Developing a credible odour monitoring program

In communities around the world odour issues are addressed in a variety of ways. Often odour regulations place a limit on the strength of ambient odour. The strength of odour in the ambient air is measurable using either an n-butanol intensity referencing scale or a field olfactometer. These standard methods can be utilized by facility personnel to conduct proactive odour monitoring as well as for responding to odour complaints. A credible odour monitoring program must begin with proper training of odour observers/inspectors. Training must prepare the investigator to make observations using standard procedures and to record pertinent information in a standard, clear format. The trained odour investigator must also be provided with an understanding of how to prepare and present the investigative reports to supervisors, facility managers, and officials. This paper will discuss the following topics: 1) elements of an odour inspector training program, 2) odour observer/inspector sensitivity testing, 3) elements of an odour monitoring plan, and 4) standard methods and procedures for quantifying ambient odours. This paper will present and discuss case studies of odour monitoring programs in the U.S. and Canada, including benefits of the monitoring program in each specific case.