Background: Acute and chronic exposure to xylene can result in a range of negative health effects.
However, xylene is widely used and emitted in the air of workplaces.
Objectives: To evaluate xylene vapor concentrations to guide the design and evaluation of a local exhaust
ventilation (LEV) system to reduce exposure in a pesticide production factory.
Method: A real time volatile organic compound (VOC) monitor was used to determine the workers’ timeweighted
average (TWA) exposure. A LEV system was designed, and then, workers’ exposure to xylene
vapor was evaluated.
Results: We found that worker’s exposure to xylene (4.7¡5.5 ppm) was lower than the standards
recommended by the American Conference of Governmental Industrial Hygienists (ACGIH) and the
Occupational safety and health administration (OSHA). Despite the low TWA exposures, the short-term
exposures for some workers were higher than STEL levels. Three canopy hoods were designed and
installed with capture velocities of 0.508 m second21 and duct velocity of 10.16 m second21.
Conclusion: We found that an exhaust ventilation system had a significantly reduced occupational
exposure to xylene vapor.