Table I.
Characteristics of included studies
| Interventions | Study | Intervention | Procedure |
Mask/component tested | Testing agent | Control | |||
|---|---|---|---|---|---|---|---|---|---|
| Duration | Cycles | Temperature | Other | ||||||
| Decontamination | Lin et al. [21] | Dry heat (rice cooker) | 3 min | 1 | 149–164°C | – | Mask pieces: 1. Gauze double-layer electret mask 2. Oimo spunlace non-woven masks (models not specified) |
Potassium sodium tartrate tetrahydrate solution (polydispersed droplets) | Untreated mask piece |
| Moist heat (autoclave) | 15 min | 1 | 121°C | Pressure: 1.06 kg/cm2 | |||||
| Ethanol, 70% | 10 min submersion | 1 | Room | Air-dried overnight | |||||
| Isopropanol, 100% | 10 min submersion | 1 | Room | Air-dried overnight | |||||
| Sodium hypochlorite solution, 0.5% | 10 min submersion | 1 | Room | Air-dried overnight | |||||
| Pre-contamination | Quan et al. [25] | Salt (NaCl) coating: 3, 7, 11, 14, and 19 mg NaCl/cm2 |
Solution 1: overnighta Solution 2: 1 daya |
1 | Room | Oven-dried 37°C × 1 day | Salt-coated pieces of polypropylene mask filter (mask model not specified) | Aerosolized virus: H1N1 CA/09 H1N1 PR/34 H5N1 VN/04 |
Uncoated mask filter |
| Tseng et al. [27] | Quaternary ammonium agent (Goldshield 5; GS5), 1% in sterile water | Applied with common spray bottle (4 sprays = 1 mL) |
Room | Air-dried × 24 h | GS5-coated pieces of 3 mask layers and GS5-coated full mask (AERO PRO, Taiwan; model not specified) | Aerosolized bacteria: A. baumannii ATCC17978 E. faecalis ATCC29212 S. aureus ATCC29213 |
Sterile water-coated mask | ||
| Demir et al. [22] | N-halamine (1-chloro-2,2,5,5-tetramethyl-4-imidazolidinone), 1 wt% in ethanol | 10 min submersion. Padded through laboratory wringer |
1 | Room | Air-dried × 24 h | N-halamine-coated pieces of polypropylene mask filter (Hollingsworth & Vose Co., USA; model not specified) | Aerosolized bacteria: S. aureus ATCC6538 E. coli 0157:H7 ATCC43895 |
Uncoated mask filter | |
| Li et al. [24] | Silver nitrate and titanium dioxide nanoparticle emulsion, 0.4 mg/cm2 | Coated to desired concentration with textile-finishing machine (China patent 03142467) |
Full masks with nanoparticle-coated outermost mask layer (Winner Medical Group, China; model not specified) |
Aerosolized pathogen simulant: KCl–fluorescein | Uncoated mask layer | ||||
| Li et al. [23] | Silver nitrate and titanium dioxide nanoparticle emulsion, 0.4 mg/cm2 | Coated to desired concentration with textile-finishing machine (China patent 03142467) | Nanoparticle-coated pieces of outermost mask layer (Winner Medical Group, China; model not specified) | Bacterial suspensions: E. coli ATCC25922 S. aureus ATCC25923 |
Uncoated fabric | ||||
| Shen et al. [26] | Fluorochemical repellent (Zonyl® PPR Protector), 6% and 12% | Unspecified submersion time. Padded through laboratory wringer |
2 | Room | Dried at 176°F × 2 min. Cured at 250°F 2 min |
Three full masks made of nonwoven mask components with repellant applied to cover layer (models not specified) | Aerosolized pathogen simulant: Latex micro-spheres + synthetic blood | Uncoated mask | |
ATCC, American Type Culture Collection; GS5, Goldshield 5 quaternary ammonium agent; H1N1 CA/09, H1N1 influenza virus (A/California/04/2009); H1N1 PR/34, H1N1 influenza virus (A/Puerto Rico/08/2934); H5N1 VN/04, H5N1 influenza virus (A/Vietnam/1203/2004); KCl, potassium chloride; NaCl, sodium chloride.
a
Incubated in 600 μL of salt-coating solution overnight at room temperature, then immersed and oven-dried for one day in a second salt-coating solution (0, 100, 300, 600, 900, or 1200 μL) to achieve different salt-coating (sodium chloride, in mg) on filter per unit area.