways developments can be designed to reduce their impacts on air quality;
- Ensuring that there are large gaps between buildings to allow air to circulate and disperse street level air pollution.
- Minimisation of public exposure by increasing the source to receptor distance, for example, increase the width of pavements or increase the stack heights of chimneys.
- Providing charging points for electrical vehicle
- Providing cycle paths which link to local cycling networks, secure bike storage facilities and lighting to support sustainable transport
- Sustainable Travel Plans
- Provide low emission heating within the development.
Why do you need to complete three odour sniff tests?
Odour generation and dispersion are never constant. The strength of the odour and the potential for it to disperse is influenced by a multitude of factors, such as the weather conditions and the odour source activities. The purpose of sniff testing is to establish the odour pattern and to advise whether the odour observed is significant, or not significant at the development site. To ensure a robust conclusion reached a suitable number of sampling visits is needed across different conditions and situations to account for the variation of the odour being surveyed. Three sniff tests on separate days is the recommended number stated in the Institute of Air Quality Management ‘Guidance on the Assessment of Odour for Planning’ 2018.
Contact Miller Goodall to talk about your requirements or request a quote.
Bringing Miller Goodall into your project as environmental consultants means you can be certain that you are meeting the required standards of environmental best practice. Talk to us: info@millergoodall.co.uk
