BackgroundAs 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.