From “don, doff, and discard” to “don, doff, and decontaminate” – determination of filtering facepiece respirator and surgical mask integrity and inactivation of a SARS-CoV-2 surrogate and a small non-enveloped virus following multiple-cycles of vaporised hydrogen peroxide, ultraviolet germicidal irradiation, and dry heat decontamination

ABSTRACTBackgroundAs the SARS-CoV-2 pandemic accelerates, the supply of personal protective equipment remains under strain. To combat shortages, re-use of surgical masks and filtering facepiece respirators has been recommended. Prior decontamination is paramount to the re-use of these typically single-use only items and, without compromising their integrity, must guarantee inactivation of SARS-CoV-2 and other contaminating pathogens.AimWe provide information on the effect of time-dependent passive decontamination at room temperature and evaluate inactivation of a SARS-CoV-2 surrogate and a non-enveloped model virus as well as mask and respirator integrity following active multiple-cycle vaporised hydrogen peroxide (VHP), ultraviolet germicidal irradiation (UVGI), and dry heat (DH) decontamination.MethodsMasks and respirators, inoculated with infectious porcine respiratory coronavirus or murine norovirus, were submitted to passive decontamination or single or multiple active decontamination cycles; viruses were recovered from sample materials and viral titres were measured via TCID50 assay. In parallel, filtration efficiency tests and breathability tests were performed according to EN standard 14683 and NIOSH regulations.Results and DiscussionInfectious porcine respiratory coronavirus and murine norovirus remained detectable on masks and respirators up to five and seven days of passive decontamination. Single and multiple cycles of VHP-, UVGI-, and DH were shown to not adversely affect bacterial filtration efficiency of masks. Single- and multiple UVGI did not adversely affect respirator filtration efficiency, while VHP and DH induced a decrease in filtration efficiency after one or three decontamination cycles. Multiple cycles of VHP-, UVGI-, and DH slightly decreased airflow resistance of masks but did not adversely affect respirator breathability. VHP and UVGI efficiently inactivated both viruses after five, DH after three, decontamination cycles, permitting demonstration of a loss of infectivity by more than three orders of magnitude. This multi-disciplinal approach provides important information on how often a given PPE item may be safely reused.

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“Don, doff, discard” to “don, doff, decontaminate”—FFR and mask integrity and inactivation of a SARS-CoV-2 surrogate and a norovirus following multiple vaporised hydrogen peroxide-, ultraviolet germicidal irradiation-, and dry heat decontaminations

PLoS ONE ◽

10.1371/journal.pone.0251872 ◽

2021 ◽

Vol 16 (5) ◽

pp. e0251872

Author(s):

Louisa F. Ludwig-Begall ◽

Constance Wielick ◽

Olivier Jolois ◽

Lorène Dams ◽

Ravo M. Razafimahefa ◽

...

Keyword(s):

Hydrogen Peroxide ◽

Filtration Efficiency ◽

Murine Norovirus ◽

Ultraviolet Germicidal Irradiation ◽

Dry Heat ◽

Multiple Cycle ◽

Single Use ◽

Multiple Cycles ◽

Respiratory Coronavirus ◽

Porcine Respiratory

Background As the SARS-CoV-2 pandemic accelerates, the supply of personal protective equipment remains under strain. To combat shortages, re-use of surgical masks and filtering facepiece respirators has been recommended. Prior decontamination is paramount to the re-use of these typically single-use only items and, without compromising their integrity, must guarantee inactivation of SARS-CoV-2 and other contaminating pathogens. Aim We provide information on the effect of time-dependent passive decontamination (infectivity loss over time during room temperature storage in a breathable bag) and evaluate inactivation of a SARS-CoV-2 surrogate and a non-enveloped model virus as well as mask and respirator integrity following active multiple-cycle vaporised hydrogen peroxide (VHP), ultraviolet germicidal irradiation (UVGI), and dry heat (DH) decontamination. Methods Masks and respirators, inoculated with infectious porcine respiratory coronavirus or murine norovirus, were submitted to passive decontamination or single or multiple active decontamination cycles; viruses were recovered from sample materials and viral titres were measured via TCID50 assay. In parallel, filtration efficiency tests and breathability tests were performed according to EN standard 14683 and NIOSH regulations. Results and discussion Infectious porcine respiratory coronavirus and murine norovirus remained detectable on masks and respirators up to five and seven days of passive decontamination. Single and multiple cycles of VHP-, UVGI-, and DH were shown to not adversely affect bacterial filtration efficiency of masks. Single- and multiple UVGI did not adversely affect respirator filtration efficiency, while VHP and DH induced a decrease in filtration efficiency after one or three decontamination cycles. Multiple cycles of VHP-, UVGI-, and DH slightly decreased airflow resistance of masks but did not adversely affect respirator breathability. VHP and UVGI efficiently inactivated both viruses after five, DH after three, decontamination cycles, permitting demonstration of a loss of infectivity by more than three orders of magnitude. This multi-disciplinal approach provides important information on how often a given PPE item may be safely reused.

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The use of germicidal ultraviolet light, vaporised hydrogen peroxide and dry heat to decontaminate face masks and filtering respirators contaminated with an infectious norovirus

10.1101/2020.09.04.20188250 ◽

2020 ◽

Author(s):

Constance Wielick ◽

Louisa Fiona Ludwig-Begall ◽

Lorene Dams ◽

Ravo Michele Razafimahefa ◽

Pierre-Francois Demeuldre ◽

...

Keyword(s):

Hydrogen Peroxide ◽

Ultraviolet Light ◽

Murine Norovirus ◽

Ultraviolet Germicidal Irradiation ◽

Dry Heat ◽

Surgical Masks ◽

Oral Pathogens

In the context of the SARS-CoV-2 pandemic, reuse of surgical masks and filtering facepiece respirators has been recommended. Their reuse necessitates procedures to inactivate contaminating human respiratory and oral pathogens. We previously demonstrated decontamination of masks and respirators contaminated with an infectious SARS-CoV-2 surrogate via ultraviolet germicidal irradiation, vaporised hydrogen peroxide, and use of dry heat. Here, we show that these same methods efficiently inactivate a more resistant, non-enveloped oral virus; decontamination of infectious murine norovirus-contaminated masks and respirators reduced viral titres by over four orders of magnitude on mask or respirator coupons.

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The use of germicidal ultraviolet light, vaporised hydrogen peroxide and dry heat to decontaminate face masks and filtering respirators contaminated with a SARS-CoV-2 surrogate virus

10.1101/2020.06.02.20119834 ◽

2020 ◽

Cited By ~ 1

Author(s):

Louisa F Ludwig-Begall ◽

Constance Wielick ◽

Lorene Dams ◽

Hans Nauwynck ◽

Pierre-Francois Demeuldre ◽

...

Keyword(s):

Heat Treatment ◽

Uv Irradiation ◽

Protective Equipment ◽

Stable Model ◽

Dry Heat ◽

Surgical Masks ◽

Single Use ◽

Dry Heat Treatment ◽

Respiratory Coronavirus ◽

Porcine Respiratory

Background In the context of the ongoing severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic, the supply of personal protective equipment remains under severe strain. To address this issue, re-use of surgical face masks and filtering facepiece respirators has been recommended; prior decontamination is paramount to their re-use. Aim We aim to provide information on the effects of three decontamination procedures on porcine respiratory coronavirus (PRCV)-contaminated masks and respirators, presenting a stable model for infectious coronavirus decontamination of these typically single-use-only products. Methods Surgical masks and filtering facepiece respirator coupons and straps were inoculated with infectious PRCV and submitted to three decontamination treatments, UV irradiation, vaporised H2O2, and dry heat treatment. Viruses were recovered from sample materials and viral titres were measured in swine testicle cells. Findings UV irradiation, vaporised H2O2 and dry heat reduced infectious PRCV by more than three orders of magnitude on mask and respirator coupons and rendered it undetectable in all decontamination assays. Conclusion This is the first description of stable disinfection of face masks and filtering facepiece respirators contaminated with an infectious SARS-CoV-2 surrogate using UV irradiation, vaporised H2O2 and dry heat treatment. The three methods permit demonstration of a loss of infectivity by more than three orders of magnitude of an infectious coronavirus in line with the FDA policy regarding face masks and respirators. It presents advantages of uncomplicated manipulation and utilisation in a BSL2 facility, therefore being easily adaptable to other respirator and mask types.

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Surgical masks decontamination for reuse by members of the public: feasibility study and development of home-based methods

10.21203/rs.3.rs-72875/v1 ◽

2020 ◽

Author(s):

Mun Cheok Hong ◽

Tan Sook Lan ◽

Phua Soo Zeng Fiona ◽

Lim Wei Qi ◽

Pang Shyue Wei ◽

...

Keyword(s):

Hydrogen Peroxide ◽

Staphylococcus Aureus ◽

Ultraviolet Irradiation ◽

Influenza A ◽

H1n1 Influenza ◽

Filtration Efficiency ◽

The Public ◽

Enveloped Virus ◽

Log Reduction ◽

Surgical Masks

Abstract This study aims to propose decontamination methods that are suitable for use by members of the public to cope with the shortage of surgical masks during the current COVID-19 pandemic. 3-ply surgical masks were subjected to different decontamination protocols (heat, chemical, ultraviolet irradiation) to assess their abilities to achieve at least 4-log reduction of two common respiratory pathogens, H1N1 Influenza A virus, a single-stranded RNA enveloped virus similar to SARS-CoV-2 and Staphylococcus aureus, a Gram-positive bacterium that is more resistant to decontamination than single stranded RNA enveloped virus. Decontaminated surgical masks were assessed for differences in breathability, particle filtration efficiency and bacteria filtration efficiency as compared with non-decontaminated masks. The number of decontamination cycles that the 3-ply surgical masks could undergo without significant changes in breathability and filtration efficiencies were also determined. It was found that surgical masks decontaminated by either soaking for 60 min in 0.5% (v/v) aqueous hydrogen peroxide solution, or 30 min of soaking in 0.05% - 0.5% (v/v) aqueous sodium hypochlorite diluted from household bleach or ultraviolet irradiation by a surface dose of 13.5 kJ/m2 were able to achieve at least a 4-log reduction of both Staphylococcus aureus and H1N1 Influenza A virus spiked on surgical mask test swatches. No significant changes in breathability and filtration efficiencies of the surgical masks were observed after ten decontamination cycles of hydrogen peroxide or diluted bleach treatment or 30 cycles of ultraviolet irradiation.

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Reusing and/or reprocessing the N95 face respirator mask or equivalent: An integrative review

Revista Latino-Americana de Enfermagem ◽

10.1590/1518-8345.5135.3492 ◽

2021 ◽

Vol 29 ◽

Author(s):

Elucir Gir ◽

Mayra Gonçalves Menegueti ◽

Laelson Rochelle Milanês Sousa ◽

Natália Maria Vieira Pereira-Caldeira ◽

Milton Jorge de Carvalho ◽

...

Keyword(s):

Hydrogen Peroxide ◽

Sodium Chloride ◽

Literature Review ◽

Necessary Conditions ◽

Scientific Evidence ◽

Chemical Methods ◽

Ultraviolet Germicidal Irradiation ◽

Dry Heat ◽

Equivalent Method ◽

Sciverse Scopus

Objective: to analyze the scientific evidence available on the different reprocessing methods and the necessary conditions for reuse of the N95 face respirator mask or equivalent. Method: an integrative literature review. The PICO strategy was used to elaborate the question. The search was conducted in four databases: PubMed, SciVerse Scopus, WebofScience and EMBASE, considering any period of time. Results: a total of 32 studies were included from the 561 studies identified, and they were presented in two categories: “Conditions for reuse” and “Reprocessing the masks”. Of the evaluated research studies, seven(21.8%) addressed the reuse of the N95 face respirator mask or equivalent and 25(78.1%) evaluated different reprocessing methods, namely: ultraviolet germicidal irradiation(14); hydrogen peroxide(8); vapor methods(14); using dry heat(5) and chemical methods(sodium hypochlorite[6], ethanol[4] and sodium chloride with sodium bicarbonate and dimethyldioxirane[1]). We emphasize that different methods were used in one same article. Conclusion: no evidence was found to support safe reprocessing of face respirator masks. In addition, reuse is contraindicated due to the risk of self-contamination and inadequate sealing.

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