1. Planning permission for new dwellings and other noise sensitive uses will not be permitted in areas subject to aircraft noise at or above the Significant Observed Adverse Effect Level (SOAEL). Planning permission for new dwellings and other noise sensitive uses in areas subject to aircraft noise between the Lowest Observed Adverse Effect Level (LOAEL) and Significant Observed Adverse Effect Level (SOAEL) will be granted where it can be demonstrated that all reasonable mitigation, through careful planning, layout and acoustic design, has been employed to ensure that the noise impact for users will be acceptable. Applications for sites affected by aircraft noise should be accompanied by a Noise Impact Assessment.

For aviation noise sources, LOAEL is currently considered to be 51dB LAeq,16hr or 45dB LAeq, 8hr. SOAEL is considered to be 63dB LAeq,16hr or 57dB LAeq, 8hr. Regard should be had for both the 16hr and 8hr noise exposure contours when applying the policy. By controlling the type of land uses and the level of noise insulation in development within these areas, the council intends to limit the impact of aircraft noise on residents, workers and other building occupants in accordance with the guidance given by the government under National Planning Practice Guidance for Noise.

Whilst it is possible (given sufficient mitigation) to acoustically insulate the interior of buildings it is difficult to provide any mitigation against aircraft noise in gardens and other outdoor amenity space. To address the introduction of noise sensitive receptors within high aircraft noise contour areas, noise mitigation measures should be designed to achieve BS8233:2014 and World Health Organisation internal and external noise design criteria.

It is recommended that an Acoustic Design Statement be prepared in accordance with ProPG: Planning and Noise, New Residential Development (2017) to demonstrate good acoustic design with a focus on Element 2 – ‘observing internal noise level guidelines.’ If relying on closed windows to meet the internal noise levels, the application would need to demonstrate how an appropriate alternative method of ventilation will be achieved that does not compromise the facade thermal insulation, summertime internal temperatures or the resulting noise level. The council will consider the use of planning conditions or obligations to require the provision of appropriate mitigation measures in the new development.

Leq (Equivalent Continuous Sound Pressure Level) is a measure of the average sound level over a period of time. It represents the constant noise level that would produce the same total sound energy as the varying levels actually measured. LAeq is similar to Leq but includes an A-weighting filter, which adjusts the measurement to reflect the sensitivity of the human ear to different frequencies.