Occupational hygiene survey Essay Example | Topics and Well Written Essays - 1500 words

Occupational hygiene survey - Essay Example The weight of dust sample was used to determine the exposure level of dust. Besides, the samples were chemically analyzed to determine the level of resin acids. In addition to that the details of the subject, environmental factor like temperature and relative humidity was recorded Air samples were collected too for analysis of microbiological content. Sampling was done several areas. Samples were collected simultaneously for a sampling period of 5 minutes. A sample was collected outside the gate of the factory to be a representative of ambient condition. Samples were then sent back to the laboratory for analysis. A seven-hole inhalable dust sampler (JS holdings, UK) was used to collect dust sample. The sampler was with 0.45m pore sizes, 25mm diameter Teflon Filters (Costar). This device was used to collect sample inhalable, as if inhalation through one's nose. The resemblance of the mechanism allowed study on health hazards by the dust inhaled. Teflon filter were used in order to collect particles for resin acids analysis. In the study, air was drawn through the sampler at the speed of 2 litre/minute. Four samples were taken for each location respectively. The weight of dust was determined by subtracting the pre-weight of the filter from the post-weight. All the weight measurement was conducted on the micto-balance (0.001mg sensitivity). Samples were equilibrated to the same temperature and relative humidity. All readings were taken at temperature 20+0.5 C and 50% relative humidity. Resin Acid Analysis There are two categories of resin acids: abietic and pimaric acid. The amount of acids exist in the dust depends on the species, maturity and storage condition. Method used to analyze resin acid was developed by Victor Leong and Mary Ellen Cassinelli (Pengelly, 1994). The quantity of abietic and pimaric acid was determine by a gas chromatography methodology. From the previous analysis, the Teflon filters were shifted into 100mm glass tubes with phenolic caps. 3ml of dichloromethane was used to extract the filters under ultrasonic bath for 30minutes. The extract was filtered with 24mm diameter 0.45 m pore nylon syringe filters. It was then washed with 0.5 ml of dichlorometh