Validation of passive air sampling monitors onboard United States Navy submarines

An operating submarine creates a unique air quality mixture of compounds that result from a combination of human metabolism, construction materials, materials brought onboard and compounds created through the interaction of ship systems. A comprehensive study of submarine atmospheres is ongoing during deployments of U.S. Navy nuclear submarines. As part of the overall effort, a paired air sampling comparison field validation was conducted to compare the air sampling effectiveness of passive diffusive monitors compared to more traditional active air sampling methods when sampling for acrolein, formaldehyde and ozone in the enclosed submarine atmosphere. Acrolein monitors containing 2-hydroxymethylpiperidine (HMP) impregnated glass fibers and 2-HMP silica gel as sorbent media, formaldehyde monitors containing adsorbing media of 2,4-dinitrophenylhydrazine (DNPH) and ozone monitors with a sorbent bed of nitrite impregnated glass fibers were evaluated. Active sampling was conducted in accordance with NIOSH Method 2501, NIOSH Method 2016 and OSHA Method ID 214 for acrolein, formaldehyde and ozone respectively. Extended sampling periods ranging from 14 to 28 days for active sampling methods and 28 days for passive monitors were necessary due to the trace airborne concentration levels of these airborne contaminants. Validation tests of the resulting active and passive air sampling data indicated that the acrolein, formaldehyde and ozone passive monitors were not validated to sample the very low concentrations of these contaminants aboard U.S. Navy nuclear submarines. Depending on the airborne contaminant, the passive monitors had an average estimated accuracy ranging from +/-82.1% to +/-237.4% and log(10) transformed correlation coefficients ranging from 0.0043 to 0.5289 (r2 = 0.0043--0.5289). Although the passive monitors as tested were not validated for the enclosed submarine atmosphere, minor modifications to the passive monitors and improved laboratory analytical sensitivity will likely improve their effectiveness and additional validation testing conducted using the guidelines provided by this study is warranted.