Unknown Odor Investigation
On occasion, building occupants have reported odors of unknown cause or origin in both commercial and residential structures. Such odors can be constant or oftentimes, appear intermittently throughout the day with irregular frequency.
Prior to the odor investigation, background information is gathered that can assist HygieneTech in developing an appropriate sampling strategy. Background information can include answers to questions such as: How would you describe the odor?; Have there been any recent renovations, construction activities, and/or new processes in or near the structure?; Does the odor appear to originate from a particular area in the structure?; Is the odor more noticeable at a certain time of day?; Have one or more persons reported the odor?; Are any persons suffering symptoms thought to be related to the odor?; and, Are these symptoms more noticeable when in an area where the odor is detected?
If the odor is constant throughout the day, direct-read and/or grab sampling techniques may be used; if the odor seems to appear only intermittently throughout the day, a longer monitoring period may be necessary to increase the likelihood of detection. Direct-reading air measurements can be performed using a photoionization detector (PID) able to detect gases and vapors at airborne concentrations ranging from 0.1 to 10,000 parts per million (ppm). Direct-reading air measurements can also be collected using a Dräger colorimetric detector tube apparatus equipped with the appropriate detector tube.
Indoor area air samples can also be collected using traditional industrial hygiene air sampling pumps equipped with the appropriate media and/or through use of a MiniCan air sampling canister. These sample collection methods are flexible in that air samples can be collected over short or long-term durations, whereas the PID and Dräger tubes are typically used for screening purposes. Sampling pumps are generally used when particular contaminants are expected or thought to be present. The MiniCan air sampling canister offers the unique aspect of being able to identify whether or not a wide range of volatile organic compounds (VOCs) are present in the collected air sample, which is often useful when the background information fails to identify a possible source of the unknown odor.
