Aerosols Handbook: Measurement, Dosimetry, and Health Effects. N. H. Harley and L. S. Ruzer, eds., Boca Ratan, FL: CRC Press, 2004 Jul; :225-264
The observation of occupational exposure to aerosols has a long history, but great progress has been made in the past several decades in providing a range of measurement instruments and techniques. While dose/response relationships have been established for a wide range of workplace contaminants, there are still uncertainties as to which metric is the most appropriate to measure for specific contaminants. Current research emphasis on the ultra fine aerosol particle range may result in surface area being considered as an important exposure metric. When attacking the problem of what instruments or approaches are to be used in making workplace measurements, a number of factors have to be considered. The size range of interest, the aerosol metric (size, mass, number surface area, radiological, chemical, Or biological activity concentration), and purpose of measurement (compliance with standards, evaluation for source control, personal vs. environmental exposure) all have an impact on the selection of the most appropriate type of measurement technique or instrument. Because aerosol particles have a whole range of properties that can affect their measurability, one needs to have an adequate understanding of the aerosol to be measured and how its properties may affect the selected measurement technique. The development of readily available, accurate direct-reading measurement tools (e.g., the SMPS and the APS) has spawned a range of classifiers and other aerosol measurement techniques. Many of these are innovative and have definite advantages over the traditional approaches to sampling and measurement. However, one has to be cautious in ensuring that adequate testing of these devices has been performed and that one understands the advantages and drawbacks of any instrument selected. The literature is replete with discoveries of subtle biases introduced by new devices that initially appeared to have clear advantages over traditional approaches. On the other hand, some traditional approaches were not carefully tested when they were originally selected and also have significant drawbacks. Hopefully, with the development of new instrumentation and appropriate testing, clearer choices and better characterized measurement tools will be available in the future.