Performance of power assisted respirators during simulated asbestos removal.

Protection factors were measured on full face mask power assisted respirators when worn by experienced asbestos removal operatives under simulated asbestos removal work conditions. The sulfur hexafluoride test method as defined in European Standards was employed to determine the leakage into the respirators. Protection factors were measured on a total of 21 test volunteers. The test method allowed protection factors to be related to wearer activities and practices. Poor fitting techniques and simulated reduction in the respirator's performance resulted in a reduction in the protection factor. Visual inspection of the RPE usually worn by the volunteers identified inadequate maintenance. This study re-emphasises that careful selection, facepiece fit testing and correct use and maintenance of RPE are essential to ensure optimum protection to the wearer.