the scops and application of odor measurement and control are sometimes confused by various uses of the word odor. In the past, odor has been used to mean either(1) the perception of smell, referring to the sensation, or (2) that which is smelled, referring to the stimulus. to eliminate confusion, odor is best used only for the former meaning, and odorant should be defined as any odorous substance. odor intensity, then, is the magnitude of the olfactory sensation produced on exposure to an odorant. odor control is a term that can be used to describe any process that makes olfactory experiences more acceptable to people. the perceptual route to this objective, but not always,the reduction of odor intensity. an alternative route is the change of odor quality in some way that is considered to be an improvement