Any part of an exposure assessment that uses air samplers as a primary means of collecting gaseous vapors or particulates, must check the flow rate of the air sampler. This is done to calculate the volume of air for the vapor or dust taken in and to determine the airborne exposure concentration. Your portable airflow calibrator is one of the many components used in a chain that will determine the ultimate results for comparison to an exposure standard. You must minimize error to the maximum extent.
MINIMIZING SAMPLER FLOW RATE ERROR
According to OSHA and NIOSH sampling and analytical guides, establishing the correct volume of air through a filter or sorbent media is essential for a more accurate calculation of concentration. The flow rate of an air sampler is calibrated with the sampling media in line using a field flow calibrator. Some air samplers have a built in calibrator or the use of dry piston prover field calibrator. The flow should be checked before and after each sample. IF the volumetric flow uncertainty is known, concentrations can be ultimately presented as data in lower and upper confidence limits. This will provide better data for OSHA compliance and engineering controls. Many of the calibrators come in reading modes of single, continuous, and burst.
FLOW CALIBRATOR CALIBRATION AT CIH EQUIPMENT COMPANY
CIH uses the MESA Laboratories ML800 primary piston prover for unmatched accuracy. The ML-800 is a positive displacement primary piston prover for gas flow measurements in either pressure or vacuum applications. Using Proven DryCal Technology, it combines the accuracy of a primary standard with unequaled speed and convenience. Volumetric or standardized flow readings are obtained with the push of a button. The ML-800 can be set to take flow readings manually, (one reading at a time), or automatically in the continuous auto-read mode. The ML-800 can be programmed for up to 100 readings in an averaging sequence.
Why calibrate your field flow calibrator?
- A calibrated field flow calibrator coupled with a calibrated air sampler provides the most accurate measure of volume
- CIH Equipment Company uses the Mesa Laboratories ML800 primary standard, has a very low uncertainty, and is considered the best in the business.
- Field flow calibrators may be reading poorly due to piston stickiness, temperature, atmospheric pressure, age, and shock.
- Flow calibration is in our A2LA scope of accreditation and error is minimized with our low uncertainties.