Contaminated Cabin Air

Very interesting. On my commute home yesterday the guy next to me said something about smelling feet right after takeoff. I didn't smell it but it sure sounds like what the guy in the video is describing.
 
There have been several crew members killed or severely disabled due to cabin fume events. Mostly it's atomized fuel or oil, but sometimes hydraulic fluid that ends up in the packs and then the cabin.
 
It’s never a good idea to take any chances. If you think there’s even the smallest risk of contaminated cabin air, immediately get the junior cabin attendant to collect a sample with a spare trash bag and bring it up to the flight deck for analysis. Safety first.
Nice!
 
There have been several crew members killed or severely disabled due to cabin fume events. Mostly it's atomized fuel or oil, but sometimes hydraulic fluid that ends up in the packs and then the cabin.
It's always oil unless MX makes some huge mistake that should have been detected wasn't during ops checks. The air coming into the cabin comes from the compressor, before fuel has been introduced. If an oil seal in the compressor fails on an engine or an APU you're likely to get odor in the cabin. I've never heard of hydraulic fluid fumes being an issue outside of the hangar. If you'd like to experience skydrol in an atomized state go hang with the MX guys on pretty much any Gulfstream, the 200 being the worst, when they have to reset the landing gear shuttle valves after an emergency blowdown functional test.
 
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I've always found it interesting that passengers haven't really ever been effected by these 'events'. I'm not doubting they occur but it's generally only crew that complain and get sick.

I have a hunch that the 787 was developed with electric air compression because of this issue however.
 
I've always found it interesting that passengers haven't really ever been effected by these 'events'. I'm not doubting they occur but it's generally only crew that complain and get sick.

I have a hunch that the 787 was developed with electric air compression because of this issue however.
I would say once about every 6 months or so you hear on the news of a handful of pax getting sick from a fume event. Likely happens more than we actually hear about it. But I agree, in the extreme cases it seems to only affect the crew.
 
I've always found it interesting that passengers haven't really ever been effected by these 'events'. I'm not doubting they occur but it's generally only crew that complain and get sick.

I have a hunch that the 787 was developed with electric air compression because of this issue however.
I'd suggest the recent event with an SWA APU at KSNA.
 
Let me know when someone has a peer reviewed medical or scientific study of any type that they can cite about pack contamination deaths.

Exxon and BP have published data for years about inhalation of various hydrocarbons and organophosphates. You can look at the MSDS for any sort of oil or gas they'd load into an airplane and get a sense of what you are dealing with.

As far as studies related specifically to atomization due to the pack system... There's a fair number of research projects both from academia and from various country's multi letter aviation organizations. I'm attaching two here. One is a doctorate project from Norway that is an overview of the studies conducted (among other things) and the other is from the BFU (German equivalent of the NTSB).
 

Attachments

Exxon and BP have published data for years about inhalation of various hydrocarbons and organophosphates. You can look at the MSDS for any sort of oil or gas they'd load into an airplane and get a sense of what you are dealing with.

As far as studies related specifically to atomization due to the pack system... There's a fair number of research projects both from academia and from various country's multi letter aviation organizations. I'm attaching two here. One is a doctorate project from Norway that is an overview of the studies conducted (among other things) and the other is from the BFU (German equivalent of the NTSB).

As you said the first paper you linked was an overview of the state of research on the subject and didn't have much content to it. The second pdf discusses fume incidents (I'm not arguing that fume events never happen), but under their long-term effects section they state:

"A classification of these incidents as accident in accordance with Regulation (EU)No 996/2010 was not possible, because the legal definition of a serious injury does not include long-term illnesses or illnesses which occur later. In addition, a causal connection between the illness and the described fume event would have to be established."

So that is why I find claims about chronic illness being caused by this to be a non-starter until someone proves a link.
 
So that is why I find claims about chronic illness being caused by this to be a non-starter until someone proves a link.

There aren't many studies directly related to aviation fumes exposure that you'll find, mostly because the organizations (OEM/airlines) that have money to fund a study are really concerned about what the results would be. There are a few, but mostly you have to look at other industries (mostly petrochemical) that have similar exposure potential and see what's been done there.

This book (kind of pricey though) has a whole chapter that correlates exposure studies from other industries with cabin exposure and discusses both long term and short term effects.
 
I've always found it interesting that passengers haven't really ever been effected by these 'events'. I'm not doubting they occur but it's generally only crew that complain and get sick.

I have a hunch that the 787 was developed with electric air compression because of this issue however.
I would guess it would have more to do with fuel burn. Bleed air robs an amazing amount of power.
 
Back at ASA the mechanics used to just say the wet sock smell was ‘dirty packs’ and ‘y’all be fine’. I wonder how much of this crap I’ve been exposed to over the years and whether it’s had a cumulative effect?
 
Back at ASA the mechanics used to just say the wet sock smell was ‘dirty packs’ and ‘y’all be fine’. I wonder how much of this crap I’ve been exposed to over the years and whether it’s had a cumulative effect?
There might be a reasonable explanation for the "wet sock" smell. In many airplanes the air coming out of the packs is routed through a water separator, inside of the water separator there is a coalescer (basically a sock stretched out over a metal cone). They get changed on a regular basis, but it's like putting all of the cabin air through a dirty sock after any number of cycles. Your airplane might have dirty socks, ask MX to change them, then duck before you get hit by any number of flying solid objects.
 
I would guess it would have more to do with fuel burn. Bleed air robs an amazing amount of power.
It would be far more efficient to use the already produced bleed air vs use that energy to generate electricity to compress it again.

Compressing air via electricity is incredibly inefficient, look at a large air compressor running an air tool - to run a DA continuously requires at least 5 hp, to run the same tool on electricity requires maybe 5 amps which is around 0.75 hp.
 
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