Distance from a source and sensitive locations
In this method, the distance of a plan or project from sensitive locations is the measure of health impacts. On a map, fixed-distance contours are drawn around different sources, and the homes, sensitive locations and/or human populations within these contours are shown.
This method is used at the beginning of a planning process, for a quick first comparison of different alternatives in terms of their possible health impacts. The method is suitable for many themes, including for assessing differences in health impacts arising from air pollution and noise nuisance alongside old or new infrastructure. It can also be applied to livestock farming, if data are lacking on environmental burden. The advantage is that it is a simple, rapid method that communicates clearly and requires no exposure data. The latter can also be a disadvantage, as no account is taken of differences in source strength. This method can also be too coarse to enable differences between alternatives to be determined properly.