Carbon monoxide as an indicator of indoor air quality

Carbon monoxide has long been known as an indoor air pollutant, but has rarely been in the focus of scientific interest. This circumstance is certainly disadvantageous for the health-related assessment of indoor air quality, because exposure to carbon monoxide is often associated with serious or fatal poisoning. From an analytical perspective, the problem is that increased carbon monoxide concentrations often occur unexpectedly and within a short period of time, usually in connection with incomplete combustion processes. Therefore, the exposure of the general population to carbon monoxide cannot be determined using environmental surveys. In recent years, however, carbon monoxide has again received significantly greater attention. A number of studies have been carried out on carbon monoxide exposure under certain conditions, for example when using candles, gas stoves or in waterpipe cafés. In addition, the World Health Organization has derived guideline values for different exposure times. Due to its molecular properties, carbon monoxide is very suitable for selective and sensitive measurement with high time resolution using infrared techniques. In addition, sensor technology has made significant progress, so that robust devices are now available for online monitoring. Carbon monoxide can definitely be considered a priority pollutant for indoor air. Actually, increased concentrations are always associated with health risk. It is therefore recommended to use carbon monoxide as an indicator of indoor air quality. This can be realized in a variety of ways and preferably in combination with other parameters.