NIOSH Creates “PAPR100” Class of Respirator
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An interim final rule published by NIOSH in the Federal Register April 14 creates a new class of powered air-purifying respirator (PAPR) that may be better suited to the needs of workers in the healthcare and public safety industries who require protection from COVID-19, according to an agency press release. Because they are designed to filter chemicals, bloodborne pathogens, and aerosol-transmissible diseases, PAPRs with high-efficiency filters, which NIOSH designates as PAPR class HE, are often used in high-hazard procedures in healthcare settings. According to NIOSH, PAPRs played a key role in respiratory protection programs during emergencies related to the outbreaks of Severe Acute Respiratory Syndrome (SARS) in 2002, H1N1 influenza in 2009, and Ebola virus in 2014. However, the size and weight of current PAPR HE devices is considered to be an impediment to their wider adoption in healthcare. Both healthcare workers and first responders would benefit from additional PAPRs during the COVID-19 pandemic, the agency stated. To achieve NIOSH approval for PAPR class HE, a device must pass a silica dust loading test. This requirement, established in 1972, was intended to ensure the device could meet the needs of workers in industrial environments such as mining and milling operations. To provide enough airflow to pass the silica dust test, PAPRs need batteries and fans, which increases their size and weight. The new “PAPR100” class of respirator created by the NIOSH rule replaces the silica dust test with aerosol tests, which allow for smaller, lighter designs. A sodium chloride aerosol will be used to test filters for the N-series PAPR100, which are not resistant to oil. For the oil-resistant P-series PAPR100 filters, NIOSH will use a dioctyl phthalate aerosol test.
NIOSH expects the addition of new PAPRs to the marketplace to help alleviate the strain on respirator supplies in healthcare facilities, many of which are running low on N95 particulate filtering facepiece respirators during the COVID-19 pandemic. According to NIOSH, PAPRs have several advantages over N95 FFRs. Unlike N95 FFRs, PAPRs are reusable, and have a higher assigned protection factor as determined by OSHA. Loose-fitting PAPRs do not need to be fit tested and can often be worn with facial hair. The idea for a PAPR100 class originated during a series of public meetings NIOSH held between 2003 and 2008 to investigate a new PAPR concept. Participants at the meetings discussed issues related to PAPR certification requirements, the possible elimination of the silica dust test, and the incorporation of warnings for low airflow, pressure, and battery life. A subsequent Institute of Medicine workshop held in 2014 explored the unsuitability of PAPR requirements for use of the devices in healthcare. Although the NIOSH interim final rule went into effect immediately, the agency is accepting comments through August 12. For information on submitting comments and a full discussion of the interim final rule, see the notice in the Federal Register. Descriptions of the standard testing procedures for classes HE and PAPR100 are collected on the NIOSH website.
NIOSH expects the addition of new PAPRs to the marketplace to help alleviate the strain on respirator supplies in healthcare facilities.