Table 2.

Median total PAH concentration (μg/filter) on PTFE filters under jackets (chest). Ratios calculated using median ambient chamber air PAH concentrations are also provided in parentheses to estimate protection factors.

	Laundered					Decon
	Hook		Zipper		Hook vs Zipper	Zipper
Exposure Trial	N	Median Total PAH (RatioA)	N	Median Total PAH (RatioA)	p-valueB	N	Median Total PAH (Ratio)
New	3	6.28 (45,500)	2	7.07 (44,400)	0.037	1	7.23 (39,500)
10	3	15.6 (14,400)	3	2.01 (112,400)		3	4.46 (50,600)
20	2	11.5 (25,900)	3	3.63 (43,400)		3	7.34 (21,400)
40	1	7.68 (9,200)	3	7.35 (9,600)		3	5.53 (12,800)
Trend P-valueC		0.1		0.01			0.105

^ATo estimate the impact of repeated exposure and laundering on PPE protection factors, we calculated the ratio of median ambient chamber air PAH concentrations (table 1) to median PAH levels on PTFE filters under jackets (chest region).

^BP-value from multiple linear regression of the log-transformed ratios of PAHs deposited under jackets in the chest region to median ambient chamber air PAH concentrations by type of jacket closure, controlling for cleaning cycles/exposure trial

^CP-value from multiple linear regression of log-transformed ratios vs. cleaning cycles/exposure trial, controlling for type of jacket closure