Doing your own Fit Check (aka seal test)
Please ensure the respirator user performs a fit check before using these in a potentially hazardous setting. We recommend the published CDC NIOSH positive and negative seal check procedure before using the respirator to make sure that it is of proper size and to ensure there weren't any faults during manufacturing/assembling. Do this without filter cartridges installed, ports should be easily blocked with the palms of your hands. How to do a positive pressure user seal check
Once the particulate respirator is properly donned, place your hands over the facepiece, covering as much surface area as possible. Exhale gently into the facepiece. The face fit is considered satisfactory if a slight positive pressure is being built up inside the facepiece without any evidence of outward leakage of air at the seal. Examples of such evidence would be the feeling of air movement on your face along the seal of the facepiece, fogging of your glasses, or a lack of pressure being built up inside the facepiece. If the particulate respirator has an exhalation valve, then performing a positive pressure check may be impossible. In such cases, a negative pressure check should be performed.
Negative pressure seal checks are typically conducted on particulate respirators that have exhalation valves. To conduct a negative pressure user seal check, cover the filter surface with your hands as much as possible and then inhale. The facepiece should collapse on your face and you should not feel air passing between your face and the facepiece. In the case of either type of seal check, if air leaks around the nose, use both hands to readjust the nosepiece by placing your fingertips at the top of the metal nose clip. Slide your fingertips down both sides of the metal strip to more efficiently mold the nose area to the shape of your nose. Readjust the straps along the sides of your head until a proper seal is achieved.2 If you cannot achieve a proper seal due to air leakage, you may need to be fit tested for a different respirator model or size.”
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