'Toxic' cabin air found in new plane study - Telegraph
 

"Samples taken secretly from the planes of popular airlines have raised fresh concerns over passengers inhaling contaminated air."

'Toxic' cabin air found in new plane study - Telegraph

Seems this contaminated cabin air issue keeps raising its head, and the industry still needs to sort it out!

Indeed it does need sorting out one way or the other. However I would take issue with:-

That is quite some group of workers but was not aware that I had signed up to it. Has anyone?

yep i have


Neil

More about the samples and results as well as reactions can be found here:

The toxic subject that won't die - Learmount


happy (fume- and oilsmell-less) landings

TvB

Is it really oil???
 

Whilst not wanting to lessen the concern on oil contamination, how much of it is down to perception?

A recent incident was down to spilt milk in the galley. The incidences are moving to other fleets also.

Funny smell, can't quite put your finger on it? Only momentary? Was it atmospheric ie. the area you are passing over?

Every report at my company is considered seriously and testing of systems is carried out. Usually nothing is found. If anything is found further action is taken.

As regards to this "secret" testing, does the report give aircraft types?

OK, just read the Flight Global write up!

KB, I guess, until the potential for oil fume contamination has been eliminated, and as the whole topic gets more and more publicity, we are going to find more and more people reporting things which would otherwise have been missed or dismissed at the time. You do have a valid point but, given the apparent risks associated with this contamination, I would expect the level of reports, including false alarms, to increase.

Hot 'n' High

It would be intresting reading to see all reports, all aircraft types, at what stage of flight ..... and destination (possible conspiracy to stay at a lovely destination?) Sorry being a bit cynical here. I agree that all reports should be made so as to build a history. Without the ammunition, there is no case. I certainly would not want to be on flights where these incidences occur, self preservation and all that.

KB,

Quite agree! Me neither! :ooh:

Once, some years back, as Mil pax, got marooned in Bermuda for three days when the Herkybird went "Tech"! Now, that was tough!!! :ok:

At least this topic is being discussed more widely. However, just to be even more cynical than you (:}) I suspect nothing much will really happen until the Lawyers jump on the bandwaggon! :ugh:

Like to know if anyone in Design is looking into this so, at least, the next generation don't suffer from this? One hell of a Mod programme for existing fleets ...... so probably nothing going to happen there - for a while!

H 'n' H exits "Cynic Mode"!!!!!

Times and concentrations?
 

There's no indication in the Flight Global report of the concentrations of TCP in the air of the aircraft, or how long it took for the amount they found to accumulate. Is it a long-term slow release, or occasional rapid release (isolated "smoke or fume" events)? So it doesn't seem possible to work out the exposure to people, let alone the hazard of that exposure, from what has been found so far.
It could be high exposure and significant hazard, or low exposure and no hazard. More Research Needed, panic not justified by this evidence yet.

I Address this with new people...

Question:
Was flying better when smoking was allowed? Did they usa Oxygen Packs instead of bleed air? Someone in that link commented that their chest hurts more since the banned smoking...I hate smoke btw

from the Telegraph report:They seem to have forgotten to add, "and countless thousands of airline crew, both cabin and flight deck." :hmm:

Put it in the box with MMR vaccine and aspartame. How long have we been flying, how many people fly each day, how many crew have been working all of their lives on aircraft? :rolleyes:

before everyone gets on their high horse lets put this into perspective. Numerous 'studies' have been done - as a previous poster has said, no mention of concentrations, type of release etc etc. As these people obviously have an axe to grind i would assume that if any real scientific evidence of a problem were found then they would be publishing it far an wide. The silence on the hard data speaks volumes really.
Also one of the most vocal proponents of this problem that I used to work with smoked 40 a day, however was quite happy to keep trying to bash the company about this issue! This was clearly more of a political issue for him than a health issue.
Also how about some relative data - what is the air quality like sat in a traffic jam on the M25, or in a totally sealed airconditioned office (where most of the rest of the population work) eh? I bet there are equivelent risks everywhere.
I recently spent a week in a central asain city and came home with a cracking headache, and bad throat / runny nose etc. Bad cabin air? Nope - horrific polution and traffic fumes in the city. I know which parts of my job I'm more worried about and where I feel my health is most at risk - and it aint on the flight deck!

It's not all about the health of those onboard.
The symptoms of some fume events are said to include dizzyness, lack of co-ordination and loss of short-term memory. None of which are needed on a busy SID.

AAIB medical symptoms
 

For those who are STILL unaware of the type of medical problems that affect some crews - the following are official AAIB (Air Accident Investigation Branch - sic) descriptions of the medical effects on aircrew.

Passengers / customers don't count. Sorry.

The AAIB are not known for exaggeration and do not seem keen to want to face up to the reality of the issue either.

Unbelievable but true.

Aplogies for the length, but the evidence is ... overwhelming?

Extracts from actual UK AAIB (Air Accident Investigation Branch) reports.

All of these official statements are from different actual flying incidents and give an idea of the effect of the fumes on the flight crews.

• The pilot in command, following the onset of these fumes, had difficulty in concentrating on the operation of the aircraft, and suffered from a loss of situational awareness.

• …the crew had difficulty explaining the urgency of the situation (Aircraft diverted to Paris due to fumes and a smell of oil in the flight deck) to air traffic control.

• During the first flight the purser experienced an unpleasant feeling of fainting. She told the other two cabin crew members about this and they stated they had experienced something similar. They did not recognise any special odour.

• During the subsequent flight one of the cabin attendants who was placed in the forward part of the cabin experienced an odd pressure in the head, nasal itching and ear pain. The other two colleagues in the cabin also felt discomfort and the feeling of “moon walk” while working.

• The third flight the same day was flown by the Commander. During the flight, which took place at a cruising altitude of FL 280, all three members of the cabin crew experienced similar discomfort as during the preceding two flights but more pronounced. During the first portion of the flight the pilots did not notice anything abnormal but shortly before they were to leave cruising altitude the Commander began to feel a mild dizziness.

During the approach into Malmo/Sturup airport when the aircraft was descending through FL 150 the Co Pilot suddenly became nauseous and immediately donned his oxygen mask. Then, after an estimated period of ten seconds, the Commander also became very nauseous and immediately donned his oxygen mask. After a few seconds of breathing in the oxygen mask the Co Pilot felt better and thereafter had no difficulty in performing his duties. However the Commander felt markedly dizzy and groggy for a couple of minutes.
He had difficulty with physiological motor response, simultaneity and in focussing. Finally he handed over control to the Co Pilot. After having breathed oxygen for a few minutes even the Captain began to feel better and landing on Runway 27 without problems.

This incident was caused by the pilots becoming temporarily affected by probably polluted cabin air.

• All four cabin crew members reported feeling nauseous following passenger disembarkation, but they did not realise that they all had been similarly affected during the descent until the matter was discussed between themselves after landing. In addition to nausea, they reported feeling light headed and hot, but neither the flight crew nor passengers reportedly suffered any ill effects. The aircraft was reported to have had a history of such events and, despite satisfactory ground tests after this incident, similar symptoms were reported two days later by a different cabin crew when working in the forward galley.

• During the climb, the Senior Cabin Attendant (SCA) entered the flight deck to report that two passengers towards the left rear of the cabin had informed that they had noticed an oily/petrol like smell. In addition, a cabin crew member of a Company BAe 146 positioning crew had also reported a similar smell.

He (First Officer) sat in his seat but began to feel progressively worse, although his work load was low. He felt ‘light headed’ and had difficulty concentrating. He was aware of a tingling feeling in his finger tips and his arms started shaking.

At about this time the Commander also began to feel nauseous and asked the First Officer how he felt. The First Officer replied that he “felt dreadful” and the Commander looked at him and saw his face was white and that his pupils appeared dilated.

When she (SCA) arrived, the First Officer was on 100% oxygen, his seat was well back from the aircraft controls and his hands were seen to be trembling.

The Commander was feeling progressively worse. He felt light headed and recalled considering three aspects: landing, declaring an emergency and putting on his oxygen mask. However he felt able to cope only with one decision and continued his approach.

…the Commander seemed to have ‘double vision’ and had difficulty in judging height.

The Commander noted afterwards that it was all he could do just to land the aircraft as by now he felt very light headed and tired.

He (First Officer) did not consider that being on oxygen had made him feel better only after he had left the aircraft. However, he still felt as if he was in a daze.


• The crew noticed an “oily metallic” smell on the flight deck during an outbound flight from London Heathrow to Copenhagen. The same smell was noticed on the return flight. Towards the end of the flight, on approach to Heathrow, the crew missed numerous ATC calls, which prompted the controller to ask “if everything was all right”. In addition the Commander did not reduce aircraft speed to configure the aircraft for landing until reminded by the controller when the aircraft was at 3.7 nm DME (Distance Measuring Equipment). It was only after landing that the crew considered a possible link between the smell and their performance. When the smell was first detected, the crew had discussed the use of oxygen masks, but had concluded that there were no side effects to justify their use.

Subsequently, neither crewmember experienced any further symptoms or adverse effects.

• After parking on stand, both flight crewmembers experienced headaches and eye irritation.

• .….the Commander found it very difficult to concentrate on completing the fuel check and R/T tasks. He reported that his throat was dry, that his eyes felt irritated, that he had a headache and was generally aware that all was not well. The SCA reported that she also had a ‘very dry throat and eyes’ and the other crewmembers also had headaches.

• The Commander stated that, following the incident, he developed blisters inside his mouth, around his left inner cheek, on the roof of his mouth and left lower rear gum. He also had a tight chest, sore throat and suffered from coughing. The source of fumes was subsequently traced to No 3 engine, which was replaced on the following day.

• ……when fumes entered the flight deck and reportedly caused ‘dizziness and irritation to eyes’

However the problem recurred on 22 February 2001 when an oily smell was reported to have persisted on the flight deck for the duration of the flight, causing nose, and increasing throat irritation in both pilots.


• In addition to headaches, both pilots suffered from irritation to their mouths and nasal passages. An oily film was subsequently wiped off the flight deck CRT displays and passed to the operating Company’s engineering department for analysis.


• Both flight crew were left with a metallic taste in the mouth; the Commander also experienced a tingling sensation on his lips and a sore throat for several days. The First Officer was left with minor eye irritation.

• During the climb the Commander noticed a metallic taste coupled with an increasingly strong smell. The commander began to feel light headed and “un-coordinated”. The effects were still evident after landing with some reported errors of judgement and garbled speech.

• During the turnaround, the Commander alighted the aircraft in order to breathe fresh air but, after a short time, he suffered a head ache, itchy eyes, nausea and a bad taste in his mouth. The same crew then prepared the aircraft for return sector but, when engines number 3 and 4 were started, the Commander and the cabin staff felt increasingly unwell and as a result, the flight was cancelled. The aircraft was inspected in accordance with Service Bulletin ISB 21 – 150 but this did not reveal any oil contamination. However, following an air test it was found that engine No 4 and the APU were both the source of the fumes.

• The fumes reportedly affected two cabin staff and several passengers.

• The cabin manager felt overwhelmed by these fumes, and was on the verge of passing out, when her colleagues became aware of the situation and administered oxygen to her. After 10 minutes, the cabin manager recovered but was unable to resume her normal duties. Subsequent blood tests revealed that she had been exposed to higher than normal levels of carbon monoxide. (CO).

• The crew began to feel nauseous and so donned their oxygen masks, declared a PAN and returned to Heathrow where an uneventful landing was made.

• Then he started to feel dizzy and so donned his oxygen mask.

• The co pilot was limited in his capability of acting during the approach and landing due to the effects of fumes.

The medical examination of the co pilot after the flight showed that during the flight toxic exposure took place.

The medical examination of the Commander after flight did not show any results.

• They described it as a ‘burnt’ or ‘exhaust’ smell, but it was not accompanied by any visible smoke. Soon after, both crew members began to experience symptoms of tunnel vision, loss of balance and loss of feeling in the hands and lower arms. They immediately donned their oxygen masks, breathing 100% oxygen, which improved their condition noticeably.

• After a normal departure, and during the climb, the co pilot noticed a smell described as being similar to that of a central heating boiler. The commander, when asked by the co pilot, did not discern the odour.

Subsequently, the c o pilot complained of a dry throat and burning eyes. Control was handed over to the commander, shortly after which the co pilot experienced a tingling sensation in his fingers as well as complaining of being hot and sweating. The co pilot was placed on oxygen and the commander elected to return to Belfast. The co pilot slid his seat back and took no further part in the flight. The oxygen did not appear to be helping in the relief of the co pilot’s symptoms, although he remained conscious.

After an uneventful descent, approach and landing at Belfast, the co pilot was given first aid and began to recover. He was taken to hospital for further checks, including the taking of blood samples for later tests. Throughout the flight the commander did not suffer any ill effects and did not notice any smoke, fumes or odour.

Filter bleed air. It is NOT rocket science!

DB :{

People are dying from this stuff.

I remember 5 years ago or something, on the ABC there was a documentary or something, and they were discussing the toxic fumes in the aircraft etc, If I recall correctly the main aircraft that seemed to have the most problems with these cabin fumes was the BAE146 and Ansett used to have issues with the smoke....


Not sure if I'm recalling all this 100% accuratly, but did anyone else see/ remember something along those lines?

Panorama (BBC) recently aired a report on this as well, also involving the BAE146.
GUBA - Panorama - Something In The Air

Yes, that's correct. There had been a long series of reports/complaints by Cabin Crew about contaminated air in the 146s. I don't think anything was ever resolved. At that time I was regular pax between Perth and Tom Price in the 146. I really liked them, very comfortable.

Organophosphates are particularly dangerous and action needs to be taken to deal with the engine oil systems or filter bleed air effectively on those aircraft at risk. The effects of ingestion of these toxins has in the past caused legislation to protect farmers from sheep dips and the use of these toxins in nerve agents is hardly reassuring to airline crews.

I was fortunate throughout my flying career to fly types where oxygen use was mandatory for the duration of flight although airmix settings allowed one to whiff the fumes occasionally. I would want to use oxygen if I flew an at risk aircraft regularly.

Unfortunately, the elimination of risk is going to cost a fortune - watch the bean counters try to bury this issue.

10 years on....
 

Soddim,
You only need to read this newspaper article from 10 years ago to see how the bean counters have managed to bury this issue.

Guardian Unlimited | Archive Search

Might these be the same bean counters who are presently facing jail for screwing up the rest of the economy?

It seems to me that the first problem is the poisoning of innocent aircrew / customers.

The secondary and slightly worse / more worrying aspect is the joined up and on going cover up.

Who has heard of aerotoxic? Certainly not the people who are suffering from it!

But people aren't THAT stupid. They will work it out, it's just a matter of time.

Perhaps the German people can bring some fresh logic and common sense to the discussion...

Filter bleed air - it is NOT rocket science.


DB :ouch:

This telegraph report said that upto 200,000 pax could be affect every year. Sounds like a lot but to put that into context how many people fly per year ??? 500 million - 1 billion i don't know but it must be a lot !!

BIGBAD This telegraph report said that upto 200,000 pax could be affect every year. Sounds like a lot but to put that into context how many people fly per year ??? 500 million - 1 billion i don't know but it must be a lot !!

A lot of those "passengers" are business/regular flyers. In my current job I pax on 40 to 70 flights a year.

200,000 passengers affected is a lot and no matter the total of passengers that fly a year, 200,000 is 200,000 too many IMO

Simple answer.
 

Like global warming, there are lots of people who have a vested interest in this not being a real issue. Unlike global warming it would be a simple matter for the industry to get serious about some conclusive tests. They don't.

I've never been affected (to my knowledge) but now know a couple of people who are sure they have been & saner more balanced types I've yet to meet. What disturbs me is that there has been stock answer statements put out by those who are charged with our safety & regulation - and this includes manufacturers, pilot's union etc - for a very long time now.

The consequences of there being something serious in this are very big & where big consequences exist you usually find plenty of resources devoted to denial.

There will be many pax who are affected but have no idea how/when/by what or even what they have. Engine oil contains organophosphates - fact. It's a poison - developed by the Nazis to kill people - so go figure. How good are your oil seals??

What does seem to come out if you read these articles or saw Panorama is that most are not affected but some are and very badly. It needs looking at pronto before a crew becomes incap & kills a lot of people.

Unfortunately, sensible discussion of cabin air contamination was hijacked on this website last year by a group which appeared to have an axe to grind banging on about 'CO contamination', a very unlikely contaminant in a modern jet transport.
As far as I am aware the most likely source of contamination would be lub oil from a leaking forward compressor bearing seal.
I do not believe that I have ever suffered from contaminated cabin air but I did, at one time, have an ongoing lung problem. It was co-incident with spending long periods of time in Hong Kong.

People banging on
 

Unfortunately Basil, People tend to "Bang on" because nobody is listening to something they feel is important.

I agree it is often alienating when they do but to suggest that pumping poison round a jet engine whilst separating it from the cabin air by a simple oil seal (designed to work as a wet seal) does seem a little questionable to my simple mind.

so, "banging on" or not they may still have a point.

And no, I do not have any vested interest one way or another.............

I'm puzzled by this line in the Telegraph article :

"However, these “recirculated air” filters do not remove fumes or vapours from the engine. So if engine oil or hydraulic fuel leaks, toxic chemicals can contaminate the air supply."

The recirc filters (provided they are clean and serviceable) are capable of removing SARS virus and similar, suspended in the cabin air. How can they 'not' remove these chemicals ?
As I understood it from that BALPA Clean Cabin Air conference a few years ago, the much-maligned recirculation system is the only filtration system technically possible at the moment; once TCPs, pyrolytes etc have made it to the cabin the recirc filters will (eventually) remove them. I would have thought they'd catch toxic fumes too.

Human beings have a remarkable and irritating tendency to latch on to specific issues for dear life, while sweeping other issues under the rug. The level of concern people have for specific issues almost never correlates in any way at all with the actual importance of those issues. Perception is everything, and reality falls by the wayside.

The issue of "toxic" air inside aircraft is one example. Another, which I've encountered more and more recently, is the issue of "chemtrails," that is, the belief that condensation trails contain vile toxic substances in significant quantities, beyond water and carbon dioxide.

Still another example is the disparity in coverage of two recent accidents. After the first accident, the pilot in command was promptly canonized; after the second, much more recent accident, the crew is being posthumously vilified. And these attitudes have virtually nothing at all to do with the actual circumstances of each accident and the probable causes. It's all illusion.

It seems that all you have to do is put an idea into a person's head, and he or she will run with it, improvising and imagining all the other details along the way. Most people will in fact prefer the imaginary details to the real facts, even if you offer to give them the real facts, and the fewer facts that are available, the more intense and detailed the imaginings.

I doubt this is true, simply because more cabin crew and flight deck officers would be taking time off as they are sick? How many flights do Southwest do each day? And how many times have they been off?

Exactly what is in this toxic air anyway?

I hope I am not breathing in toxic air, mainly as my children would be doing the same. But I have never been ill, nor have them... Nor has anyone I know who flys a lot.

Nikolai.

Lots of people said the same about tobacco smoke.

They always know someone who smoked and lived to be 100.

Human nature
 

Exactly Moonraker.

Just because you can't see it nor touch it it doesn't mean it doesn't exist. Obviously there will always be conspiracy theorists but I don't think this issues falls into that category.

As I already said, the 2 people I know who fear they've been affected are simply not that sort. Asbestos underwent a similar denial phase with huge amounts of corporate resources thrown at denying any health risk meanwhile people continued to contract fatal diseases. It really is simple. The authorities have a duty to investigate ALL health risks that crews or pax may encounter in a pressurized cabin and it can be done fairly easily.

The more it isn't the more I think they have something to hide. There are too many sane people concerned about it now to simply say it's human nature to find single issues to whinge about.

jshg
 

The usual filters used in aircraft cabin air systems (made by PALL amongst others Clearing the Air on Airplane Cabin Air ) will not remove what are commonly (and incorrectly) referred to as 'fumes'. This is because the organic chemicals (like TCP/TOCP) are at a molecular level. The filters WILL remove dust and fibres (large particles) and maybe some oil mist which may have TCP dissolved in it or larger particles with TCP adsorbed onto it. Basically they are a micron-sized tea strainer. Organic chemicals and small oil mist particles get through. If you have ever seen a used filter you would see how well these things work (for dust).

The problem that you have with this issue is that not everyone is affected the same way: a proportion of the population are what the toxicologists call 'hypersusceptible', so it is difficult to know what 'acceptable' levels might be.


Pinkman

Re #20 “Filter bleed air - it is NOT rocket science”.
There are many problems: what are you filtering out, what is the contaminant / particle size? - see above.
What happens when the filter is full / blocked, if it subsequently fails do you expose people to a higher risk?

A quick look into many air-conditioning systems reveals a chemistry set consisting of old engine or hydraulic oil, de icing fluid, re circulated dirt/dust/detritus. What are the chemical processes that could occur with change of temperature / pressure / humidity during flight? How many of the serious events have occurred during descent – could there be a clue there?

A natural human reaction is to experience concern when encountering an unknown – the sense of smell can contribute a flee / fight reaction which in high stress situations / personal susceptibility (either personality or situation induced, e.g. fatigue) can contribute to actual or perceived physical deterioration. This is not to dismiss several well documented and as yet unexplained instances of crew incapacitation, but without knowing what the threat is, the range of defences might be restricted to reactive resources – use oxygen masks if smoke / fumes are encountered. Aspects of airmanship require us to control the stress of surprise – assessing the situation, protecting ourselves so that as crew we can fly the aircraft safely – rule 1.

GM Aircrew?
 

PE 3721,

You may be interested to know that there are many ex pilots, cabin crew who are absolutely certain and know 100% what caused their normal good health to alter for the worse whilst flying a certain four engine jet and other bleed air aircraft. Most still find out years later by mistake - NOT auto suggestion.

In contrast, we have various office bound doctors, lawyers, bureaucrats, regulators, politicians 'believing' (hoping) that toxic oil fumes in a confined space are not responsible for serious ill health.

Why do you think that the B 787 is bleed free? How is it that organophosphate deposits are regularly found in jet air conditoning systems and over internal surfaces? Why won't the UK Government tell the ex pilots which chemicals and concentrations are in the visible oil fumes from a cold APU start?

I'm sorry, but all of this is being logged (believe it or not) and when it is finally proved and after the scientists have finished testing Neanderthal man's DNA and other brain numbing equally usesless projects there will be heads rolling - and it won't be the pilots, I can assure you.

Last but not least, would finding oil deposits (including organophosphates) in ones blood / fat be a reasonable indication of a problem? Just like a drunk driver or a competetive athlete? That's what convinced me and many others, along with our serious untimely ill health.

Blood / fat check anybody? What happened to the precautionary principle, anyway?

I hope you agree that this is a black and white issue, no in betweens. Simple choice; Who do you trust - the vested interests or the GM aircrew?

KBO.

DB :ok:

And that's the problem: a lack of proper evidence/research. There should be no need to "believe" in anything: it should come from proper analysis of the situation. It's a bit like living next to a nuclear power station and "knowing" it gave you cancer - this is not science of any sort and unlikely to lead to any changes.

I fly jets with bleed-driven packs, so I am *very* concerned about air quality from a selfish point-of-view. I also have some sympathy for the technical side of the airline industry in that hard data on this subject seems pretty difficult to come by. I've seen a couple of papers but they effectively say: "more research required". Most of the "facts" I hear quoted are such things as "an engineer told me..." or "did you know that...", etc.

There is a temptation to go for a sort of conspiracy theory but considering that the airlines/regulators/investigators have been formally told of this issue on many occasions (and are running studies), it would be rather foolhardy of them to try and cover up something that is so much in the public domain, IMHO. Now that aeroplanes (in the UK at least) are covered under H&S, the sort of fines and lawsuits that would follow discovery of withholding of this kind of information would be spectacular, to say the least.

Also, I hear "just fit filters". What kind of filters are these and what are they filtering? Do they work or are they just like putting a hanky over your mouth during a nerve gas attack (which is the class of chemicals we're discussing). It'd be ironic if the airlines caved in and rushed out some countermeasures which were found to be ineffective some years later.

If I'm giving the impression that I'm unsympathetic to those who are suffering from ill health in their flying careers (possibly from some sort of nervous poisoning), then nothing could be farther from the truth. What I do feel is that we need less emotion and more hard science, otherwise we're just going round in circles.

Contaminated Air Reference Manual
 

Fullwings,

Good reply and well balanced.

The trouble is that this is not a balanced situation. If you and the previously mentioned vested interests actually took the time to look at the evidence, complete the studies and actually come to some conclusions - then we could all move on.

I take it you are already familiar with the well accepted vested interests tactic of 'never ending studies' to prevent a conclusion being drawn??

Boeing and BALPA know all about it. Boeing worked it out in around 1999 (hence the B787) and BALPA in 2005. It is now 2009 - 'on the balance of probability' Boeing and BALPA are both right. They are not stupid - nor are we.

I regret to say that any emotion stems from professionals losing their jobs, health, relationships as a direct result the ongoing denial. It's tough, I promise you.

David Learmount of FI was a famous non believer two years ago but he took the time to review the evidence of 40 years and called for filters.

Comment - Don't wait to take action over toxic cabin air

Now I don't agree with everything Mr Learmount says especially as I don't believe he has recently operated a Public Transport aircraft BUT he knows a lot about the shennanigans of the industry, he looked at the evidence and published his opinion. He would never have risked his reputation and that of FI unless he was absoultely sure of his facts.

Can I suggest you order the 800 page Contaminated Air Reference Manual and then cast your vote - maybe taking into account the Precautionary Principle.

I showed the manual to my AME and he unhelpfully said it was too long.....:ugh: (did I mention that the industry 'doctors' also have vested interests?)


Fullwings, as an ultimate 'stakeholder' Perhaps you would like to review the factual evidence and help come up with a well balanced conclusion?

Take care - in contaminated air. It's NOT good for you.

DB :ok:

Dream Buster, instead of yet another speech, please help share the answer to the reasonable question posed by FullWings: "What kind of filters are these and what are they filtering?"

I spent over ten years as a captain on the older 146 aircraft and although it had many good features one of it's worse ones was the quality of the air in the cabin pressurisation system. During the period I was flying it I suffered more colds and flu-like symptoms than at any other period in my life . I returned to Boeing 737 aircraft after that and almost immediately my health began to improve. Since retiring from flying and taking up simulator instruction about four years ago I virtually never suffer from colds or similar ailments at all! I attribute the extremely poor air quality on the 146 to two factors-
1. The high leakage rate through the engine oil seals into the bleed air.
2.The requirement to recirculate a high proportion of the cabin air to compensate for the inadequate thrust/bleed air from the engines (every 146 pilot knows how underpowered this aircraft is!)

Quite often apon initially starting a day's flying on the 146 it was common to start the APU and then select the highest possible cabin temperature in an attempt to try and "burn off" the residual deposits in the ducts before the rest of the crew and passengers boarded the flight!
Although the 146 and the Boeing 757 were known to be the worst offenders in the "dirty air" club I'm sure that eventually all new large aircraft will follow Boeing's lead and revert to indirect cabin pressurisation-- nothing new really-- the good old DC8 had cabin turbo compressors roaring away in the nose. (The downside of those was that most pilots ended up with with significant hearing loss!)

That's a big job, currently being worked on by far better qualified people than myself and I don't see a conclusion even on the horizon yet...

I've just ploughed through some of the reports from the CoT (a distillation of a small amount of what's out there) and it definitely reads like a work in progress. Many small studies of various factors but very little in the way of statistical significance - and that's the main issue, for me.

Are some aviation workers becoming ill with chronic nervous disorders? Yes. Are there 'fume events' occurring on some aircraft? Yes. Is there a causative relationship between the two? Not yet proven/disproved. Are we seeing a much greater incidence of these ailments than you would expect in a general population sample? Wasn't obvious from anything I've read.

'Control group', 'confounding variables', 'selection bias', 'significance level', 'blind trial'... These are the sort of phrases you hope to see when, say, a new drug is being brought to market and is undergoing toxicity testing. At the moment, much of what I'm looking at reads more like a sociological study because of the lack of empirical data.

One thing that did strike me (and others) is the fixation on TOCP synthesised from engine oils as being "the problem". I'd have thought a more holistic view was in order, given that we are operating in a wholly manufactured environment. There are plenty of possibilities for other neurotoxic compounds and vectors which may be being overlooked.

There are striking parallels with "Gulf War Syndrome" and it took long enough to come to some statistically valid conclusions - and that was with a 700,000 person sample with 1 in 4 affected! It was the Uranium shells, then it was the Anthrax vaccinations, etc. In aviation we're looking at something that is hovering around the noise floor: I saw a rough estimate of 3-15 thousand monitored flights on the 146/757 in order to gather appropriate data.

Maybe they did but I'd suspect the major drivers for an electric system would be decreased weight, cost, maintenance and fuel burn (all popular with the airlines).

Radiation, pathogens, nasty fumes, low humidity, epidermal bits floating around... An aircraft is a terrible place to be! But hang on, all these things are around at ground level, sometimes in much higher concentrations. Many have been environmental issues since the start of evolution. You can't take these things in isolation.

Just suppose that filters (activated carbon?) were fitted to all bleed-driven aircraft, 'just in case'. A wise move, in view of the 'precautionary principle', even though we don't fully understand the problem? It would make a lot of people happy and the industry would be seen to be 'doing something'. Imagine now that the problem wasn't what we'd thought it was but something else, equally as nasty, that had been overlooked... How long until that was found because "it's all OK now."?

I don't want to be a 'believer', I want to be convinced. So far I've seen very little that I could file under that heading but a lot from people with a very personal interest in the subject - and they don't generally make the best impartial researchers, it has to be said. No offence intended - just the ways things are.

Vertical Speed:

That is exactly the wrong technique. The smart thing was to start the APU and then run the pack(s) at Fully Cold for several minutes (regardless of how cold it already was in the cockpit/cabin) so that any possible sh*t went overboard before any heat was introduced into the system.

I never had a problem in almost 20 years and I am delighted to report that I am still in the rudest of health (so far anyway).