To say that the least understood and most troublesome problem encountered in air pollution work today is malodor falls just shy of understatement. As the technology to deal with this problem is collected and understood, it will become apparent that the conditions described in the foregoing statement are not, as a matter of fact, justified.
It is true that the underlying phenomenon of olfaction, its physics, biophysics, and psychology are not yet well defined. This undoubtedly has many adverse affects in practical odor control work. It does not mean, however, that a practical technology does not exist, for it almost certainly does. The constraints that exist in this troubled area result largely from lack of true knowledge at all levels by those engaged in it. For example, there is a belief virtually universal among pollution authorities and industry that chemical additions, especially if they are perfume materials, to malodorous effluents simply will not work. That all odors are chemical and will respond to chemical alteration goes unnoticed in this belief.
The result is that all sorts of hardware and equipment are required by authorities and installed by business in an attempt to solve the problem. With very few exceptions, it should be evident that the only time any equipment works at all is when it incorporates chemicals of some form. It should be overwhelmingly clear that chemicals and only chemicals can solve odor problems. That it is not clear is robustly evident in the present confused state of the art.