CAA Policy on Secretary of State Call In for Airspace Change Proposals

The Civil Aviation Authority (Air Navigation) Directions 2017 include one criterion relevant to noise modelling, namely that the proposed change:

could both lead to a change in noise distribution resulting in a 10,000 net increase in the number of people subjected to a noise level of at least 54dB LAeq,16h and have an identified adverse impact on health and quality of life.

This policy clarifies how the CAA will interpret this criterion for the purpose of providing the advice required to the Secretary of State.