EASA publishes two studies on cabin air quality
The European Aviation Safety Agency (EASA) has published two studies it commissioned with the aim to gain solid scientific knowledge about cabin air quality on board large aeroplanes operated for commercial air transport. The agency found that the cabin/cockpit air quality is similar or better than what is observed in normal indoor environments. It also found that neuroactive products are present in very low concentration.
The first study on the cabin air quality (CAQ) measurement campaign was conducted by a consortium of the Fraunhofer Institute for Toxicology and Experimental Medicine and the Hannover Medical School.
In-flight measurements have been conducted on a number of commercial flights after defining adequate and reliable air contaminants measurement methods for cockpit and passenger cabin areas.
The results show that the cabin/cockpit air quality is similar or better than what is observed in normal indoor environments (offices, schools, kinder gardens or dwellings). No occupational exposure limits and guidelines were exceeded.
In total, 69 measurement flights were performed between July 2015 and June 2016 on 8 types of aeroplane/engine configurations. This included 61 flights on aeroplanes equipped with engine bleed air systems, and 8 flights on Boeing 787 which is equipped with electrical compressors (‘bleed free’ system). For all flights, measurement equipment was installed in the cockpit and in the cabin. Special attention was paid to organophosphates, in particular Tri Cresyl Phosphates (TCP) with the use of high sensitivity analysis techniques.
The second study, on the characterisation of the toxicity of aviation turbine engine oils after pyrolysis, conducted by a consortium of the Netherlands Organisation for Applied Scientific Research and the Dutch National Institute for Public Health and the Environment.
This study characterised the chemical composition of some transport aeroplane turbine engine oils (including pyrolysis breakdown products), and the toxic effects of the chemical compounds that can be released in the cabin or cockpit air.
It concluded that neuroactive products are present, but that their concentration in the presence of an intact lung barrier is too low to be a major concern for neuronal function. TCP was present in the analysed oils, however no ortho-isomers could be detected. Finally the analysis of the human sensitivity variability factor showed that the complete metabolic pathway and the contribution of inter individual variability in the metabolic enzymes is still largely unknown for the majority of industrial chemicals, including cabin air contaminants. Two brands of oil were used in this study, and both new and used oil samples were analysed.
As a follow-up activity, further research has started in a European Commission (EC) study, with technical support from EASA. It will take into account the findings and recommendations from the two EASA studies to develop a comprehensive understanding of the cockpit and cabin air quality.