Additionally, this research identified the possible factors which could contribute to breathing zone concentration variations. This research revealed that the chest sampler provides a consistent relationship to the concentrations measured at the nose for a given job category. Styrene air concentrations detected at the nose were significantly different than those concentrations detected at the other three locations and represented 90 percent, 84 percent, and 76 percent of the left lapel, right lapel, and chest samplers, respectively. Two job classes were studied: the spray gun operators and the rolling and tucking operators. An extensive field investigation in a boat manufacturing plant was conducted where styrene air concentrations were measured by mounting four 3M one-stage diffusion samplers around the worker's breathing zone. It has been generally assumed that vapor is uniformly mixed in the breathing zone therefore, samplers are placed on either lapel or on the chest of the worker. One major limitation with personal samplers is their relatively low flow rate, which can be as low as 2 L/min. A suggested minimum air volume when sampling to determine TWA compliance is 25 L. This zone is considered to have an airborne chemical concentration equivalent to the concentration breathed by the worker. held open side down in the employees breathing zone during sampling. This zone is considered to have an airborne chemical concentration equivalent to the concentration breathed by the worker. Vacuum required for function of flow-limiting orifices.Breathing zone samples are used to estimate worker exposure to airborne contaminants by collecting air from a vaguely defined zone surrounding the head. Breathing zone samples are used to estimate worker exposure to airborne contaminants by collecting air from a vaguely defined zone surrounding the head. Two types of instruments are commonly used to do personal breathing zone sampling: passive monitors and personal. Breathing zone samples provide the best indication of the concentration of contaminants in the air the employee is breathing. Alternatively, the sampling times can be short, sometimes only a few minutes, to deliberately measure how high the exposure is during specific dust-generating operations.xx The breathing zone can be visualized as a hemisphere about 6 to 9 inches around the employee's face. The final result reflects the average level of exposure. breathing zone, within a 0.3 meter radius, such as attached to the shirt. To minimize sample variability, you should sample throughout an entire shift (approximately 8 hours). When placing the sample pump on an individual for personal monitoring or when. Follow the links here to read descriptions of specific procedures for air sampling using MilliporeSigma filters, holders, and cassettes.Īirborne particle contamination can vary significantly depending on the operations being carried out. (Some standards e.g., cotton dust, may necessitate area sampling.) The 'breathing zone' is defined as a sphere approximately 2 feet in diameter surrounding the head. The following section outlines air sampling techniques and includes a general discussion of collecting air samples. For air contaminants having PELs, sampling must be conducted within the breathing zone. General Air Sampling in Work Environments Occupational Safety and Hazard Administration (OSHA) defines the breathing zone as the area within a ten-inch radius of the workers face.
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