Airline manufacturers have always known that contaminants from oil from the aircraft engines leaks into the air conditioning of bleed air aircraft. It’s a design fault. 

Airlines know this too. They are sent documentation and guidelines from the manufacturers on how to properly deal with this and clean the air conditioning system thoroughly following a Fume Event. It seems that this documentation and guidance is being disregarded by the airlines because it is a very costly and timely exercise. If an aircraft is in maintenance it is not making the airline money. 

So, rather than deal with the problem in the correct manner, most aircraft are signed off by their engineers with ‘NFF’ - No Fault Found and are put straight back into service. (Because the smell has gone and another fume Event can’t be reproduced on the ground). 

Once back in service it is just a matter of time before another fume event occurs causing more damage to the health of unsuspecting passengers and airline crew. 

Many people ask ‘Why is it mostly the crew who are affected?’ It is because the crew are being exposed to contaminated air most of the time - low level contamination occurs on all aircraft, this can build up in the body to such an extent that the individual starts having health issues. In the case of a Fume Event, it can mean the end of their career or even the end of their life if the toxic load in their body is already at a dangerously high level. We are all different and it depends on the body’s ability to process and eliminate these toxic chemicals. 

Please watch the video.