The validation of a permeation cell for testing chemical protective clothing

The performance of a simple rugged permeation cell for testing chemical pro tective clothing was compared with the reference cell suggested by the Amer ican Society for Testing and Materials and using their validation protocol. The new cell overcomes some of the limitations of the reference cell inclu ding ruggedness, low dead space, ease and speed of use, and small sample si ze. The testing of the new cell was performed under standard conditions usi ng acetone against reference neoprene with an automated test system incorpo rating a photoionization detector. The performance of the new cell was foun d to be within the acceptance criteria for normalized breakthrough time and steady state permeation rate. The normalized breakthrough time index was a major impediment to the automated testing of more than one cell at it time , as it required a very low degree of cross contamination between cells, if a shared detector was used. It is suggested that lag times rather than nor malized breakthrough times form part of the basis for comparison of permeat ion cells. The pretreatment of test samples to remove volatile contaminants requires consideration.