Odour characteristics and detection threshold
This is a qualitative attribute which is expressed in terms of
“descriptors”, e.g. “fruity”, “almond”, “fishy”. This can be of use when
establishing an odour source from complainants’ descriptions. Alternatively, it
may be possible to identify key chemical components by a description of their
The “amount” of odour present in a sample of air.
It can be expressed in terms of ppm, ppb or in mg/m3 of
air for a single odorous compound. More usually a mixture of compounds are
present and the concentration of the mixture can be expressed in odour units
per cubic metre (ouE).