The problem arises because many claim properties lie 500 metres or more from the new road, and at such distances received A-weighted traffic noise levels can vary by 15dB or more, due to meteorological effects alone. Much effort has been expended on establishing the dependence of received noise levels at large distances from roads on specific meteorological parameters. The ultimate objective of this work is to provide a consistent and defendable approach to establishing noise levels in respect of compensation claims. A number of other environmental noise problems have been investigated. These most often concern industrial noise affecting residential areas at night.
Vibration also continues to be a problem, in particular in the community.
Disturbance due to equipment operating in commercial premises under apartments has been investigated, and dynamic tests have been carried out in a new multi-storey hotel. Modal response data was acquired to assess whether activity in the public area would cause disturbance in bedrooms. The main activity in the area of computational acoustics has continued to centre on two research projects associated with the drive to reduce noise pollution around airports. These major long-term contracts are administered through the ISVR and carried out by ICS staff seconded to the Department. This is now a significant noise source for aircraft on approach.