
Taken from the Enforceable Planning Conditions course
The geographical extent over which the odour can be detected.
The number of households affected (compared to the character of the area i.e. dense or sparsely populated).
The extent or distance over which the complainants claim they can detect odours & that which officers can also detect odours.
The distinct characteristics of the odours and comparison of recognition with detection.
The characteristics of the odour and its acceptability.
The atmospheric conditions which result in odour detection, including wind direction, temperature, wind strength, type of day affected and times of the day.
The atmospheric conditions which reduce or enhance odour detection and correlation with complaints.
The duration of odour impact, the times / periods of respite and whether transient or prolonged - whether absorbed on materials and re-emitted.
The use or activity affected by odour, i.e. daytime, sleep, use of garden etc.
The activity identified by the odour and its social importance or necessity, including historical significance i.e. muck spreading is an established farming activity.
The background olfactory environment, i.e. that which exists in the absence of the source. For example, is it a town centre with lots of take-away odours in the area or is the type of odour wholly unexpected?
Are there any instrumental odour analysis methods available that can be used comparatively.
Can the odorous chemical compounds be identified.
Complainants subjective rating of unpleasantness and comparison with odour known odours. Eg.
EXTREME CARE IS NEEDED IN USE OF THIS APPROACH. IT CAN BE USEFUL TO GAUGE THE REASONABLENESS OF COMPLAINTS AND SEE IF A COMMON VIEW EXISTS
Is odour source totally enclosed, partially enclosed or wholly in the open air?
What are the points of odour emission (one or multiple) i.e. transport, storage, waste, processing.
Are there other impacts on use and amenity from activities at site such as dust, noise or smoke? Does the combined effect result in nuisance?
Dislike of bad smells = Deeply ingrained within human defence mechanism
DETECTION AT VERY LOW CONCENTRATIONS
ODOURS ARE NOT GENERALLY TOXIC BUT AVERSION REACTIONS = NAUSEA & CHANGES TO PULSE AND RESPIRATION.
Sniffing can increase sensitivity some four fold.
10-30 million Nasal receptor cells in the nose of a human.
Peak ability to smell from teens to mid 40's - slow loss follows.
Psuedo - hallucinations of smell can occur due to physical brain damage, infections, drugs or psychological disorders.
Human perception varies. Just perceptible for one person may = strong to another.
Pervasiveness & persistence may relate to odour absorption and subsequent release from materials.
RULE OF THUMB - for compound odours - Nuisance occurs where dilution to detection is approximately 5 (i.e. one fifth of concentration).
NB: BEWARE THIS CAN VARY DRAMATICALLY
ODOUR NUISANCE depends on quality of odour, social and regional factors plus air temperature and humidity.
We offer training for anyone who deals with nuisance issues. We have a range of successful courses for Noise Professionals and Environmental Health Officers. Details of all the courses can be found in Training.
Mike Stigwood MIOA, FRSH.
& Terri Stigwood MRIPH.
A: 14 South Road,
Impington,
Cambridge,
CB24 9PB
T: 01223 441671 or 510430
M: 07867 977222