Table III.

Microwave and heat intervention parameters, inoculation conditions, and N95 filtering facepiece respirators for which germicidal effect was evaluated

	First author, year	Powera or temperature	Time	Cycles	Moisture	Pressure	Inoculation parameters			N95 models		Summary of germicidal results
							Pathogen	Inoculation medium	Transmission mode
Microwave	Fisher, 2009	750 W/ft3	15 s 30 s 45 s 60 s 75 s	1	MGS	Room	MS2	1% ATCC 271	Aerosol	Cardinal Healthb		Log10 reduction <2 after 15- and 30-s treatments Log10 reduction >4 after 45-, 60-, 75-s treatments
								100% ATCC 271
	Fisher, 2011	750 W/ft3	90 s	1	MGS, steam bag Xc	Room	MS2	100% ATCC 271	Droplet	KC PFR95 3M 1870 Moldex 2200		Log10 reduction >3 for all models/conditions
					MGS, steam bag Yc
	Heimbuch, 2011	1250 Wd	120 s	1	MGS	Room	H1N1	Mucin	Aerosol	3M 8000e 3M 8210e Moldex 1500e	KC PFRe 3M 1860e 3M 1870e	Log10 reduction >4 for all models/conditions
									Droplet
	Lore, 2012	1250 Wd	120 s	1	MGS	Room	H5N1	NR	Aerosol	3M 1860 3M 1870		Log10 reduction >4 for both models
Heat	Fischer, 2020	70°C	10 min 20 min 30 min 60 min	1	Dry	Room	SARS-CoV-2	NR	Droplet	AOSafety N9504C		Log10 reduction <3 after 10-, 20-, 30-min treatmentsf Log10 reduction >3 after 60-min treatmentf
	Heimbuch, 2011	65°C	30 min	1	MHI (85% RH)	Room	H1N1	Mucin	Aerosol	3M 8000e 3M 8210e Moldex 1500e	KC PFRe 3M 1860e 3M 1870e	Log10 reduction >3 for all models/conditions
									Droplet
	Kumar, 2020	121°C	15 min	1	Steam (autoclave)	High (unspecified)	SARS-CoV-2	NR	Droplet	3M 1860 3M Aura 1870 3M Vflex 1804S AOSafety 1054S		Log10 reduction >5 for all modelsg
	Lin, 2018	149–164°C	3 min	1	Dry	Room	Bacillus subtilis	Water	Aerosol	3M 8210		Log10 reduction <3 after dry heath 0 cfu after AC (0% relative survival)i
		121°C	15 min	1	Steam (autoclave)	1.05 kg/cm2
	Lore, 2012	65°C	20 min	1	MHI (RH unspecified)	Room	H5N1	NR	Aerosol	3M 1860 3M 1870		Log10 reduction >4 for both models

AC, autoclave; cfu, colony-forming units; KC, Kimberly–Clark; MGS, microwave-generated steam; MHI, moist heat incubation; NR, not reported; RH, relative humidity.

^aIf both manufacturer-rated and experimentally-determined microwave power were provided, the experimental value is reported here.

^bMask models were anonymized in study. Model name was obtained by e-mail from R. Shaffer in April 2020.

^cSteam bag X = Medela Quick Clean™ MICRO-STEAM™ BAGS; steam bag Y = Munchkin® Steam Guard™ Bags.

^dPower units per volume not specified.

^eMask models were anonymized in article. Model names were obtained by e-mail from B. Heimbuch in April 2020.

^fLog₁₀ reduction calculated as Log₁₀(TCID50/mL)_control – Log₁₀(TCID50/mL)_treatment.

^gStudy reported the mean viral recovery post-decontamination as 0 for each model, with no specified limit of detection. Therefore, the log₁₀ reduction factor is assumed to be equivalent to the Log₁₀(TCID50)_control.

^hLog₁₀ reduction calculated from relative survival rate.

ⁱControl bacterial load not reported, therefore log reduction cannot be calculated.