Table 2.

Geometric mean overall fit factors (GM FF_o) by respirator family, mask size, and bivariate panel size.

Respirator Family	Model Size	Bivariate Panel Size*	Number of Donnings	GM FFo	GSD FFo	Min FFo	Max FFo	Duncan’s Grouping†
Three-size family	Large	Large	11	11,677	3.0	1,905	46,527	A
		Medium	26	8,454	5.9	14	40,496	A
		Small	12	7,246	9.7	17	53,298	A
	Medium	Large	9	4,118	14.3	15	53,538	A
		Medium	25	6,228	8.2	43	43,255	A
		Small	12	2,519	14.6	14	46,293	A
	Small	Large	9	1,407	14.7	20	20,364	A
		Medium	26	4,508	5.5	72	49,284	A
		Small	12	6,374	10.9	10	39,227	A
Two-Size Family	Large	Large	11	216	22.0	2	20,576	A
		Medium	26	1,516	11.7	13	34,375	A
		Small	12	213	31.8	2	42,380	A
	Regular	Large	9	36	10.6	2	1,231	A
		Medium	26	259	13.0	4	15,641	A
		Small	11	214	11.4	3	11,609	A
One-size family	One-Size Only	Large	11	1,251	6.5	106	12,143	A
		Medium	26	2,163	7.0	10	20,950	A
		Small	12	935	19.1	13	24,246	A

^*1–3 constitute “small”, Cells 4–7 constitute “medium,” Cells 8–10 constitute “large.”

^†Groups that have statistically different GM FF_o will have different letters.