Dynamic olfactometer

Detection threshold (DT)

Detection threshold is essentially the minimum amount of odorant that can be perceived (smelled).  This minimum amount represents the odour concentration and is a measurement of 1 OU (1 odour…

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Dynamic dilution

Mixing of odourous gas and odour-neutral air measured by flow rate. The consistent introduction of odour-free or odour-neutral air to a concentrated amount of an odourous gas allows for an…

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Dynamic Dilution Olfactometry

Dynamic Dilution Olfactometry  is based on “dilution to threshold” of a gas sample with multiple components. Odour threshold is a commonly used term. It is the minimum concentration detectable or…

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Federal Clean Air Act (FCAA)

A federal law passed in 1970 and amended in 1974, 1977 and 1990 which forms the basis for the national air pollution control effort. Basic elements of the act include…

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Hazardous Air Pollutants (HAPs)

Pollutants released into the atmosphere as particles and volatile organic compounds (VOCs) — including the known carcinogens of benzene and toluene — from a variety of sources such as vehicle…

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New Source Review (NSR)

A Clean Air Act requirement that State Implementation Plans must include a permit review,  which applies to the construction and operation of new and modified stationary sources in Non-attainment areas, to…

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Odour intensity

A measure of how strong an odour may be based on an initial perception.  Odour intensity and odour concentration have a non-linear relationship.  For instance, if two distinct odours are…

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Particulate Matter (PM)

Tiny solid or liquid particles that are suspended in air. Particulate matter is produced from a wide variety of sources like natural and human-caused, large and small. They are comprised…

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