Laboratory measurements of oil mist concentrations using filters and an electrostatic precipitator.
Leith-D; Leith-FA; Boundy-MG
Am Ind Hyg Assoc J 1996 Dec; 57(12):1137-1141
A study of the potential for samples to evaporate during sampling from filters and substrates used to collect mineral-oil (8012951) mists for personal exposure assessments was conducted. An electrostatic precipitator (ESP) designed for personal sampling at 2 liters per minute (l/min) and preweighed polyvinyl-chloride (PVC) or mixed cellulose ester (MCE) placed in an experimental chamber were exposed to test oil mist aerosols at concentrations of 1, 2.5, or 8mg/m3 for 25 or 60min. The test aerosols were generated from a commercial mineral-oil composed primarily of straight chain aliphatic hydrocarbons containing 14 to 20 carbon atoms. The chamber was then opened and the filters and ESP substrate were reweighed. The filters and substrate were then returned to the chamber and clean laboratory air was passed through each at 2.0l/min for 4 hours (hr). The filters and substrate were then removed from the chamber and weighed once again. Significant losses of collected oil mist, as measured by decreases in the amounts of oil retained on the materials after clean air was passed through them for 4hr, were detected on the PVC and MCE filters and ESP substrate. Across all experiments, the greatest loss occurred on the PVC filters, followed by the MCE filters and the ESP substrate. The difference in loss between the materials was particularly pronounced for the low loading condition, that is, exposure to the 1.0mg/m3 aerosol. At that loading, the ESP substrate retained 3.3 and 5.0 times as much oil as the MCE and PVC filters, respectively. The authors conclude that sample evaporation can occur, particularly when samples of mineral-oil are collected on PVC and MCE filters. This suggests that the type of sampling method used can be very important, especially when mineral-oil concentrations around 1mg/m3 or less are used. Sample evaporation can be minimized by collecting samples with an ESP.
NIOSH-Publication; NIOSH-Grant; Grants-other; Mineral-oils; Oil-mists; Industrial-hygiene; Cutting-oils; Air-sampling-equipment; Laboratory-testing
Aerosol Associates 120 Muir Lane Chapel Hill, NC 27514
Other Occupational Concerns; Grants-other
American Industrial Hygiene Association Journal
Aerosol Associates, Chapel Hill, North Carolina