08/03/2023   |  

Previously, flowmeters or calibrators used by industrial hygienists were classified as "primary standards" or "secondary standards”. These were definitions derived from metrology and were not a good fit for the instruments you use every day to measure volumetric accuracy of industrial hygiene air sampling pumps. 

ASTM recently released ASTM D5337-23 Standard Practice for Setting and Verifying the Flow Rate of Personal Sampling Pumps. This new standard practice indicates that "primary standard" and "secondary standard" have different definitions in metrology and should NOT be applied to flow calibrators used to calibrate air sampling pumps. The term “working standards with or without traceability" has been introduced to better classify industrial hygiene calibrators such as the SKC chek-mate and other competing models. This Technical Note is a good source of information on the new standard practice. 

It comes down to this…You need your exposure sampling data to be highly accurate. That starts with the accuracy of your air sampling pump’s airflows and ultimately its sample volumes. Verifying air sampling pump airflows with an intrinsically accurate working standard flowmeter with traceability, such as the SKC chek-mate, provides assurance of accuracy, peace of mind, and defensible data.  

Learn more about chek-mate!