（地 26）（健Ⅱ18）
令和２年４月８日

都道府県医師会
担 当 理 事 殿
日本医師会感染症危機管理対策室長
釜 萢
敏

Ｎ９５マスクについて

今般、厚生労働省新型コロナウイルス感染症対策推進本部より各都道府県等衛
生 主 管 部 (局 )に 対 し て 、事 務 連 絡「 Ｎ ９ ５ マ ス ク に つ い て（ 依 頼 )」の 発 出 が あ り 、本会に対しても周知方依頼がありました。
厚生労働省においては、Ｎ９５マスクで供給不足が生じている状況に対応する
ため、Ｎ９５マスクの再利用に関する海外の知見を収集しており、知見に基づく方針について近日中にとりまとめる予定とのことであります。
本事務連絡は、Ｎ９５マスクの供給については、当面のところ増加の見通しが立たないことから、廃棄について慎重にご検討いただくことについて周知を依頼するものです。
つ き ま し て は 、貴 会 に お か れ ま し て も 、本 件 に つ い て ご 了 知 い た だ く と と も に 、貴会管下関係医療機関に対する周知につき、ご高配の程お願い申し上げます。
追って、使用後のＮ９５マスクの廃棄を猶予される際には、その感染性についてもご留意頂きたく、保管場所や保管方法についてもご配慮を頂きたく、どうぞよろしくお願い申し上げます。

事

務

連

絡

令和２年４月７日
公益社団法人

日本医師会

御中

厚生労働省新型コロナウイルス感染症対策推進本部

Ｎ９５マスクについて（依頼）

現在、Ｎ９５マスクについては、医療機関において使用されているところですが、供給不足が生じている状況です。このことに対応するため、厚生労働省ではＮ９５マスクの再利用に関する海外の知見を収集しているところです（別添参照）。これらの知見に基づく方針については、近日中に取りまとめる予定です。
今後のＮ９５マスクの供給については、当面のところ増加の見通しがたたないことから、廃棄について慎重にご検討いただくよう、新型コロナウイルス感染症の治療等に対応いた
だいている貴下団体会員等に対する周知方よろしくお取り計らい願います。

事 務 連 絡
令和２年４月７日
都 道 府 県
各保健所設置市
特別衛生主管部（局） 御中区

厚生労働省新型コロナウイルス感染症対策推進本部

Ｎ９５マスクについて（依頼）
現在、Ｎ９５マスクについては、医療機関において使用されているところですが、供給不足が生じている状況です。このことに対応するため、厚生労働省ではＮ９５マスクの再利用に関する海外の知見を収集しているところです（別添参照）。これらの知見に基づく方針については、近日中に取りまとめる予定です。
今後のＮ９５マスクの供給については、当面のところ増加の見通しがたたな
いことから、廃棄について慎重にご検討いただくよう、管内医療機関に周知をお願いいたします。

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別添
Coronavirus Disease 2019 (COVID-19)

Decontamination and Reuse of Filtering Facepiece
Respirators
Disposable filtering facepiece respirators (FFRs) are not approved for routine decontamination and reuse as standardof care. However, FFR decontamination and reuse may need to be considered as a crisis capacity strategy to ensure
continued availability. Based on the limited research available, ultraviolet germicidal irradiation, vaporous hydrogen
peroxide, and moist heat showed the most promise as potential methods to decontaminate FFRs. This document
summarizes research about decontamination of FFRs before reuse.

Introduction
Reusing disposable filtering facepiece respirators (FFRs) has been suggested as a contingency capacity strategy toconserve available supplies for healthcare environments during a pandemic. Strategies for FFR extended use and reuse(without decontamination of the respirator) are currently available from CDC’s National Institute for Occupational Safety
and Health (NIOSH).
The surfaces of an FFR may become contaminated while filtering the inhalation air of the wearer during exposures topathogen-laden aerosols. The pathogens on the filter materials of the FFR may be transferred to the wearer upon contact
with the FFR during activities such as adjusting the FFR, improper doffing of the FFR, or when performing a user-seal checkwhen redoffing a previously worn FFR. A study evaluating the persistence of SARS-CoV-2 (the virus that causes COVID-19)
on plastic, stainless steel, and carboard surfaces showed that the virus is able to survive for up to 72-hours [1]. One
strategy to mitigate the contact transfer of pathogens from the FFR to the wearer during reuse is to issue five respirators
to each healthcare worker who may care for patients with suspected or confirmed COVID-19. The healthcare worker will
wear one respirator each day and store it in a breathable paper bag at the end of each shift. The order of FFR use should
be repeated with a minimum of five days between each FFR use. This will result in each worker requiring a minimum of
five FFRs, providing that they put on, take off, care for them, and store them properly each day. Healthcare workers
should treat the FFRs as though they are still contaminated and follow the precautions outlined in our reuserecommendations. If supplies are even more constrained and five respirators are not available for each worker who
needs them, FFR decontamination may be necessary.
Decontamination and subsequent reuse of FFRs should only be practiced as a crisis capacity strategy. At present, FFRs are
considered one time use and there are no manufacturer authorized methods for FFR decontamination prior to reuse. On
March 28, 2020, FDA issued an Emergency Use Authorization (EUA) permitting the Battelle Decontamination System  atBattelle Memorial Institute to be authorized for use in decontaminating “compatible N95 respirators.” The FDA website 
should be checked to determine if other EUAs have been issued since the posting of this crisis capacity strategy guidance.
Only respirator manufacturers can reliably provide guidance on how to decontaminate their specific models of FFRs. In
absence of manufacturer’s recommendations, third parties may also provide guidance or procedures on how todecontaminate respirators without impacting respirator performance. Decontamination might cause poorer fit, filtration
efficiency, and breathability of disposable FFRs as a result of changes to the filtering material, straps, nose bridge material,or strap attachments of the FFR. CDC and NIOSH do not recommend that FFRs be decontaminated and then reused as
standard care. This practice would be inconsistent with their approved use, but we understand in times of crisis, thisoption may need to be considered when FFR shortages exist.
An effective FFR decontamination method should reduce the pathogen burden, maintain the function of the FFR, andpresent no residual chemical hazard. The filter media in NIOSH-approved respirators varies by manufacturer. The abilityof the respirator filter media to withstand cleaning and disinfection are not NIOSH performance requirements. The

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NIOSH’s National Personal Protective Technology Laboratory (NPPTL) and other researchers have investigated the impact
of various decontamination methods on filtration efficiency, facepiece fit of FFRs, and the ability to reduce viable virus orbacteria on the FFRs. This research is summarized below.

Crisis Standards of Care Decontamination
Recommendations
Because ultraviolet germicidal irradiation (UVGI), vaporous hydrogen peroxide (VHP), and moist heat showed the mostpromise as potential methods to decontaminate FFRs, researchers, decontamination companies, healthcare systems, orindividual hospitals should focus current efforts on these technologies. Specifically, the effectiveness of using thesemethods should be explored further with specific FFR models based on the manufacturers’ support to better understandthe impact on the respirator performance, including filtration and fit. The respirator manufacturer should be consulted
about the impact of the method on their respirators prior to considering the use of any method.
When information from the manufacturer or a third-party is available showing that respirators can be successfully
decontaminated without impacting respirator performance, then FFRs decontaminated following those recommendations
can be worn for any patient care activities.
In the absence of guidance or when information is available that a respirator cannot be decontaminated without
negatively impacting the performance, respirators may still be decontaminated. However, given the uncertainties on theimpact of decontamination on respirator performance, these FFRs should not be worn by HCPs when performing orpresent for an aerosol-generating procedure.
No current data exists supporting the effectiveness of these decontamination methods specifically against SARS-CoV-2 onan FFR. Other pathogens may also be present on FFRs and there is only limited data available for other pathogens.
Further work is needed to assure SARS-CoV-2 and other pathogens are inactivated. Therefore, even after
decontamination, these FFRs should be handled carefully.
HCPs should take the following precautionary measures prior to using a decontaminated FFR:
• Clean hands with soap and water or an alcohol-based hand sanitizer before and after touching or adjusting the FFR.
• Avoid touching the inside of the FFR.
• Use a pair of clean (non-sterile) gloves when donning and performing a user seal check.
• Visually inspect the FFR to determine if its integrity has been compromised.
• Check that components such as the straps, nose bridge, and nose foam material did not degrade, which can affect
the quality of the fit, and seal.
• If the integrity of any part of the FFR is compromised, or if a successful user seal check cannot be performed, discard
the FFR and try another FFR.
• Users should perform a user seal check immediately after they don each FFR and should not use an FFR on which
they cannot perform a successful user seal check.
Table 1 provides a summary of the crisis standards of care decontamination recommendations.
Table 1. Summary of crisis standards of care decontamination recommendations
Manufacturer or
third-party guidanceor procedures

Recommendation for use

Methodavailable

after decontamination

Ultraviolet

Yes

Can be worn for any patientgermicidal
irradiation(UVGI)

care activities

Additional use considerations• Clean hands with soap and wateror an alcohol-based hand sanitizer
before and after touching or
adjusting the FFR.

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Manufacturer or
third-party guidance
Methodor procedures

Recommendation for use

available

after decontamination

Additional use considerations• Avoid touching the inside of the

Vaporous

FFR.

hydrogen• Use a pair of clean (non-sterile)peroxide

gloves when donning and(VHP)

performing a user seal check.
• Visually inspect the FFR to

Moist heat

determine if its integrity has been
UltravioletNocompromised.

Can be worn for patient caregermicidal

activities except whenirradiation

performing or present for an(UVGI)

aerosol generating procedure• Check that components such as thestraps, nose bridge, and nose foammaterial did not degrade, which
can affect the quality of the fit, andseal.

Vaporoushydrogen• If the integrity of any part of the
FFR is compromised, or if aperoxide(VHP)

successful user seal check cannot
be performed, discard the FFR and

Moist heat

try another FFR.
• Users should perform a user seal

check literature
immediately
they donTable 2 provides a summary of the decontamination methods evaluated in the referenced
andafterthe reported
each
FFR
and
shouldnot
use aneffect of each method on FFR performance.
FFR on which they cannot perform
Table 2. Summary of the decontamination method and effect on FFR performancea successful user seal check.

MethodTreatment level

FFR filtration
performance

FFR fitperformance

Other
observations

References

Vaporous

Battelle report: Bioquell

PassedFFR fit was

Degradation

3, 4hydrogenperoxide

Clarus C HPV generator: The
HPV cycle included a 10 min

shown to beunaffected forof straps after
30 cycles(VHP)

conditioning phase, 20 min

up to 20 VHP(Battellegassing phase at 2 g/min, 150

treatments

report)min dwell phase at 0.5 g/min,and 300 min of aeration.

cycles using ahead form

Bergman et. al.: Room BioDecontamination Service(RBDS™, BIOQUELL UK Ltd,
Andover, UK), which utilizes
four portable modules: theClarus® R HPV generator(utilizing 30% H2O2), theClarus R20 aeration unit, an
instrumentation module anda control computer. Roomconcentration = 8 g/m3, 15
min dwell, 125 min total cycle
time.

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FFR filtration

FFR fit

Other

MethodTreatment level

performance

performanceobservations

Ultraviolet

0.5–950 J/cm2

Passed

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References

90–100%2, 3, 7, 8, 9,

germicidal

passing rate10

irradiation

after 3 cycles(UVGI)

depending on
model

Microwave

1100–1250 W microwave

All models

95–100%

generatedmodels (range: 40 sec to 2

passed filtrationpassing rate

steam

min)

evaluation for 1

after 3 and 20

or 20 treatment
cycles as per test

cycles for allmodels tested

9, 10, 14

Microwave
steam bags

1100 W, 90 sec (bags filledwith 60 mL tap water)

PassedNot evaluated15

Moist heat15 min–30 min (60°C, 80%

6 of 6 models

Passed3, 9, 10incubation

RH)

passed after 3cycles ofcontamination

Liquid1 sec to 30 min (range: 3–6%)

PassedNot evaluated3, 7Ethylene

1 hour at 55°C; conc. range:

PassedNot evaluated

2, 3, 7oxide

725–833/Lhydrogenperoxide

Table 3 provides a summary of the decontamination methods used, the treatment levels assessed, the microbes tested,
and the antimicrobial efficacy as reported in the literature.
Table 3. Summary of decontamination method antimicrobial efficacy
Antimicrobial
MethodTreatment level

Microbe tested

efficacy

References

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Antimicrobial
MethodTreatment level

Microbe tested

efficacy

References

Vaporous

Battelle report: Bioquell Clarus C HPV

3, 4, 6

generator: The HPV cycle included a 10

peroxide

min conditioning phase, 20 min gassing

Geobacillus
stearothermophilus
spores>99.999%hydrogen(VHP)

phase at 2 g/min, 150 min dwell phase at

T1, T7, and phi-6

0.5 g/min, and 300 min of aeration.

bacteriophages

99.9% for all
tested viruses

12, 13, 14

99.9%

14

Bergman et. al.: Room BioDecontamination Service (RBDS™,BIOQUELL UK Ltd, Andover, UK), which
utilizes four portable modules: theClarus® R HPV generator (utilizing 30%
H2O2), the Clarus R20 aeration unit, an
instrumentation module and a control
computer. Room concentration = 8 g/m3,
15 min dwell, 125-min total cycle time.
Kenney personal communication:
Bioquell BQ-50 generator: The HPV cycle
included a 10 minute conditioning phase,
30–40 min gassing phase at 16 g/min, 25
min dwell phase, and a 150 min aeration
phase.
Ultraviolet
germicidal

0.5–950 J/cm2

Influenza A (H1N1)
Avian influenza A virus

irradiation(H5N1),(UVGI)

low pathogenic
Influenza A (H7N9),
A/Anhui/1/2013
Influenza A (H7N9),
A/Shanghai/1/2013
MERS-CoVSARS-CoV
H1N1
Influenza A/PR/8/34
MS2 bacteriophage

Microwave

1100–1250 W microwave models (range:

H1N1 influenza

generatedsteam

40 sec to 2 min)

A/PR/8/34

Microwave
steam bags

1100 W, 90 sec (bags filled with 60 mL tap
water)

MS2 bacteriophage

99.9%

15

Moist heat

15–30 min (60°C, 80% RH)

H1N1 influenza

99.99%

14

incubation
Liquidhydrogen

A/PR/8/34
1 sec to 30 min (range: 3–6%)

Not evaluatedNot evaluated

1 hour at 55°C; conc. range: 725–833 mg/L

Not evaluatedNot evaluatedperoxide
Ethyleneoxide

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Vaporous hydrogen peroxide, ultraviolet germicidal
irradiation, and moist heat are the most promising
FFR decontamination methods
Vaporous hydrogen peroxide, ultraviolet germicidal irradiation, and moist heat are the most promising decontamination
methods. If FFR decontamination is considered, these methods do not appear to break down filtration or compromise the
FFR; however, many of these methods can only be used for limited times.

Vaporous hydrogen peroxide
Investigations into VHP decontamination of FFRs provides evidence of minimal effect to filtration and fit while
demonstrating 99.9999% efficiency in killing bacterial spores. VHP did not reduce the filtration performance of the ten
N95 FFR models tested while showing a 6-log reduction in Geobacillus stearothermophilus spores [2-4]. In a report
prepared by Battelle Memorial Institute, the 3M 1860 FFR was shown to maintain filtration performance for 50 treatment
cycles of VHP, also referred to as HPV by some decontamination system manufacturers, using the Clarus® R HPVgenerator form Bioquell (utilizing 30% H2O2). Additionally, FFR fit was shown to be unaffected for up to 20 VHP treatments
cycles using NPPTL’s Static Advanced Headform [4, 5]. Strap degradation occurred after 20 treatment cycles. Kenney et al.,co-contaminated 3M 1870 FFRs with three bacteriophages, T1, T7, and Phi 6, and decontaminated the FFRs using VHP
generated from the Bioquell’s BQ-50 system. The VHP treatment was shown inactivate >99.999% of all phages which was
below the limit of detection [6]. Viscusi et al. found that 9 FFR models (three particulate N95, three surgical N95 FFRs andthree P100) exposed to one cycle of VHP treatment using the STERRAD 100S H2O2 Gas Plasma Sterilizer (Advanced
Sterilization Products, Irvine, CA) had filter aerosol penetration and filter airflow resistance levels similar to untreatedmodels; however, Bergman et al. found that three cycles of VHP treatment using the STERRAD 100S H2O2 Gas Plasma
Sterilizer negatively affected filtration performance [2, 3]. Bergman et al. measured acceptable filtration performance for
six FFR models (three particulate and three surgical FFRs) that received three cycles of VHP treatment using the Clarus® R
HPV generator (utilizing 30% H2O2) [3]. VHP is a promising method with a potential for high capacity throughput, but
certain VHP systems, such as the Clarus® R HPV generator, may be more compatible with FFR decontamination.

Ultraviolet germicidal irradiation
UVGI is a promising method but the disinfection efficacy is dependent on dose. Not all UV lamps provide the same
intensity thus treatment times would have to be adjusted accordingly. Moreover, UVGI is unlikely to kill all the viruses andbacteria on an FFR due to shadow effects produced by the multiple layers of the FFR’s construction. Acceptable filtration
performance was recorded for eleven FFR models exposed to various UV doses ranging from roughly 0.5–950 J/cm2 andUVGI was shown to have minimal effect on fit [2, 3, 7, 8, 9, 10]. Heimbuch et al. tested filtration and fit of 15 FFRs andfound no adverse effects to FFR performance [11]. Lindsley et al. reported a reduction of the durability of materials of the
FFRs for doses ranging from 120–950 J/cm2; however, an approximate inactivation of 99.9% of bacteriophage MS2, a nonenveloped virus, and H1N1 influenza A/PR/8/34 were achieved with much lower doses of approximately 1 J/cm2 [12–14].
Heimbuch et al. tested the performance of 1 J/cm2 of UVGI against Influenza A (H1N1), Avian influenza A virus (H5N1),
Influenza A (H7N9) A/Anhui/1/2013, Influenza A (H7N9) A/Shanghai/1/2013, MERS-CoV, and SARS-CoV and reported virus
inactivation from 99.9% to greater than 99.999% [11]. UVGI is harmful. Proper precautions are required to avoid UVGI
exposure to skin or the eyes.

Moist heat
Moist heat, consisting of 60°C and 80% RH caused minimal degradation in the filtration and fit performance of the tested
FFRs [3, 9, 10]. Heimbuch et al. disinfected FFRs contaminated with H1N1 using moist heat, of 65°C and 85% RH, andachieved a minimal of 99.99% reduction in virus [14]. One limitation of the moist heat method is the uncertainty of thedisinfection efficacy for various pathogens.

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Steam treatment and liquid hydrogen peroxide arepromising methods with some limitations
Steam treatment
Steam treatment may be a suitable approach for decontaminating FFRs. The limited number of studies for steam reportminimal effect on FFR filtration and fit performance and a minimum 99.9% reduction in H1N1 and bacteriophage MS2 [14,15]. Fisher et al. used microwave steam bags, designed for disinfecting infant feeding equipment, to decontaminate six
FFR models and achieved 99.9% inactivation of MS2 bacteriophage. Filtration performance of all tested FFRs scored above
NIOSH certification requirements. Three FFRs were further evaluated for three cycles of steam exposure anddemonstrated no change in filtration performance [15]. Bergman et al. also demonstrated acceptable filtration
performance after three cycles of exposure to microwave generated steam [3]. Microwave generated steam had little
effect on FFR fit after exposure to up to three cycles of steam [9, 10]. Using microwaves to produce steam todecontaminate FFRs is not without limitations. Not all microwaves are constructed the same and some are more powerfulthan others. The effect of higher power microwaves on FFRs is unknown. Furthermore, the metal nosebands of FFRs may
cause arcing, sparks inside the microwave oven, during exposure to microwaves.

Liquid hydrogen peroxide
Liquid hydrogen peroxide showed no effect of FFR filtration performance [3, 7]. Bergman et al. evaluated six FFRs forfiltration performance after a 30-minute submersion in 6% hydrogen peroxide. All six FFR models tested demonstrated nochanges in filter performance after three cycles of decontamination. FFR fit and disinfection efficacy were not assessed forthis method.
Table 4 provides a summary of the decontamination methods evaluated for each FFR model.
Table 4. Decontamination methods evaluated for each FFR model
FFR Model

Type

VHP

UVGI

EtO

Steam

Moist heat

Hydrogen peroxide

3M 1860

N95

x

x

x

x

x

x

3M 1870

N95

x

x

x

x

x

x

3M 8000

N95

x

x

x

x

x

x

3M 8210

N95

x

x

x

x

x

x

3M 9210N95

x

3M Vflex 1805

N95

xAlpha protech

N95x

Cardinal Health

N95

Gerson 1730

N95

Kimberly Clark PFR-95

N95

x

x

Moldex 1512

N95

x

Moldex 1712

N95

x

x
x
x

x

x

x

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FFR Model

Type

VHP

UVGI

EtO

Steam

Moist heat

Moldex 2200

N95

x

x

x

x

x

Moldex 2201

N95

x

x

x

x

x

Precept 65-3395

N95

x

Prestige Ameritech RP88020

N95x

Sperian HC-NB095

N95x

Sperian HC-NB295

N95

x

U.S. Safety AD2N95A

N95

x

U.S. Safety AD4N95A

N95

x

3M 8293

P100

x

x

Moldex 2360

P100

x

x

North 8150

P100

x

x

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Hydrogen peroxidexx

Decontamination methods that changed FFR
performance or function
Autoclaving and the use of disinfectant wipes are not recommended as crisis strategies as they may alter FFR
performance.

Autoclave, dry heat, isopropyl alcohol, soap, dry microwave
irradiation and bleachDecontamination using an autoclave, 160°C dry heat, 70% isopropyl alcohol, microwave irradiation and soap and water
caused significant filter degradation to both FFRs and particle penetration levels did not meet the levels that NIOSH would
allow for approval. Decontamination with bleach caused slight degradation in filtration performance and created an odor
that would not be suitable for use [2, 7].

Disinfectant wipes
Heimbuch et al. evaluated biological decontamination efficacy and filtration penetration following aerosol exposure of
mucin or viable Staphylococcus aureus [18]. Following aerosol exposure, respirators were cleaned with three types ofwipes: hypochlorite, benzalkonium chloride (BAC), or nonantimicrobial. Particle penetration following cleaning yieldedmean values <5%. The highest penetrations were observed in FFRs cleaned with BAC wipes. The BAC wipe caused one
sample of FFRs to exceed 5% penetration. Filter penetration following various decontamination methods was shown inthis study to vary based on the decontamination method and the model of FFR.

Ethylene oxide as a promising method with serious
limitation
Ethylene oxide is not recommended as a crisis strategy as it may be harmful to the wearer.

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Ethylene oxide (EtO) was shown to not harm filtration performance for the nine tested FFR models [2, 3, 7]. All tests wereconducted for one hour at 55˚C with EtO gas concentrations ranging from 725 to 833 g/L. Six models that were exposedto three cycles of 736 mg/L EtO all passed the filtration performance assessment [3]. Data is not available for the effectthat EtO treatment may have on FFR fit. However, EtO treatment does not cause visible physical changes to theappearance of FFRs [2, 3]. A serious concern about using EtO for decontamination of large numbers of FFRs is throughput,
since relatively long aeration cycles are needed to ensure removal of highly toxic EtO gas [2]. Any use of ethylene oxide(EtO) should be accompanied by studies to ensure no off-gassing into the breathing zone of the wearer as EtO is
carcinogenic and teratogenic. Chronic inhalation of EtO has been linked to neurologic dysfunction and may cause otherharmful effects to the wearer [16]. EtO should be used in accordance with Occupational Safety and Health Administration
standard 29 CFR 1910.1047 [17].

Other methods for consideration which have not beentestedHospitals may have other decontamination capabilities on-hand that may be feasible. For example, photodynamic
inactivation of pathogens using methylene blue plus visible light exposure is used to treat blood products and there isinterest in using the method to decontaminate PPE. There is currently no data to evaluate the effect of this method on
FFR filtration and fit [19].

References
1. van Doremalen, N., et al., Aerosol and Surface Stability of SARS-CoV-2 as Compared with SARS-CoV-1. J New England
Journal of Medicine, 2020.
2. Viscusi, D.J., et al., Evaluation of five decontamination methods for filtering facepiece respirators. Annals ofoccupational hygiene, 2009. 53(8): p. 815-827.
3. Bergman, M., et al., Evaluation of Multiple (3-Cycle) Decontamination Processing for Filtering Facepiece Respirators.
Journal of Engineered Fibers and Fabrics, 2010. 5(4): p. 33-41.
4. Battelle. Final Report for the Bioquell Hydrogen Peroxide Vapor (HPV) Decontamination for Reuse of N95 Respirators.
2016; Available from: https://www.fda.gov/emergency-preparedness-and-response/mcm-regulatoryscience/investigating-decontamination-and-reuse-respirators-public-health-emergencies  .
5. Bergman, M.S., et al., Development of an advanced respirator fit-test headform. Journal of Occupational andEnvironmental Hygiene, 2014. 11(2): p. 117-125.
6. Kenney, Patrick, et al. Hydrogen Peroxide Vapor sterilization of N95 respirators for reuse. medRxiv (2020).
7. Viscusi, D.J., King, W.P., Shaffer, R.E., Effect of decontamination on the filtration efficiency of two filtering facepiece

respirator models. Journal of the International Society for Respiratory Protection, 2007. 24: p. 93-107.
8. Lindsley, W.G., et al., Effects of ultraviolet germicidal irradiation (UVGI) on N95 respirator filtration performance andstructural integrity. Journal of Occupational and Environmental Hygiene 2015. 12(8): p. 509-517.
9. Bergman, M., et al., Impact of Three Cycles of Decontamination Treatments on Filtering Facepiece Respirator Fit.
Journal of the International Society for Respiratory Protection, 2011. 28(1): p. 48-59.
10. Viscusi, D.J., et al., Impact of three biological decontamination methods on filtering facepiece respirator fit, odor,

comfort, and donning ease. Journal of Occupational and Environmental Hygiene, 2011. 8(7): p. 426-36.
11. Heimbuch, B.K. and D. Harnish. Research to Mitigate a Shortage of Respiratory Protection Devices During Public
Health Emergencies. 2019; Available from: https://www.ara.com/news/ara-research-mitigate-shortage-respiratoryprotection-devices-during-public-health-emergencies 
12. Fisher, E.M. and R.E. Shaffer, A method to determine the available UV-C dose for the decontamination of filtering

facepiece respirators. Journal of Applied Microbiology, 2011. 110(1): p. 287-295.
13. Mills, D., et al., Ultraviolet germicidal irradiation of influenza-contaminated N95 filtering facepiece respirators.
American Journal of Infection Control, 2018. 46(7): p. e49-e55.
14. Heimbuch, B.K., et al., A pandemic influenza preparedness study: use of energetic methods to decontaminate

filtering facepiece respirators contaminated with H1N1 aerosols and droplets. American Journal of Infection Control,
2011. 39(1): p. e1-e9.

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15. Fisher, E.M., J.L. Williams, and R.E. Shaffer, Evaluation of microwave steam bags for the decontamination of filtering

facepiece respirators. PLoS One, 2011. 6(4).
16. Rutala, W.A. and D.J. Weber. Guideline for disinfection and sterilization in healthcare facilities, 2008. 2008; Available
from: https://www.cdc.gov/infectioncontrol/guidelines/disinfection/.
17. Occupational Safety and Health Administration. Ethylene oxide: 29 CFR 1910.1047
18. Heimbuch, B.K., et al., Cleaning of filtering facepiece respirators contaminated with mucin and Staphylococcus

aureus. American Journal of Infection Control, 2014. 42(3): p. 265-270.
19. Eickmann, M., et al., Inactivation of Ebola virus and Middle East respiratory syndrome coronavirus in plateletconcentrates and plasma by ultraviolet C light and methylene blue plus visible light, respectively. Transfusion, 2018.
58(9): p. 2202-2207.
20. 3M. Disinfection of Filtering Facepiece Respirators. Technical Bulletin 2020; Available from:https://multimedia.3m.com/mws/media/1816576O/disinfection-of-disposable-respirators-technical-bulletin.pdf. 

Other resources
Lowe, J.J. N95 Filtering Facemask Respirator Ultraviolet Germicidal Irradiation (UVGI) Process for Decontamination andReuse. 2020; Available from: https://www.nebraskamed.com/sites/default/files/documents/covid-19/n-95-deconprocess.pdf   .
Page last reviewed: April 1, 2020
Content source: National Center for Immunization and Respiratory Diseases (NCIRD), Division of Viral Diseases

https://www.cdc.gov/coronavirus/2019-ncov/hcp/ppe-strategy/decontamination-reuse-respirat... 2020/04/07