For us to sense an odor, odorous molecules must become volatile, that is become a vapor or gas, to circulate in the air and reach our noses and eventually our olfactory lobe. Odor molecules are small to mid-sized molecules. Exactly how these molecules trigger the sensation of smell is not completely understood. One popular theory can be illustrated by a lock and key. Receptors (the locks) at the ends of our olfactory nerves are specially shaped. Only the right shaped molecule (the key) will fit into the receptor activating the sensation of odor.
These nerve endings are truly where our brain meets the outside world. There is a strong connection between odor and memory. Odors can trigger memories. The reverse is also true – when recalling a memory it may include a strong sensation of odor. As with other aspects of odor, women are more sensitive. Seeing a stain where we previously smelled an odor may spark a recall of that odor. The power of suggestion can also create a sensation of odor. This psychological odor is not a real odor but your brain can’t tell the difference.
The real odor is the pure sensation of smell transmitted to the olfactory lobe by the olfactory nerve. These are the odors that are actually in the air and are perceived by our nose and brain. These are the easiest to remove! Real odors must evaporate (be volatile) so they can reach our noses. They must also be water-soluble because the molecules must pass through the mucous that coats the inside of the nasal cavity.
Psychological odors. These types of odors are the hardest to deal with because they are odors that people think they smell based on experience, suggestions, and past impressions. For example: A customer is awakened in the middle of the night to smoke and fire. They escape, but much of their house has been damaged. You (the contractor) clean, replace and deodorize the entire structure and its contents. You don’t smell any smoke. The insurance adjuster doesn’t smell smoke. However, the customer swears they still smell it. The traumatic event has “locked” that odor in their brain. Many times, another odor treatment “show” must take place with the customer present in order to “replace” the “bad” odor with the new “good” odor.
Nature uses heat, light, air movement, decay of organic materials, and ozone to deodorize. Given time, nature would deodorize all odors. The most often overlooked form of deodorizing is air movement. Exhaust fans may be used to remove or dilute malodors or toxic gases by bringing in the fresh air. The problem lies in the amount of time it takes. Therefore, we are called in as professionals are to speed up nature. The tools of the professional include cleaning, chemical, and/or mechanical processes.