Coronavirus Illness 2019 (COVID-19)


Who this steering is for: use by federal, state, and native public well being officers, respiratory safety program managers, occupational well being service leaders, an infection prevention and management program leaders, and different leaders in healthcare settings who’re answerable for creating and implementing insurance policies and procedures for stopping pathogen transmission in healthcare settings.

Function: This webpage describes concerns for using powered air-purifying respirators (PAPRs) to offer respiratory safety to healthcare practitioners (HCP) as a element of a formally developed and applied written respiratory safety program. It addresses standard, contingency, and disaster surge PAPR use and upkeep practices.

This interim steering relies on what’s at the moment identified concerning the transmission and severity of coronavirus illness 2019 (COVID-19).

The US Facilities for Illness Management and Prevention (CDC) will replace this steering as wanted and as further info turns into out there. Please examine the CDC COVID-19 web site periodically for up to date interim steering.

Standard capability methods needs to be included into on a regular basis practices.

Contingency capability methods needs to be used when shortages are predicted however provides can be found.

Disaster capability methods needs to be used throughout identified shortages.


NIOSH-approved respirators can be found in many sorts, fashions, and sizes from many producers for all kinds of makes use of in lots of occupational settings. The most typical kinds of respirators in healthcare are N95 filtering facepiece respirators (FFRs), surgical N95 FFRs, and PAPRs.

Of those three choices, many healthcare practitioners are the least aware of PAPRs. A PAPR is an air-purifying respirator that makes use of a blower to power air by filter cartridges or canisters and into the respiration zone of the wearer. This course of creates an air circulate inside both a tight-fitting facepiece or loose-fitting hood or helmet, offering a better assigned safety issue (APF) than the reusable elastomeric non-powered air-purifying half facepiece (half masks) or N95 FFRs. A PAPR can be utilized for cover throughout healthcare procedures through which HCP are uncovered to better dangers of aerosolized pathogens inflicting acute respiratory infections.

A PAPR could have a tight-fitting half or full facepiece or a loose-fitting facepiece, hood, or helmet. It has an OSHA APF of not less than 25 for loose-fitting hoods and helmets, 50 for tight-fitting half masks, and 1,000 for full facepiece varieties and a few loose-fitting hoods and helmets the place the producer’s testing has demonstrated an APF of 1,000.

CDC has revealed suggestions for HCP respiratory safety and of generally used NIOSH-approved, FDA-cleared, single-use filtering facepiece N95 surgical respirators.1 Correctly fitted FFR and half facepiece reusable elastomeric respirators are anticipated to scale back exposures to one-tenth of the focus that’s within the air, primarily based on OSHA’s APF of 10 for these respirator varieties. All PAPR APFs exceed the APF of 10 for N95 FFR or elastomeric half facepiece respirators.2

PAPRs scale back the aerosol focus inhaled by the wearer to not less than 1/twenty fifth of that within the air, in comparison with a 1/tenth discount for FFRs and elastomeric half facepiece air-purifying respirators. OSHA assigns an APF of 1,000 to some PAPRs with hoods or helmets. Nonetheless, employers should have proof offered by the respirator producer that testing of those respirators demonstrates efficiency at a degree of safety of 1,000 to obtain an APF of 1,000. Absent such proof, PAPRs with loose-fitting helmets or hoods have an APF of 25. When used correctly, PAPRs present elevated safety and reduce the probability of an infection transmission to the wearer as in comparison with FFRs and half face reusable elastomeric respirators.

Quite a lot of NIOSH-approved PAPR designs can be found. Examples embrace these with tight-fitting facepieces and loose-fitting hoods or helmets, blower types, battery varieties (e.g., Lithium ion, Nickel-Steel hydride, Nickel Cadmium) or over-the-counter disposable batteries, and excessive effectivity (HE) filters or filter cartridges. HE filters are 99.97% environment friendly towards 0.3 micron particles. A PAPR could have adjustable air circulate charges for added consolation and a spread of cartridge protections a few of that are solely for particulates (HE filters) and others which additionally defend towards chemical gases and vapors that can be utilized to assist defend towards hazards related to the dealing with of sure hazardous medication and cleansing/disinfecting operations. The substantial PAPR product variety supplies flexibility to customise safety wanted in a healthcare setting.

Free-fitting NIOSH-approved PAPRs have a number of benefits over tight-fitting non-powered permitted air-purifying respirators, together with3:

  • A match check will not be required for PAPRs with loose-fitting headgear akin to hoods and helmets.
  • PAPRs with loose-fitting headgear will be worn with a restricted quantity of facial hair.
  • Some fashions supply cartridges for particulate and/or fuel/vapor safety.
  • Hooded PAPRs and PAPRs with helmets could supply restricted to important splash safety for the face and eyes.
  • PAPR techniques have assigned safety elements (APF) of not less than 25 (and as much as 1,000 in some instances, as described above).
  • Some PAPRs have disposable, loose-fitting headgear and sufferers can see the face of the HCP, offering for higher interpersonal communication.
  • Most PAPR elements will be cleaned, disinfected, re-used, and shared.
  • PAPRs use solely HE filters, which have a better filtration effectivity towards the smallest pathogen particles in comparison with N95 FFRs.
  • A PAPR could also be much less taxing from a physiological/respiration resistance perspective than different respirators.

The power ought to assess the restrictions and elements related to utilizing PAPRs when contemplating their use in healthcare settings, together with:

  • A PAPR could intervene with the HCP’s visible subject due to the restricted downward vertical subject of view.
  • The HCP’s capability to listen to could also be lowered due to the blower noise, and noise induced by the motion of a unfastened head protecting.
  • The HCP’s capability to make use of of a stethoscope could also be restricted.
  • PAPR batteries should be recharged or changed.
  • PAPRs require a big quantity of cupboard space in between shifts.
  • The power should prepare HCP’s or different workers to keep up and correctly disinfect and clear the PAPR.

NOTE: PAPR HE filters utilized in business are usually re-used till they’re dirty, broken, or scale back PAPR air circulate under specified ranges. Warning needs to be used when utilizing the filter for a reside virus, and a sensible alternative cycle needs to be applied till extra is thought.

Standard Capability Methods

OSHA-Compliant Respiratory Safety Program Necessities

When respirators, together with PAPRs, are used to scale back inhalation exposures, OSHA requires a written respiratory safety program in compliance with OSHA 29CFR1910.134, and the respirators should be NIOSH-approved.4 To be thought of NIOSH-approved, the PAPR meeting can’t be modified from its permitted configuration, and solely these alternative components specified and offered by the producer should be used. The producer’s PAPR directions are particular to a respirator mannequin’s supplies and specs. Directions are usually supplied with the PAPR facepiece, blower, and battery packaging. All directions should be rigorously adopted.

OSHA additionally permits employers to make use of the cleansing suggestions offered by the producer of the respirator, offered such procedures are as efficient as these listed in Appendix B- 2, which means that the respirator is correctly cleaned and disinfected in a fashion that stops harm to the respirator and doesn’t trigger hurt (e.g., pores and skin irritation) to the person.5

PAPRs could also be utilized in healthcare for a wide range of functions. As a result of they supply greater APFs than N95 FFRs and reusable elastomeric half facepiece respirators, PAPRs are appropriate to be used when aerosol-generating procedures are carried out, by hospital first receivers, or when the respirator person will not be in a position to put on a tight-fitting respirator. For efficient use, PAPR producer directions should be adopted.

The elements of NIOSH-approved PAPRs fluctuate significantly amongst producers, they usually react in another way to cleansing and disinfection options and procedures. Producers’ cleansing and disinfection options and procedures additionally fluctuate. These necessary upkeep actions could cause harm or deteriorate PAPR facepieces, headgear elements (hoods, helmets), respiration tubes (hoses), and batteries. If cleansing and disinfection options and procedures are ineffective, HCP could also be liable to contact transmission. For these causes, producers usually suggest that the filter element be discarded. Some employers could possibly observe manufacturer-specific directions for standard use, however the price of doing so could make PAPRs a much less fascinating resolution to attain the mandatory safety.

Cleansing and Disinfection of PAPR Parts

PAPR use requires a strong upkeep program for repairing or changing elements which have grow to be broken throughout use, or throughout cleansing and disinfection and battery administration procedures.6 Competent, educated workers are required to assist the PAPR upkeep program.

Producers suggest cleansing and disinfection procedures for PAPR elements aside from the HE filter/cartridge, which they often suggest be discarded and changed. Filter cartridges will be reused till they grow to be so clogged that they scale back airflow or grow to be visibly dirty or broken. Clogging will not be anticipated to be a think about non-dusty environments akin to healthcare settings. The skin of the filter cartridge can have floor cleansing and decontamination whereas the remainder of the unit is being serviced. Viruses and micro organism inflicting acute respiratory infections can survive on respirator elements for variable intervals of time, from hours to weeks. Consequently, contaminated respirators should be dealt with, cleaned, and disinfected correctly to scale back the opportunity of the machine serving as a fomite and contributing to illness transmission.7 Based on OSHA, the employer could use different commercially out there cleansers of equal disinfection high quality if their use is beneficial or permitted by the respirator producer.

Standard use requires cleansing and disinfecting utilizing both the procedures in OSHA’s Respiratory Safety Customary or the procedures beneficial by the respirator producer, offered they’re not less than as efficient as OSHA’s.8 If an alternate process is used to wash and disinfect the PAPR and its elements, it should be beneficial or permitted by the producer.

Generally, cleansing and disinfecting consists of dissembling the PAPR, cleansing and disinfecting elements, totally rinsing elements, and reassembling the PAPR when elements are dry. You will need to observe all steps set forth within the producer’s directions. Cleansing is beneficial after every use, however the PAPR should be cleaned as usually as obligatory to forestall them from changing into unsanitary.

As with reusable elastomeric respirators, producers usually suggest PAPR HE filters and filter cartridges are to not be cleaned or disinfected. Not like reusable elastomeric respirators, PAPRs use solely HE filters. These filters can differ of their look and their attachment on, or match into, the blower meeting. Routine upkeep can also be required for battery charging, and/or alternative. The upkeep program for PAPRs requires a provide of alternative elements, together with HE filters/cartridges to assist and preserve PAPR use.

CDC has offered thorough info on disinfecting gear and surfaces probably contaminated by coronaviruses.9 Particular directions for cleansing and disinfecting PAPRs should not addressed.

Some disinfectants are highly effective germicides, and their use requires particular precautions akin to satisfactory air flow, use of unpolluted non-sterile gloves, robes, or face shields. Care should be taken throughout cleansing and disinfection to make sure the cleansing workers doesn’t self-infect or injure themselves performing this work.

Cleansing and disinfection should be performed by competent educated people. Centralizing this exercise can guarantee it’s correctly performed.

Contingency and Disaster Capability Issues for Filter/Cartridge Cleansing and Disinfection

Due to necessity, PAPR elements together with filters could also be handled in another way for his or her cleansing and disinfection. Whereas standard apply is to discard the filters after every use, contingency or disaster practices could necessitate cleansing and disinfecting the filter. The efficiency of some filter media will be degraded by contact with the disinfectant.

  • Throughout surge conditions, when producer directions should not out there or satisfactory, and provide shortages exist, interim alternate procedures cleansing and disinfection procedures could also be obligatory and efficient to reuse scarce or unavailable alternative elements. Nonetheless, interim alternate procedures may improve the chance of contact transmission or harm to the filter media if not performed correctly. Alternate procedures and dangers should be thought of to guard HCP and meet healthcare wants.
  • OSHA and producer directions for cleansing and disinfection lack particular particulars for implementing standardized procedures throughout healthcare use. They depend on the person to enhance their common cleansing and disinfection directions. Subsequently, healthcare amenities want to ascertain procedures that will likely be efficient to render focused pathogens inviable and never harm PAPR elements meant to be re-used.
  • Most PAPR elements will be cleaned, disinfected, and if not broken, reused many instances. PAPRs use solely HE filters or filter cartridges. These will be very completely different in dimension, form, and look.
  • Some filters are contained in a protecting cartridge hooked up onto the blower meeting. These could have openings within the cartridge housing that expose the filter media, or they could be considerably protecting enclosing the filter media that can not be seen externally.
  • Different filters should not contained in a cartridge. These could also be inserted into the blower meeting stopping filter media from outdoors exposures together with cleansing and disinfectant wipes.


  • When eradicating natural and inorganic matter from the PAPR elements, educated personnel ought to put on nitrile gloves to guard their arms and restrict the potential for self-infection. Further protecting gear akin to robes and face shields, in addition to air flow, could also be required throughout cleansing and disinfection procedures. Cleansing resolution contact with the filter media should be prevented.
  • A detergent or cleaning soap and heat water could possibly be used to wash the floor of the outside filter cartridge previous to disinfection. Fastidiously keep away from contact with the filter media. Cleansing will be performed utilizing a clear, delicate material dampened with heat water roughly 49°C (120°F) containing a light pH impartial (pH 6-8) detergent and utilizing a mechanical wiping motion. Any element uncovered to moisture throughout the cleansing course of must be rigorously and totally dried. Different PAPR elements could usually be cleaned utilizing the producer’s beneficial procedures.


The effectiveness of an alternate filter cartridge disinfection resolution and process could also be unsure:

  • All crevices of many filter cartridge housings will not be reached with ample disinfection resolution or be contacted for the time frame required to be efficient.
  • The filter media could also be degraded by contact with the disinfectant.
  • Filters and filter media should be rigorously and totally dried. Any remaining fugitive moisture may promote the expansion or sustainability of sure pathogens.

Some PAPRs have  filter cartridges or blower assemblies that forestall disinfectant contact with the filter media. If out there, these PAPRs needs to be used within the contingency or disaster capability technique approaches. These PAPR designs present added assurance that the filter media won’t be contacted with the cleansing and disinfection options. These filter cartridges, in addition to PAPR blowers could also be wiped down repeatedly.

NOTE: PAPR HE filters utilized in business are usually re-used till they’re dirty, broken, or scale back PAPR air circulate under specified ranges. Warning needs to be used when utilizing the filter for a reside virus, and a sensible alternative cycle needs to be applied till extra is thought.

Practices not permitted by the producer can improve the chance and uncertainty of re-using broken or degraded elements. This should be balanced towards different out there HCP safety choices to maintain efficient HCP safety and affected person care.

Alternate procedures used throughout emergencies needs to be assessed and documented within the written RPP, together with alternate cleansing and disinfection practices.

For disinfection, diluted family bleach options, alcohol options with not less than 70% ethyl alcohol, and EPA-registered family disinfectants to be used towards coronaviruses are efficient.

To be used of diluted family bleach options, observe disinfectant producer’s directions for correct disinfectant utility, PPE, and air flow.

  • Test to make sure the product will not be previous its expiration date.
  • By no means combine family bleach with ammonia or another cleanser. Unexpired family bleach will likely be efficient towards coronaviruses when correctly diluted.
  • Most family bleach options include 5.25% sodium hypochlorite (50,000 ppm out there chlorine) to as much as 12.5% sodium hypochlorite (~125,000 ppm). You will need to examine the product label and observe the disinfection instructions to be used, dilution, and speak to time. Alter the ratio of bleach to water as wanted to attain acceptable focus of sodium hypochlorite.
    • Based mostly on the EPA Record N: Disinfectants for Use In opposition to SARS-CoV-2 merchandise, 2500 ppm (0.25%) for five minutes is efficient. Most available bleach is roughly 6% so 2/3 cup of bleach per gallon of chilly faucet water (1:24 dilution) for five minutes is acceptable.
    • For bleach preparations containing 5.25% sodium hypochlorite, use ¾ cup of bleach per 1 gallon of chilly faucet water for five minutes.
    • If a decrease focus of bleach is desired, the EPA normal disinfection fee for hypochlorite merchandise is 600 ppm for 10 minutes. That’s, use 3 tablespoons of bleach per 1 gallon of chilly faucet water for 10 minutes.
  • Put together a contemporary bleach resolution every day in a well-ventilated space. At all times add bleach to chilly water, not water to bleach.

Merchandise with EPA-approved rising viral pathogens claims exterior iconare anticipated to be efficient towards SARS-CoV-2. Comply with the producer’s directions for all cleansing and disinfection merchandise (e.g., focus, utility technique and speak to time, and so forth.).

Disinfectants listed on the EPA’s Registered Antimicrobial Merchandise for Use In opposition to Novel Coronavirus SARS-CoV-2, the virus that causes COVID-19, could possibly be used to inactivate the virus.10 These meant to be used with delicate surfaces could also be most popular.

CAUTION: The next could degrade or harm the respirator elements.

  • Robust options akin to hypochlorite, iodine and excessive concentrations of alcohol could degrade, deteriorate or extract chemical components from sure PAPR supplies.
  • Healthcare sterilization processes together with ethylene oxide shouldn’t be used until approved by the respirator producer as they could degrade and alter the form of the facepiece.
  • Steam sterilization gear shouldn’t be used until indicated as protected for the use by the particular respirator producer.
  • Some EPA-approved disinfectants are additionally out there as prepared to make use of at 2700 ppm for 1 minute; nonetheless, these sturdy options may impression the integrity of the respirator elements.

Steps for cleansing and disinfecting PAPR elements

The next is a common step-by-step course of for cleansing and disinfecting PAPR elements. PAPR producers could not authorize these steps; nonetheless, throughout disaster operations when standard procedures should not possible, these steps may prolong the provision of PAPR elements.

If alternate cleansing or disinfection directions are approved, it is very important observe the ability’s established an infection management practices for cleansing natural and inorganic supplies and infectious organisms together with the virus that causes coronavirus illness 2019.

Healthcare practitioners ought to all the time put on the required correct private protecting gear (PPE) throughout cleansing and disinfecting respirator elements. These employees ought to all the time observe the disinfecting agent producer’s person directions concerning usability, utility, dilution ratio and speak to time, and guarantee all elements are totally rinsed with clear, heat water and totally dried earlier than use or storage. As well as, PAPR facepieces or headgear worn by a couple of person should be cleaned and disinfected earlier than being worn by a unique person in shared conditions.

There are a number of fundamental steps to wash and disinfect PAPR elements – dissemble, clear, disinfect, rinse and dry, examine, restore or exchange, and retailer. The order and particulars of every step are necessary. PAPR elements will be saved and reassembled, or reassembly will be performed earlier than use.

    1. Detach the battery pack, respiration tube, waist belt, facepiece/headgear, and filter/cartridge from the motor/blower meeting. If a respiration tube disposable cowl was used, discard it correctly.
    2. First clear the floor of every PAPR element aside from the filter media after every use. Eradicating natural and inorganic supplies from the element surfaces will assist obtain maximally efficient disinfection.11
    3. Utilizing a mechanical course of, clear all elements (besides filter/cartridge and respiration tube disposable cowl) of the PAPR meeting with a clear, delicate material dampened with heat water that’s roughly 43°C (120°F), containing a light pH impartial (pH 6-8) detergent.
      Warning: Don’t soak, dip or immerse PAPR elements within the cleansing or disinfection options until particularly beneficial by the producer.
      • Don’t permit liquid to enter the air outlet or inlet port or the motor/blower housing space.
      • Clear the outer battery pack floor. Use warning cleansing across the battery pack connector pins the place the battery contacts with the motor/blower unit or wire. Guarantee this space and the pins are totally dry earlier than subsequent use or storage.
      • Clear the respiration tube by wiping it down. Alternatively, you could immerse the elastomeric respiration tube within the cleansing resolution.
    4. Disinfect the outer surfaces of the PAPR elements by wiping with disinfectant together with motor/blower, battery pack, respiration tube, and waist belt with a clear, delicate material dampened with the suitable disinfectant cleaners beneficial or permitted by the producer. Comply with the person directions for the chosen disinfectants. Warning: By no means soak, dip, or immerse the motor/blower meeting or battery pack in disinfectant.
      • Along with the disinfection options described above, a research of disinfectants towards coronavirus 229E discovered a number of that had been efficient after a 1-minute contact time; these included sodium hypochlorite (at a free chlorine focus of 1,000 ppm and 5,000 ppm), 70% ethyl alcohol.12
    5. Rinse totally, wiping every element with a clear, delicate material dampened with contemporary water warmed to a temperature of roughly 43°C (120°F). Dry totally earlier than use or storage.
      • Permit the respiration tube to fully air dry previous to reuse or storage. Air dry in an uncontaminated environment, temperature to not exceed 43°C (120°F). Alternately, dry by connecting to the motor/blower unit and use it to power air by the tube till dry. Any remaining moisture may contribute to pathogen development or sustainability.
    6. Examine and restore or exchange broken elements (facepiece/headgear, respiration tube, blower, belts) following PAPR producer’s directions.
    7. Retailer elements in a clear, dry location away from contamination. Alternatively, reassemble the PAPR as described within the producer’s person directions, and retailer it in order that it’s prepared for reuse in a clear, dry location away from contamination.

PAPR elements could grow to be broken or deteriorated with extended or prolonged use of disinfecting merchandise. Competent, educated workers should examine the elements of their PAPR following every disinfection and previous to re-use of elements. Moreover, the person ought to all the time examine the elements of their PAPR prior to every use and report any broken elements. Broken elements needs to be repaired or changed based on person directions.

Suggestions from current analysis research and producer stories

Alternate cleansing and disinfection procedures have been studied and located to be usually efficient to be used throughout a pandemic.12 13 Procedures had been used to wash and disinfect elements inoculated with H1N1 influenza A/PR/8/34 (ATCC VR-1469).

  • PAPR blowers, batteries, hoods/helmets, respiration tubes, and belts had been manually cleaned with 0.5% Neutrawash and subsequently disinfected with PDI SaniCloth™ wipes.
  • PAPR elements had been alternately contaminated then cleaned and disinfected dozens of time. A sponge dampened with cleaning soap and water was used to first clear the PAPR hoods and blower items adopted by wiping with a disinfecting wipe. The wipe used was PDI™ Tremendous SaniCloth™.
  • Every PAPR element aside from the filter/cartridge was wiped with an autoclavable sponge moistened with a 42°C, 0.5% Neutrawash detergent resolution and subsequently wiped with one other autoclavable sponge soaked in 42°C water solely to take away any detergent.
  • PAPRs had been then wiped with a Tremendous SaniCloth™ and allowed to dry for 2 minutes. Particular protocols are described within the referenced paperwork regarding cleansing and disinfection of PAPR elements aside from the filter/cartridge.

Whereas these strategies have been demonstrated to be efficient at disinfecting PAPRs, warning needs to be used as some producers have reported that PDI™ AF3 Saniwipes can harm some PAPR elements. The chemical substances in them trigger crazing (a speedy and sever embrittlement of plastics). Chemical compatibility for PAPR elements will not be properly understood. These compounds are known as quaternary ammonium compounds, which PAPR producers strongly suggest needs to be prevented. These disinfectants have been proven to be incompatible with some supplies and wouldn’t have confirmed efficacy towards all microorganisms.11

If following these procedures and making use of them to filter cartridges during times when provides are restricted or not out there, excessive care should be taken to forestall cleansing and disinfectant contact with the filter media. Exterior surfaces of filters cartridges needs to be rigorously wiped, not dipped, soaked, or submerged when making use of the cleansing and disinfectant options.

Practices not permitted by the producer can improve the chance and uncertainty of re-using broken or degraded elements. This should be balanced towards different out there HCP safety choices to maintain efficient HCP safety and affected person care when provides are restricted or not out there.

Modified procedures used throughout emergencies, together with alternate cleansing and disinfection practices, needs to be documented and evaluated ceaselessly all through the disaster operation.


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4OSHA 29CFR1910.134. Accessible from: icon

5OSHA 1910.134 App B-2 Respirator Cleansing Procedures (Obligatory). Accessible from: icon

6NIOSH [2013]. Getting Optimum Efficiency from a Powered Air-purifying Respirator (PAPR) Will depend on the Situation of its Battery! U.S. Division of Well being and Human Companies, Facilities for Illness Management and Prevention, DHHS (NIOSH) Publication 2013-146, icon

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11Rutala WA, Weber DJ [2019]. Healthcare An infection Management Practices Advisory Committee. Guideline for Disinfection and Sterilization in Healthcare Services, 2008.

12Lawrence C, Harnish DA, Sandoval-Powers M, Mills D, Bergman M, Heimbuch BK [2017]. Evaluation of half-mask elastomeric respirator and powered air-purifying respirator reprocessing for an influenza pandemic. Am J Infect Management, 45(12):1324-1330.

13Utilized Analysis Associates, Inc. [2019]. Analysis to Mitigate a Scarcity of Respiratory Safety Gadgets Throughout Public Well being Emergencies. Contract # HHSF22321400158C. Accessible from: icon

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