Validation of a carbon monoxide sampling method using polypropylene syringes: a reliable alternative method, easy to...

Carbon monoxide (CO) is a lethal gas, present during incomplete combustion of carbonaceous materials. CO may be present in certain occupational atmospheres or during accidental events such as fires. Colorless and odorless, its presence can only be detected analytically. Nevertheless, the measurement methods available today may either be lacking (not available, for example, for military people deployed in the field) or not completely adapted (interference for electrochemical detectors, cost for infrared detectors). Another solution is to take samples on the field and then analyze them in a laboratory. Tedlar® bags or canisters can be used for this purpose but are relatively cumbersome. An alternative, not well described in the literature and not metrologically validated, consists in using plastic syringes. In order to generalize the use of this system and to characterize it in terms of performance and stability over time, we conducted a validation study. This method was validated using a 50-cc polypropylene syringe, over a concentration range of 2 to 40 ppm. The sampling system is efficient (sample yields between 101 and 102%) and repeatable (relative standard deviations under 2%). Storage tests were conducted on syringes containing 2 and 20 ppm carbon monoxide, indicating that the syringes can be stored for up to 2 weeks in the dark at room temperature. Coupled with a laboratory infrared analysis, this technique allows a high sensitivity and specificity. Easy to implement, rugged, inexpensive, and energy self-sufficient, this sampling system is attractive and offers a new solution for field or accidental situations.