an assessment of the evidence - Council of Canadian Academies

Influenza Transmission and the Role of PPRE: An Assessment of the Evidence 35Personal Protective EquipmentPersonal protective equipment (PPE) is considered the “last line of defense” againstexposure. In general, the engineering and administrative controls are considered tobe more important in preventing occupational exposures. However, these controlmeasures may not be in place in all situations, or may not be 100 per cent effective.Therefore, PPE supplements engineering and administrative controls.Personal protective equipment is traditionally defined as specialized clothing orequipment personally worn by an individual to protect against a hazard. It includessuch things as goggles, gloves, gowns, surgical masks and respirators.Personal protective equipment is not a substitute for good engineering, work practice,and administrative controls, but should be used in conjunction with these controls toprovide for a safe and healthy workplace. CDC, 2007.The effectiveness of PPE will depend on the safety culture, supervision, and on anindividual’s willingness to properly wear the clothing or equipment as needed.These factors can be addressed through an effective health and safety programinvolving education and training. More than either of the other two measureswithin the hierarchy or control, PPE requires focused attention by the wearer on aday-to-day basis.Personal Protective Respiratory EquipmentPersonal protective respiratory equipment (PPRE) is a sub-category of PPEdesigned to block inhalation of hazardous airborne contaminants. Respiratoryprotection must be capable of preventing the inhalation of influenza viruses viathe mouth or the nose. Many factors contribute to the effectiveness of PPRE inreducing influenza transmission and these must be assessed within the overallcontext of the hierarchy of control.RESPIRATORSRespirators protect the wearer by removing harmful contaminants from the air thatmight be inhaled or by providing a clean, independent source of air to the wearer.There are two types of filtering respirators: (i) for particulate matter, including liquidsand solids; and (ii) for vapors and gases. Particulate respirators can be filtering facepiecerespirators or elastomeric facepiece respirators with attached particulate filters.Examples of these are given in Table 2. The entire surface of a filtering facepiecerespirator serves as the filter. The charge to the panel specifically referenced “N95respirators,” a commonly used term in Canada that refers to NIOSH-certified,disposable, particulate filtering, half-facepiece respirators. In order to remain withinthe charge, only this type of respirator will be discussed.