The European Regional Office of the World Health Organization (WHO, 2018) recently dramatically lowered its former (WHO, 2000) recommendations for cumulative aircraft noise exposure levels associated with risks of adverse public health effects. WHO's recommendations, although lacking the force of law, are nonetheless of interest to aviation regulatory bodies and to the public at large. It is therefore important that WHO's recent recommendations receive and withstand careful scrutiny. WHO's (2018) recommendations are based on controversial assumptions, analyses and interpretations prepared by Guski et al. (2017). Gjestland (2018) identified a number of limitations of the opinions expressed by Guski et al. (2017). Guski et al. (2019) subsequently challenged some of Gjestland's (2018) observations. This paper responds to the defenses offered by Guski et al. (2019) of the opinions expressed in their prior (2017) publication.
Keywords: WHO recommendations; aircraft noise; annoyance.