A new passive sampler for regulated workplace ketones

A new solid sorbent passive air sampler for ketones has a silicone membrane atop a diffusion cylindrical path length of 1.1 cm and diameter 1.3 cm abo ve a pellet of Tenax TA coated with 10% (w/w) O-(2,3,4,5,6-pentafluorobenzy l)hydroxylamine hydrochloride. Vapors of known concentrations approximating their workplace permissible exposure limits of Occupational Safety and Hea lth Administration-regulated ketones at a relative humidity (RH) of 3 +/- 1 % were generated by a syringe pump connected to a dynamic air dilution syst em connected to an exposure chamber that allowed measurement of face veloci ties, temperatures, exposing vapor concentrations, and RHs. The O-oxime der ivative was desorbed with hexane, and an aliquot injected for gas chromatog raphic analysis on a nonpolar capillary column by mass spectrometric or ele ctron capture detection. The experimental passive sampler sampling rates in milliliters per minute at 25 degreesC were 4.07 +/- 0.49, cyclohexanone; 6 .30 +/- 0.59, diethyl ketone; 6.31 +/- 0.31, ethyl n-butyl ketone; 3.78 +/- 0.25, methyl n-amyl ketone; 3.43 +/- 0.19, methyl n-butyl ketone; 6.48 +/- 0.64, methyl ethyl ketone; 4.37 +/- 0.43, methyl isopropyl ketone; and 4.5 7 +/- 0.17, methyl n-propyl ketone. These preliminary data show that steric ally unhindered ketones can be sampled by the passive sampler as well as al dehydes.