An update to the WHO 2018 Environmental Noise Guidelines exposure response relationships for annoyance from road and railway noise

The systematic review on environmental noise and annoyance commissioned by the World Health Organization (WHO) to inform its 2018 Environmental Noise Guidelines proposed new aggregate exposure response relationships (ERRs) for transportation noise, based on studies published between 2000 and 2014. A subsequent scoping review commissioned by the UK's Interdepartmental Group on Costs and Benefits Noise Subject Group identified 12 new studies for road and nine new studies for rail, published between 2014 and 2019, and recommended that an update to the WHO ERRs may be warranted. This paper proposes updated aggregated ERRs for the percentage of people highly annoyed (%HA) from road and railway traffic noise incorporating data from a subset of recent studies, published between 2014-2022, that met certain eligibility criteria. In light of the ongoing debate on the temporal stability of community annoyance (observed or modelled), we also discuss some of the important considerations that need to be taken into account when deciding if and how often a reference exposure-response relationship is updated for policy and practice.