Measurement of thermal comfort and indoor air quality aboard 43 flights on commercial airlines.

This paper reports the results of thermal comfort and indoor air quality measurements aboard aircraft from 43 flights on commercial airlines with a duration of more than 1 h. The measurements were performed continuously during the whole flight (from the departure gate to the arrival gate), and the parameters monitored were temperature, relative humidity and carbon dioxide concentration. The results were then compared with the ASHRAE Standards for the thermal comfort (ASHRAE Standard 55-92) and indoor air quality (ASHRAE Standard 62-89). The evaluation of the indoor air quality was based mainly upon comparison of the carbon dioxide concentrations measured with standards and recommendations for the indoor environment. Overall, the levels of relative humidity were far lower than the limit set by the ASHRAE Standard 55-92. The levels of carbon dioxide on most flights were higher than that recommended by the ASHRAE Standard 62-89. The results of this study, mainly the low level of humidity and high concentrations of carbon dioxide, led us to expect that the crew and the passengers would have been dissatisfied with their degree of thermal comfort and the quality of the air in the cabin. This conclusion is based simply on a comparison of our measurements with the values stated in the ASHRAE Standards. However, we must bear in mind that these were developed for an indoor environment at atmospheric pressure. More research is needed to study the validity of these standards for sub-atmospheric conditions.