About our services in surveying and analysing noise
MAS Environmental Ltd have qualified acousticians and environmental health experts based in Cambridge and Nottingham.
We conduct noise surveys nationwide and this sometimes involves leaving equipment on site to measure for longer periods to gain a better understanding of the noise environment.
What is a noise survey?
Noise surveys typically involve the use of sophisticated sound measuring equipment (including type 1 sound level meters, external environmental microphones and low noise microphones) to describe the sound environment of an area. There are many different types of noise surveys which aim to assess different aspects of our sound environment. Some of the main types of noise surveys that MAS undertake are detailed below.
Occupational noise survey / risk assessment
The Control of Noise at Work Regulations apply to all industry sectors in Great Britain. The aim of an occupational noise survey is to assess the amount of noise or sound to which employees are exposed whilst in the work place. The primary focus is the protection of hearing, though there are many other benefits to assessing the sound environment of the workplace. If an employee is exposed to a typical daily or weekly noise level that exceeds 80dB(A), an occupational noise survey and risk assessment must be undertaken to comply with the Regulations. If typical daily or weekly noise levels exceed 85dB(A), hearing protection must be provided to employees and other important factors must be considered, for example health screening and hearing tests.
In order to conduct an occupational noise survey MAS representatives would visit the workplace to review the current provisions in place to protect hearing and safety from excess noise and measure the levels of noise to which employees are typically exposed. A formal report is provided, including any recommendations, which demonstrates that noise has been identified and assessed in compliance with the Regulations.
Background noise survey
Background noise surveys measure the day to day variations in sound level in an area. Background noise surveys are often required for planning applications and by local authorities in order to ensure that either a new development will not generate unreasonable levels of noise or be adversely impacted by existing levels of noise in the area.
Whilst background noise can be assessed by several spot measurements (short attended periods) MAS often recommend leaving equipment for a longer period of several days. This allows a detailed review of the sound environment including diurnal variations and features of the sound environment, for example the dawn chorus or temporary noise from boiler flues, that might otherwise be missed.
Noise impact assessment / BS4142 assessments
A noise impact assessment is a more detailed noise survey that expands from that of a more basic background noise survey. These are often required for planning applications and are requested by local authorities in order to establish the environmental impact of a development. A noise impact assessment will typically involve an assessment of the background noise environment and comparison of this to either the measurement or prediction of the noise level generated by the proposed development. In the case of proposed housing development the impact of existing noise sources will need to be assessed to ensure that an acceptable internal and external dwelling environment can be created without unreasonable burdens being placed on other nearby noise generators. A noise impact assessment might also be taken in order to measure the status quo. Sometimes industry is required to keep a check on the level of noise they emit to ensure compliance with any imposed noise conditions and / or to demonstrate good neighbourliness.
Noise nuisance survey and expert witness services
Noise is commonly defined as unwanted sound. Noise can disturb people in many different ways. A noise does not have to be loud to be intrusive and many different aspects, such noise character, can influence how a noise is perceived. If a complaint has been made about a noise, a survey would be undertaken in order to measure the noise. This would involve evaluating the decibel level of the noise, spectral content of the noise (pitch), background noise level in the absence of the noise etc. Whether a noise is considered a nuisance takes account of these factors but also considers frequency and duration of the noise, the character of the area, time of occurrence. The objective noise levels can be compared to noise guidance (where applicable) and combined with observations of noise impact to determine whether a statutory or common law nuisance exists. MAS have acted as expert witnesses in a number of cases including planning hearings, planning inquiries and instructed in a variety of court cases including the High Court.
Other noise surveys
There are many other types of noise surveys that can be undertaken and MAS are happy to tailor surveys for specific needs. For example, entertainment venues often install noise limiters to ensure that excess noise generated within a venue does not cause adverse impact to neighbours. MAS can assist by conducting a simple noise survey that tests the levels generated in the venue with the noise limiter and simultaneously assess impact in the community. This allows a fixed noise level to be set in the venue that results in acceptable levels in the community.