Respirator fit testing is recommended for use of all facepieces. As per the AS/NZS 1715 Standard an individual shall be fit tested prior to initial use, whenever there is a change in your facial characteristics or other features which may affect the facial seal of the respirator and should be repeated annually thereafter. Individuals issued powered air purifying respirators and supplied air respirators with loose-fitting facepieces, hoods or helmets are not subject to respirator fit testing.