What is the flow rate range specified by NIOSH 7400?

The flow rate range specified by NIOSH 7400 is important because it establishes the recommended parameters for sampling airborne concentrations of asbestos fibers. A flow rate in the range of 0.5 to 16 liters per minute is considered effective for ensuring accurate and representative sampling. This range ensures that an adequate volume of air is drawn through the sampling medium while minimizing the risk of filter overload and maximizing detection sensitivity.

Maintaining flow rates within this range is crucial for achieving reliable results, as it impacts the collection efficiencies of asbestos fibers. If the flow rate is too low, not enough air is sampled to obtain a representative measurement, while if it’s too high, it could lead to the loss of small or light fibers, thus compromising the integrity of the sample.

This range reflects the practical considerations required during air monitoring for asbestos, aligning with industry standards to ensure consistency and reliability in occupational health assessments. The other options do not conform to the accepted flow rates outlined in NIOSH 7400, which is essential for effective asbestos sampling in the workplace.