an assessment of the evidence - Council of Canadian Academies

Influenza Transmission and the Role of PPRE: An Assessment of the Evidence 53elastomeric facepiece: A reusable respirator where the facepiece is cleaned and reused but thefilter cartridges are discarded and replaced when they become unsuitable for further use.engineering controls: Physical controls put in place in an overall exposure plan; these includesuch things as ventilation requirements, ultraviolet lighting, relative humidity and temperaturecontrol and negative pressure rooms.filter efficiency: The ratio of the number of particles trapped by a filter relative to the totalnumber of particles found in the air upstream of the filter.filtering facepiece: A negative pressure particulate respirator with a filter as an integral partof the facepiece or with the entire facepiece composed of the filtering medium.fomite: Any inanimate object or substance capable of carrying infectious organisms (such asgerms or parasites) and hence transferring them from one individual to another.haemagglutinin: A protein found on the surface of the influenza viruses.hierarchy of control: A range of hazard control methods arranged in order of implementationeffectiveness.HVAC: Heating, ventilation and airconditioning.inhalation transmission: A mechanism of transmission of infectious particles via inhalation.This includes particles ranging in size from 0.1 to 100 µm and therefore would encompassthe classical airborne AND droplet modes of transmission.long-range transmission: Inhalation transmission of the virus at distances greater thanapproximately two metres.micrometre (µm): 10 -6 metresmode of transmission: The method by which influenza is spread to other persons.most penetrating particle size (MMPS): The size of the particles that achieve maximumpenetration of the filter medium. Particles that are smaller or larger than the most penetratingsize exhibit a lower rate of penetration.nasopharyngeal-sized particles: Particles having diametres in the range of greater than20 to 100 µm which are usually deposited in the upper respiratory tract above the larynxincluding the inner nasal passages (“nasopharyngeal region”).particle: A generic term for a small mass of either liquid or solid.personal protective equipment (PPE): Clothing and other work accessories designed to createa barrier against workplace hazards. Examples include safety goggles, gloves and face shields.personal protective respiratory equipment (PPRE): A sub-category of PPE designed to blockinhalation of hazardous airborne contaminants.