Dr Andrew Hobson from Quantitech, the specialist analytical instrument company, is urging the users of breathing gas to check that their supplies are tested for all potential contaminants, and not just the most common compounds. He says, “It is important to use an analytical technique such as FTIR because this methodology provides a spectrum result in addition to concentration measurements for a wide range of parameters,” adding: “This is important because unusual peaks occur in the spectrum when unknown contaminants are present.”
The standard BS EN 12021 requires that all contaminants should be kept to as low a level as possible and shall be not greater than 10% of the UK 8hour time weighted average exposure limits which are specified in the HSE publication EH40. However, contamination can occur when gases or vapours are drawn into a compressor accidentally as a result of a leak or a spillage, or from a nearby chemical reaction or combustion process. As a result, any analysis of the compressed gas that only measures specific compounds is unlikely to detect any unforeseen contamination and this is the reason for FTIR being the preferred analytical technology for breathing gas analysis.
Warning for users of breathing gas