The Review of the Odour Legislation

Odours are often the most significant contributor to air pollution complaints. Many countries have incorporated odour emissions into their environmental legislation during the past few decades and as a result continue to upgrade this legislation. There are many sources of odour emissions including industrial, municipal and agricultural sectors.Odours have always been discharged from all types of agricultural operations but this sector is becoming increasingly important because of the growing number of concentrated animal feeding operations and, in many countries, the advancement of housing developments into rural areas. Hence, there appears to be a need for continued development of odour legislation for this sector and, because of national priorities to protect agriculture and the nature of these operations, this legislation may be quite different from other sectors.Legislation covering most types of air pollutants, such as dust, metals, acid gases, volatile organic compounds and semi-volatile organic compounds tend to be fairly consistent in those jurisdictions which have such legislation. Odour legislation, however, tends to be much more varied and ranges from no specific mention in environmental legislation to extensive details which include odour source testing, odour dispersion modeling, ambient odour monitoring, setback distances, process operations and odour control procedures.This paper covers the three approaches to legislate environmental odours including a qualitative approach in which odour is regarded and assessed as a nuisance, quantitative in which odour standards are provided for assessing odour data obtained form ambient air measurements or odour concentrations predicted from a combination of source odour testing and atmospheric dispersion modeling and operational requirements which may include setback distances, specific operating procedures and specific odour control equipment.This paper summarizes the legislations in Canada, United States, Australia, New Zealand, Europe and Asia.