odour

Active sources

Have a defined gas flow emitted from source.  Example includes a biofilter or aerated pond.  According to VDI3880, an active source is defined by an average flow velocity of 30m/h…

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Anosmia

Anosmia is the temporary or permanent complete loss of ability to perceive odour. Temporary anosmia can be caused by infection or nasal blockage. Permanent anosmia may be due to damage…

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ASTM E679-04

ASTM E679-04 United States ‘Standard Practice for Determination of Odor and Taste Threshold by a Forced-Choice Ascending Concentration Series Method of Limits’ provides guidance on olfactometry and sampling. The ASTM…

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ASTM Standards

There are a number of ASTM standards related to odour assessment and regulation: ASTM E679-04 United States ‘Standard Practice for Determination of Odor and Taste Threshold by a Forced-Choice Ascending…

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Biofilter

A biological process where a microorganisms (bacteria or fungus) is used to remove pollutants and odour from a gaseous waste stream.  The air stream carrying teh pollutants passes through the packing bed…

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CEN Standards

See EN13725 standard Standard on Determination of Odour Concentration by Dynamic Olfactometry  

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Common Air Contaminants (CACs)

Air pollutants commonly found in the atmosphere, namely carbon monoxide (CO), particulate matter (PM), nitrogen oxides (NOx), sulphur oxides (SOx), volatile organic compounds (VOCs) , ammonia (NH3) and Ground-level ozone…

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Delayed Olfactometry

A time-lag between sampling and measuring of odour concentration where the odour sample is preserved in an appropriate container (odour-netutral material). Can also be referred to as static sampling. Delayed…

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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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Diffuse sources

A source having a specified area or volume that does not have a defined air flow.  Examples include waste dumps, compost piles, sedimentation tank.  An example that is not a…

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