It is unusual to post six articles here, but it is also curious that all of them discuss aviation safety, as argued in various courts, without any complaint filed with the FAA or other CAA. Two reports indicate that two of the plaintiffs received damages, one from the carrier for which the flight attendant worked and the other from Boeing. The most recent lawsuit was filed in the US against Boeing, but others have brought complaints against Airbus. There may be as many as 20 of these toxic air lawsuits. While all of this litigation may signal that cabin air poses risks, are the risks sufficient to revise aircraft certification standards or are these isolated instances in which the risks are insufficient?
What is the validity of these assertions? Has there been any regulatory response?
First, a description of the scientific basis for the damages claim is relevant. The Explainer writer lists the elements of the problem and here is a list of the essential elements of this theory:
- “Symptoms may be the result of exposure to the organophosphate known as tricresyl phosphate (TCP); a flame retardant additive in jet engine oil and hydraulic fluids. As well as acting as an irritant, these substances are a type of neurotoxic compound, and can interfere with nervous system functions, resulting in cognitive, emotional and behavioural problems.”
- “Air is supplied throughout the aircraft to allow crew and passengers to breathe. The human body is used to breathing in air of around 15°C, at a pressure of 14.7 pounds per square inch or psi (at sea level). However, at an altitude of 35,000 feet the air pressure is only 3.46 psi with temperatures lower than -50°C, so fresh air is pumped into the plane from outside the aircraft but only after it is warmed and pressurized to a safely breathable level.”
- “As part of the propulsion process, aeroplane engines heat and compress air before fuel is added and combusted. On most aircraft this air is then “bled off” and pumped into the aircraft, unfiltered. Ordinarily this process is relatively safe. But occasionally faulty seals can result in contamination by allowing heated and broken down engine oil fumes to escape into the airflow.”
- “There is also significant under-reporting of exposure: for example, the Committee on Toxicity of Chemicals in Food, Consumer Products and the Environment estimated that fume events occur on about 0.05% of flights.”
- “To better establish the incidence of fume events, the UK Department for Transport commissioned Cranfield University to carry out an air monitoring study of affected aircraft types. They monitored 100 flights, measuring the levels of several chemical compounds that were present in the cabin during different stages of flight. A number of chemicals were detected over the course of this study, including TCP and carbon monoxide.”
- “All levels were reported to be within safe limits – regardless of an absence of aircraft safety standards regarding TCP. While reassuring for routine flight safety, no fume events were observed in this small sample size due to the relative rarity of cabin air contamination. The study reinforced the lack of clarity around possible exposure that aircrew and passengers may face during a fume event.”
The above explanation indicates that TCP exposure may have significant consequences, but also suggests that the likelihood of exposures is a risk of five hundredth of a percent.
In 2013, at the direction of the FAA Modernization and Reform Act of 2012, H.R. 658 (the Act), Section 917, the FAA studied this phenomenon and issued a Report to Congress entitled “SECTION 917– RESEARCH AND DEVELOPMENT OF EQUIPMENT TO CLEAN AND MONITOR THE ENGINE AND AUXILIARY POWER UNIT (APU) BLEED AIR SUPPLIED ON PRESSURIZED AIRCRAFT.” The process which the FAA used was summarized as follows:
- “Summarized FAA research in the area of sensors and prognostics to mitigate bleed air contamination events.
- Reviewed and summarized available industry safety data related to engine and auxiliary power unit bleed air contamination events involving oil based contaminants.
- Conducted a request for information through the Federal Register seeking information on technologies for removing oil-based contaminants from the bleed air and detecting and recording oil-based contaminants in the portion of the total air supplied to passengers and flightdeck crews from bleed air.”
The research and development status was promising with expectations of better control of the bleed air, purification of the recirculation air, improved sensors and reduction of the parasitic potential of the powerplant sometime in the immediate future. The recommendation was that these on-going research efforts would be incorporated in policy and standards as the findings were declared as reliable.
The conclusion of the report was summarized as follows:
“As shown by the search summary, the occurrence of oil or hydraulic based contamination of bleed air is extremely low. In formulating the annual aviation safety research portfolio, the FAA evaluates the relative risk of aviation safety hazards and the potential for safety improvement. The FAA will continue to consider cabin safety risk and sponsor research in this area appropriate to the risk level.”
While the incidence rate is small, those who fly as their jobs or frequent fliers are subject to multiple events in which to be exposed. Perhaps, Administrator Huerta should ask for an update to this 2 year old report to see if any of the developing technologies can provide improved air now. Given OSHA’s proclivity to duplicate the FAA’s safety mandate, such proactive initiative might be worthwhile.
ARTICLE: Flight Attendant Wins Suit Over Bad Air On Plane (dated 9/10/2010)
ARTICLE: Flight attendant ‘poisoned’ by aircraft fumes wins payout, sparking fears over passengers breathing ‘toxic air’ (dated 10/17/2011)
ARTICLE: We’ll be looking for TOMBSTONES: A Boeing engineer’s DEADLY warning about toxic cabin air (dated 8/13/2014)
ARTICLE: Explainer: is aircraft cabin air toxic? (dated 6/20/2015)
ARTICLE: Is Airplane Cabin Air Toxic? (dated 6/22/2015)
ARTICLE: Boeing sued over ‘toxic’ plane cabin air (dated 6/23/2015)Share this article: