Table 1.
Study characteristics
| Study, country |
No. of participants (% male) |
Age range (years), (mean*) | Population | Population ethnicity† (%) |
RPE type Number of brands/models/sizes (RPE tested per user)**** |
No. of facial dimensions | RPE fit measure (guidelines/standards) and outcome |
| Liau et al, USA48 | 190 (100%) |
N/A | Laboratory employees | Caucasian | Reusable half mask 4 brands, 10 sizes total |
7 | QNFT Protection factor |
| Gross and Horstman, USA49 |
121 (50%) |
(37.5) | Community members | N/A | Reusable half masks 3 brands (2), 3 sizes each |
10‡ | QNFT§ (ANSI) Fit factor, pass rates |
| Oestenstad et al, USA50 | 73 (53%) |
21–50 (30.6) | University student, staff and faculty | White (68%) Black (12%) Asian (12%) Other¶ (7%)** |
Reusable half mask 1 brand, 3 sizes |
12 | QNFT (ANSI) Leak shape, size and distribution†† Fit factor |
| Oestenstad and Perkins, USA27 |
68 (56%) |
21–50 (30.4) | University students and staff | White (69%) Black (13%) Asian (10%) Hispanic (4%) Asian Indian (3%)** |
Reusable half mask 1 brand, 3 sizes |
12‡ | QNFT†††† (ANSI) Fit factor |
| Brazile et al, USA51 |
186 (49%) |
N/A | Community members, university students | White (35%) African (31%) Mexican (33%) |
Reusable half mask 1 brand, 3 sizes |
14‡ | QNFT§ (ANSI) Fit factor, pass rates |
| Han, South Korea52 | 778 (52%) |
20–55 | Industrial workers, university students | Korean | Reusable quarter mask 3 brands (3) |
2 | QNFT‡‡(ANSI) Fit factor, pass rates |
| Han and Choi, South Korea29 |
150 (75%) |
20–55 | Community members, university students | Korean | Reusable half mask 3 brands (3), 1 size (M) |
10‡ | QNFT‡‡(ANSI/OSHA) Fit factor, pass rates |
| Kim et al, South Korea53 |
110 (64%) |
N/A | University students | Korean | Reusable quarter mask 3 brands (3), 1 size (M) |
12‡ | QNFT§‡‡ (ANSI/OSHA) Fit factor, pass rates |
| Zhuang et al, USA54 |
32 (45%) |
N/A | N/A | N/A | Disposable N95 half mask 18 models (18), 1–3 sizes |
12‡ | QNFT SWPF |
| Oestenstad et al, USA55 | 41 (51%) |
20–55 (30) | Institute student and staff | Caucasian | Reusable half mask 3 brands (3), >1 size |
12‡ | QNFT Fit factor |
| McMahon et al, Canada56 |
1295 (24%) |
19–71 | Healthcare workers | N/A | Disposable N95 half masks 3 brands§§, 6 models |
N/A | QLFT Pass rates |
| Zhuang et al, USA57 |
30 (43%) |
N/A | Community members | While (90%) Black (33%) Asian (66%) |
Disposable and reusable half masks 4 models (4), 3 sizes |
3 | QNFT‡‡ Fit factor, pass rates |
| Winter et al, Australia58 |
50 (N/A) |
N/A | Healthcare workers | N/A | Disposable N95 half masks 2 brands, 3 models (3) |
1 | QLFT |
| Wilkinson et al, Australia59 |
5024¶¶ (21%) |
Mode age group: 41–50 | Healthcare workers | Aboriginals (0.9%) White (88.9%) East-Asian (5.7%) South/Central- Asian (3.5%) Other*** (1.0%) |
Disposable P2/N95 half masks 3 brands§§, 1–2 sizes |
N/A (overall face shape/size data collected) |
QNFT‡‡ Pass rates |
| Oestenstad and Bartolucci, USA60 | 41 (51%) |
20–55 (3) | University students and staff | Caucasian | Reusable half masks 3 brands (3) |
12‡ | Leak size, shape and distribution †† |
| Spies et al, South Africa61 |
29 (48%) |
N/A | Research institute employees | African (45%) European (41%) Coloured††† (7%) Asian (7%) |
Disposable P2 half mask 1 model, 1 size (M) |
4‡‡‡ ‡ | QNFT‡‡ (OSHA) Fit factor, pass rates |
| Ciotti et al, France30 | 50 (N/A) |
N/A | Healthcare workers | N/A | Disposable PPF2 half masks 9 models (2-3) |
N/A | QNFT‡‡ Fit factor, pass rates |
| Earle-Richardson et al, USA62 | 56 (88%) |
15–81 (33.2) | Farmworkers | Latino | Disposable N95 and reusable half masks 4 brands, 7 models§§ |
N/A | QLFT (OSHA) Pass rates |
| Yu et al, China63 | 50 (52%) |
Mean age (SD) 21.5 (2.2) |
N/A | Chinese | Disposable N95 half masks 4 brands, 10 models (10), 2 sizes |
21‡ | QNFT‡‡ (OSHA) Fit factor, pass rates |
| Bergman et al, USA64 | 229 (N/A) |
N/A | General population | N/A | Disposable N95 half masks 7 models§§, 1–2 sizes |
13 | QNFT‡‡ (OSHA) Fit factor, inward leak |
| Kim et al, South Korea65 |
49 (67%) |
Mean age (SD) 23.0 (3.8) |
Healthcare workers | Korean | Disposable N95 half masks 1 brand, 2 models, 3 sizes |
7‡ | QNFT‡‡ (OSHA) SWPF, fit factor, pass rates |
| Lin and Chen, Taiwan66 | 206 (49%) |
21–30 | Community members, university students | Taiwan | Disposable N95 half masks 3 models (3), 1 size |
19‡ | QLFT (OSHA) |
| Manganyi et al, South Africa28 |
562 (33%) |
Mode age group: 19–30 years | Laboratory employees | African (65%) Asian (11%) Coloured§§§ (9%) White (14%) |
Disposable N95/FFP2 half masks >2 brands (1) ¶¶¶, 2 sizes (S, M) |
4 | QNFT‡‡ (OSHA) Fit factor, pass rates |
| Honarbakhsh et al, Iran67 | 95 (33.5%) |
N/A | Healthcare workers | Taiwanese | Disposable N95 half masks 3 models, 1 size |
2‡ | QLFT (OSHA) Pass rates |
| Huh et al, South Korea68 |
211 (51%) |
Median 26 IQR 23–31 |
Military hospital volunteers | Korean | Disposable N95 half masks 3 brands, 4 models (4), 1–3 sizes |
2 | QNFT‡‡ (OSHA) Fit factor, pass rates |
| Foereland et al, Norway69 | 127 (88%) |
18–65 (37) | Smelting industry workers | Norwegian | Disposable P3 half masks 4 brands, 14 models (≥5), 1 or 3 sizes |
N/A | QNFT‡‡ (OSHA) Fit factor, pass rates |
| Winski et al, UK70 |
262 (90.5%) |
N/A | General population | N/A | Disposable PPF3 half mask 1 model |
3 | QNFT‡‡ (BSIF) Fit factor, pass rates |
| Fakherpour et al, Iran71 | 62 (40%) |
Mean age (SD) 23.45 (4.66) |
University students | Iranian | Disposable N95/PPF2/FFP3 half masks 4 brands (4) |
2‡ | QLFT Pass rates |
| Zhang et al, China72 |
85 (36%) |
Mean age (SD) 27 (4.4) |
University students | Chinese | Disposable N95/FFP3 half masks 4 models (4), 1 size |
8 | QNFT‡‡ Fit factor, pass rates |
| De‐Yñigo‐Mojado et al, Spain73 |
74 (50%) |
Mean age (SD) 34.31 (7.13) |
Healthcare workers | N/A | Disposable FFP3 half masks 2 brands, 3 models |
4‡ | QNFT‡‡ Fit factor, pass rates |
| Fakherpour et al, Iran74 | 37 (32%) |
Mean age (SD) 24.6 (4.2) |
University volunteers | Iranian | Disposable N95/FFP2 half masks 15 brands, 20 models (20) |
2 | QNFT‡‡ Fit factor, pass rates |
| Williams et al, Australia75 | 96 (57%) |
Mean age (SD) 42.3 (9.5) |
Healthcare workers | South East Asian (26%) Other (74%) |
Disposable N95 half mask 2–3 models§§, 2 sizes |
N/A | QNFT‡‡ (OSHA) Fit factor, pass rates |
*Unless otherwise stated.
†Ethnicity as reported by authors of respective studies. Efforts were made to determine ethnicity if not clearly reported.
‡Studies with anthropometric data reported for inclusion in meta-analysis.
§QNFT FF score of 10 used as equivalent to effective protection using particulate detector or condensation nuclei count (portacount) method.
¶Hispanics and Asian Indians.
**Data on ethnicity collected but no comparison made due to small numbers.
††RPE performance measured used fluorescent tracer.
‡‡QNFT FF score of 100 used as equivalent to effective protection using condensation nuclei count (portacount) method.
§§An initial respirator was selected. Once a successful fit test was obtained other models were not tested. In the event of failed testing, subsequent models were tested until fit-testing was passed.
¶¶Survey study design, with ‘no. of participants’ representing number of healthcare workers who responded to the questionnaire and were tested with the respirators. Percentage of males calculated number of questionnaires where participants supplied information on gender.
***Not reported.
†††Mixed European, African or Asian ancestry as per consensus referenced in the study.
‡‡‡Two measurements taken for all participants, two additional measurements taken on small proportion of participants.
§§§Mixed-race, combination of ethnic backgrounds including African, White, Khoisan, Indian and Malay.
¶¶¶Participants were tested using the type and size of mask used in the workplace at the time of study.
****Number of brands/models/sizes included in the study. (N) describes the number of masks tested per participant, where reported. Intra-study variability in number of masks tested per participant observed.
††††QNFT FF score of 1000 used as equivalent to effective protection using photometric method.
ANSI, American National Standards Institute; BSIF, British Safety Industry Federation; FF, fit factor; N/A, not available/reported; OSHA, Occupational Safety and Health Administration; PF, protection factor; PR, pass rates; QLFT, qualitative fit test; QNFT, quantitative fit test; RPE, respiratory protective equipment; SWPF, simulated work place protection factor.