Why Tapelift Samples
Air Quality and Surface Sampling using Tape
Our concern is about human health and the sense of well being. We have assumed that testing the air is the best way to assess exposure. That is the same assumption that was made in London during the great Cholera outbreak in the mid-1800’s. A fellow by the name of Steven Johnson has written a book about that called THE GHOST MAP. It is an interesting study of the persistence of the official requirement for taking air samples and the actual cause of Cholera (the water) that was demonstrated by John Snow. Thousands of lives could have been saved had it not been for the insistence on air samples to monitor exposures. It was noticed that the source of water seemed to be related to the outbreaks of cholera years earlier but in the opinion of William Farr, the “official” statistician for London, it had to be an airborne disease. Today John Snow’s work is a classic that all industrial hygienists study as part of their training. Just as back then, the official approach is air sampling. There is a disregard for the human being as an environmental sampling device. We are not static air pumps. Not even a simple examination of the physics of airflow over the body would allow such a flawed model. That is acknowledged but we take air samples anyway.
Everyone agrees that in order to sample the air quality in an environment it is necessary to take samples over a long time or repeated short-term samples over a substantial period of time. The time interval should include all cyclic events in the workspace and, ideally, have a temporal resolution sufficient to identify events that may result in discomfort. That can be done for gases (including water vapor as RH) and temperature. It is much more difficult for particles. It is assumed that small particles are the only ones that are collected by the respiratory system so we can sample particles that behave almost like gases. That assumption is wrong but it is “almost right”. Can clients afford the proper air sampling protocol? No!! So what do we do? We take one air sample, or maybe 20 while we are there. Each one represents a brief interval of time that may have nothing to do with the exposure that caused the problem. If there is not a CO2, O3, RH, or temperature problem we assume things must be OK. VOC, formaldehyde, or mold spores may be a problem. Particles other than mold are not considered because the standard air sampling devices do not efficiently collect particles that are known to cause problems. As a result, the main cause of the “sick building syndrome” (SBS) or “Building Related Illness” (BRI) has gone unidentified “Officially”, just like the cause of Cholera in London. The fact that the symptoms of SBS or BRI coincide with the symptoms caused by glass fiber is not a mistake. The presence of glass fiber on surfaces correlates well with the occurrence of these complaints, as documented in numerous studies here and in Europe.
The larger question still remains. Do you want to test the air quality or do you want to determine if the environment will have a detrimental effect on individuals exposed to it? The air needs to be tested and needs to be within certain tolerances for optimal performance of the workers in that environment. If there are still health complaints it is probably not the air that is the problem. Surfaces must be tested.
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