In order to achieve the highest level of fit testing, it is important to know the various parts of a respirator and how to prepare that mask for testing. Every mask regardless of type will have some form of valve which re-directs the user's breath during the EXHALLATION phase. This is particularly obvious in APR-type respirators where the INHALLATION valves are located inside the filter mount on each side of the mask and are usually in the form of a small, round flap of latex or plastic which covers the hole from the inside. It is imperative that, when utilizing Controlled Negative Pressure testing with the Quantifit or the older FitTester 3000, that these valves be either removed or propped open. If this is not done the valve will close during testing and the test will most likely Fail or Abort. The classic symptom to look for will be a graph line that looks like an earthquake on a Richter scale or the jagged edge of a saw blade. There is nothing else that can produce this unique signature. If you observe this then you have a valve that is closing during the exercise.
Propping open the valve could be as simple as sticking a paper clip in the opening or using one of our Valve prop clips which we have just recently acquired. Call me for details on that part which we sell in batches of ten. 205-980-0180.
-Barry
Propping open the valve could be as simple as sticking a paper clip in the opening or using one of our Valve prop clips which we have just recently acquired. Call me for details on that part which we sell in batches of ten. 205-980-0180.
-Barry
