The debate over cabin air quality (CAQ) on commercial aircraft is not a novelty. And yet, the issue lingers. The lack of conclusive scientific evidence on the negative impact of aircraft air used via the ‘bleed air system’ is lagging behind the growing number of personal experiences voiced by crew and pilots. As ECA’s recent position paper shows, however, to minimise the flight safety implications of ‘fume events’ in an aircraft, and to prevent the potential short- term or long-term health effects, there are many steps that can and should be undertaken already today.
The cabin air on commercial aircraft is produced through a so-called bleed air system that compresses the air taken from the engines and let it to the cabin without filtering. The problem arises when the system – used by all the operational aircraft except for the new Boeing 787 Dreamliner – gets contaminated with oil fumes leaking from the hot section of the engine.
Since these fume events are considered rare, highlighting their safety risks and quantifying the magnitude of the problem remains a challenge.
Where is Europe today?
The possible air contamination by chemicals is acknowledged by the widest spectrum of the industry. From regulatory authorities and oil manufacturer through scientists and airlines occupation doctors to crew associations; the issue is known and requires answers. Since EASA announced an external research tender on air contamination measurements in 2014, the CAQ matter is now set higher up on the European agenda once again.
The research is vital and it aims at implementing a preliminary in-flight measurement campaign to use adequate instruments to measure cabin/cockpit air contamination and providing concrete indications of the cabin/cockpit air quality level.
In parallel, the systematic reporting of fume events - in line with the principles of Just Culture - was made mandatory in Europe since November 2015. This allows crew members to report any occurrences while also protecting the author of the report against the inappropriate use of safety information, marking another important step in addressing the CAQ related questions.
Where does ECA stand?
ECA has published its in-depth position paper in December 2015, in which, it calls for a continuous development of new technologies that can assist in further reducing the occurrence and effects of fume events.
The position paper also emphasises the importance of distinguishing between the possible safety repercussions stemming from abnormal situations (e.g. fume events in the cockpit or the cabin) and the potential long-term health effects of such events. Whereas the latter one requires a reliable factual backup, the need to address the likely hazard of fume events is immediate.
For this reason, ECA outlined the most essential actions in regards to CAQ to avoid any compromise on flight safety. Among others, it recommends the continuous improvements of filtering and detections systems with the long-term aim of bleed-free aircraft designs, better crew training to reduce safety risks, and more explicit harmonised operation procedures for fume events.
Fume events continue to occur and so should the dialogue around them. The results of the scientific research are expected to be published in autumn 2016, but until then, stakeholders should keep on ensuring that safety remains a top priority in European aviation.