Environmental Noise Case Studies
Environmental Noise - Residential
Dragonfly Acoustics was appointed by a construction company to carry out a Noise Impact Assessment for a proposed new development of three dwellings at a site in Goole, Riding of Yorkshire.
The noise assessment was conducted in accordance with Planning and Policy Guidance Note 24 (PPG24). Furthermore, eligibility for planning approval on the grounds of noise was assessed using the guidance given in PPG24.
Dragonfly Acoustics attended the site and undertook noise level monitoring in accordance with the requirements of PPG24 and assessed that the site fell into Noise Exposure Category B for both the daytime and night time periods.
Dragonfly Acoustics then completed an internal noise level assessment, which showed that with their recommended ventilation and glazing scheme the internal noise levels within habitable rooms would meet the required standard of the local authority.
The Noise Impact Assessment showed that when assessed against BS 8233:1999 the Daytime and Night Time internal noise levels were within the “Good” design range and met the “Reasonable Standard” for Night Time maximum noise.
Environmental Noise - Commercial
Dragonfly Acoustics was appointed by a client to carry out a Noise Impact Assessment for a proposed new development at their site near Hull.
The proposed development was a gasification plant and energy generation facility which would produce energy from waste material brought to the site.
Dragonfly Acoustics attended the site and completed environmental noise measurements throughout the night time period to assess the ambient and background noise levels at the nearest noise sensitive property.
The noise survey was conducted in accordance with Planning and Policy Guidance Note 24 (PPG24). Furthermore the assessment made reference to the guidance contained within BS4142 and the IOA/IEMA draft Guidelines for Noise Impact Assessment.
The assessment showed that against the guidance contained in BS4142, the predicted noise levels generated by the gasification plant fell between the categories of “marginal significance” and “complaints unlikely” at the nearest noise-sensitive property during the night time, and fells within “complaints unlikely” during the daytime.
Furthermore when assessed against the IOA/IEMA draft impact scale, the change in ambient noise level between the predicted future and current ambient noise level categorised the change in daytime noise levels as “no change”, and the change in night time noise level as being “barely perceptible” and of “slight significance”.
Therefore it was considered that the change in noise level due to the introduction of the gasification plant would not normally be perceptible.
Environmental Noise – Entertainment and Leisure
Dragonfly Acoustics was appointed to carry out a noise impact assessment for a proposed new external smoking area to a bar and restaurant in Leeds.
Noise measurements were conducted in accordance with British Standard 4142 Method for rating industrial noise affecting mixed residential and industrial areas.
A noise assessment was then undertaken by comparing calculated noise levels with the criteria detailed in British Standard 8233: 1999: Sound insulation and noise reduction for buildings – Code of practice, to assess the potential noise impact on nearby residential properties.
The assessment showed that the predicted internal noise levels due to the use of the proposed smoking area would not meet the “reasonable” internal criterion in accordance with BS8233.
However, it was also shown that, when undertaking the same assessment without the proposed smoking area, the existing internal noise level would similarly not meet the reasonable criteria for internal noise from BS5228.
Therefore a comparison was drawn between the existing and predicted future ambient noise levels. This comparison demonstrated that the ambient noise level would only increase by 2.2dB, an increase which would not normally be perceptible.
Environmental Noise – School and Educational
A contracting company appointed Dragonfly Acoustics to assess the ambient and background noise levels as part of a new development at a college in Kent.
The development comprised the construction of a new building to house additional teaching facilities and refurbishment of the existing buildings at the site.
Dragonfly Acoustics attended the site and conducted a noise survey in accordance with the noise survey requirements as laid out in British Standard 4142:1997 Method for rating industrial noise affecting mixed residential and industrial areas.
This allowed the client to establish if the ambient noise levels incident on the building would meet the requirements of the college, such as those detailed in BB93, and also to establish if the noise performance of new air conditioning plant to be installed as part of the development would meet their planning noise level targets.