Understanding Odours. What causes them. What they are made up of.
Welcome to our Understanding Odours Page.
1. Odour Control.
Bad odours exist not only in the home but everywhere else such as in commercial buildings, shops, outdoors or what about animal rendering plants, chicken factories, landfill sites, or effluent plants!!
By understanding odours and the problem associated with them, you can start to identify what do-it-yourself odour control techniques to use and even which odour control products to purchase.
2. The make up of Odours.
For understanding odours and odour control you first need to understand the make-up of odours.
There are basically three elements that cause most foul odours. These are Nitrogen, Oxygen and Sulphur. They can all be found everywhere. Fortunately not all odours are bad. Those containing oxygen are usually sweet whilst those with nitrogen and sulphur are usually foul.
The parent compound of the Nitrogen is normally ammonia, found in lots of household and industrial compounds such as glass cleaners and smelling salts. Whilst pungent, ammonia is not normally considered foul unlike organic derivatives of ammonia.
Amines such as dimethylamine and trimethylamine give rise to fishy odours, and higher amines such as tetra and penta-methylenes arise from the putrifaction of flesh.
Ammonia derivatives are also associated with pet urine.
Sulphurous odours are normally associated with rotten eggs and organic derivatives such as butyl mercaptan with animals such as the skunk.
3. Detecting odours.
In order to detect odours the responsible compound needs to be volatile and therefore be dispersed in the air we breathe. Once airborne the compound can stimulate the olfactory glands in the nose and cause a number of complex reactions resulting in what we know as smell.
With some compounds only a few molecules may be needed to cause this reaction, whilst others are capable of blocking odours when in high concentrations and become no longer detectable above certain levels. This in fact is very dangerous as it may be a lethal compound such as Hydrogen Sulphide.
Many foul smells are formed by dead and decaying matter and during the process of decay the organic material breaks down into other, volatile, compounds giving rise to the smell.
4. Chemical Masking and Neutralising Products.
Odour control can be achieved in two different ways. Masking and neutralising.
Masking is the concept behind air fresheners in that a pleasant smell is introduced in high enough concentrations to mask the unpleasant smell. The nose then only detects the pleasant smell that gives rise to a fresh smell.
The only downside to this approach is that the bad smell is not removed but stays in the background and any masking may need to be continually repeated to hide the smell.
Neutralisation is the process that nullifies the odour-producing chemical, including those persistently produced. During this process the specially formulated agent is atomised and absorbs the odour-producing compound, neutralising the compound.
The result is not just the elimination of the unpleasant smell but a light and fresh aroma to the location.