Validation of gas and vapor sampling methods under field insult conditions

A technique has been developed to validate gas and vapor sampling methods under field insult conditions. Laboratory validation, a necessary aspect of good laboratory practices, only tests the feasibility of a sampling method. "Field validation" determines the effectiveness of a given sampling method in the actual workplace environment where potentially interfering components may exist. A simple and inexpensive means is shown for introducing a known addition spike onto the sampling device during sampling. The validation sample is subject to the same field conditions as area or personnel samples. Upon analysis, recovery of the known addition spike within specified limits, verifies validity of the day's samples. Insufficient known addition spike recovery alerts the hygienist that something has caused sample failure, resulting in an invalid measurement of worker exposure.