IS Forum
Forum Index Register Members List Events Mark Forums Read Help

Go Back   International Skeptics Forum » General Topics » Science, Mathematics, Medicine, and Technology
 


Welcome to the International Skeptics Forum, where we discuss skepticism, critical thinking, the paranormal and science in a friendly but lively way. You are currently viewing the forum as a guest, which means you are missing out on discussing matters that are of interest to you. Please consider registering so you can gain full use of the forum features and interact with other Members. Registration is simple, fast and free! Click here to register today.
Tags airplane issues

Reply
Old 19th December 2020, 10:48 AM   #1
The Atheist
The Grammar Tyrant
 
The Atheist's Avatar
 
Join Date: Jul 2006
Posts: 28,602
Please Enjoy Your Flight with Toxic Airways

This is something I've never given much thought to - beyond the fact that aeroplane air is lousy to begin with. (I could easily have been a nose as a career and to me, aeroplane air has a unique smell that always reminds me of The Langoliers - dead and stale)

I presume someone actually checks to make sure the air is airworthy - it is fairly essential for the operation of the plane - and never give it a second thought.

In fact, it seems that testing air quality on planes isn't just not done, it's strenuously argued against by manufacturers!

https://www.latimes.com/projects/tox...9-travel-woes/
__________________
The point of equilibrium has passed; satire and current events are now indistinguishable.
The Atheist is online now   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 22nd December 2020, 03:48 AM   #2
Mikemcc
Graduate Poster
 
Join Date: Dec 2009
Location: UK
Posts: 1,880
Two issues there:

Fumes from mechanical issues with the bleed air from the engines - easily spotted by the crew and can be fixed.

Particulates (including viruses in these more aware times). The air on a plane is largely recycled - the bleed air is to replace some that is vented out to reduce CO2 levels in the cabin. but it passes through HEPA filters, I don't know what grade, in the pharma industry we generally use H14 filters. Whenever we change them we test them using particle counters (used to use DOP smoke and photometers, but we've moved away from that). It's easy enough to test, up to the airlines to enforce test procedures.

https://www.caa.co.uk/Passengers/Bef...n-air-quality/

https://www.ustranscom.mil/cmd/docs/...rt%20Final.pdf
Mikemcc is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 22nd December 2020, 04:30 AM   #3
Planigale
Illuminator
 
Planigale's Avatar
 
Join Date: Jul 2013
Location: 49 North
Posts: 4,704
Originally Posted by Mikemcc View Post
Two issues there:

Fumes from mechanical issues with the bleed air from the engines - easily spotted by the crew and can be fixed.

Particulates (including viruses in these more aware times). The air on a plane is largely recycled - the bleed air is to replace some that is vented out to reduce CO2 levels in the cabin. but it passes through HEPA filters, I don't know what grade, in the pharma industry we generally use H14 filters. Whenever we change them we test them using particle counters (used to use DOP smoke and photometers, but we've moved away from that). It's easy enough to test, up to the airlines to enforce test procedures.

https://www.caa.co.uk/Passengers/Bef...n-air-quality/

https://www.ustranscom.mil/cmd/docs/...rt%20Final.pdf
Actually modern aircraft have good quality air (assuming as said above there is not a leak into the air intake. Modern jets have about 20 cabin air exchanges / hour probably higher at present. Isolation rooms in hospitals run at 10 exchanges / hour and operating theatres 10 - 20 exchanges / hour. So the air in aircraft is as 'clean' as in an operating theatre.
https://www.ncbi.nlm.nih.gov/books/NBK143720/
Planigale is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 22nd December 2020, 04:35 AM   #4
Darat
Lackey
Administrator
 
Darat's Avatar
 
Join Date: Aug 2001
Location: South East, UK
Posts: 97,844
Interesting last point in that article given the current times:

Quote:
...snip...

However, a report on SARS transmission on aircraft (29) showed that cases occurred among passengers seated further apart and on flights lasting considerably less than 8 hours, but the possibility that passengers who developed SARS were infected before or after the flight could not be excluded.

...snip...
__________________
I wish I knew how to quit you
Darat is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 22nd December 2020, 01:01 PM   #5
Myriad
The Clarity Is Devastating
 
Myriad's Avatar
 
Join Date: Nov 2006
Location: Betwixt
Posts: 17,636
Originally Posted by Planigale View Post
Actually modern aircraft have good quality air (assuming as said above there is not a leak into the air intake. Modern jets have about 20 cabin air exchanges / hour probably higher at present. Isolation rooms in hospitals run at 10 exchanges / hour and operating theatres 10 - 20 exchanges / hour. So the air in aircraft is as 'clean' as in an operating theatre.
https://www.ncbi.nlm.nih.gov/books/NBK143720/

Wouldn't air exchanges per hour per occupant be a better measure?

Isolation rooms in hospitals ~2 occupants, so 5 per person-hour
Operating theatres ~10 occupants, so 1.5 per person-hour
Airliner ~200 occupants, so 0.1 per person-hour
__________________
A zÝmbie once bit my sister...
Myriad is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 24th December 2020, 11:06 AM   #6
Bob001
Penultimate Amazing
 
Join Date: Dec 2006
Location: US of A
Posts: 13,018
Fumes may poison airline passengers.

More good news: Your plane may be gassing you.
Quote:
The air you breathe on airplanes comes directly from the jet engines. Known as bleed air, it is safe, unless there is a mechanical issue ó a faulty seal, for instance. When that happens, heated jet engine oil can leak into the air supply, potentially releasing toxic gases into the plane.

For decades, the airline industry and its regulators have known about these incidents ó called fume events ó and have maintained that they are rare and that the toxic chemical levels are too low to pose serious health risks.

But a Times investigation found that vapors from oil and other fluids seep into planes with alarming frequency across all airlines, at times creating chaos and confusion: Flight attendants vomit and pass out. Passengers struggle to breathe. Children get rushed to hospitals. Pilots reach for oxygen masks or gasp for air from opened cockpit windows.
https://www.latimes.com/projects/tox...9-travel-woes/
Bob001 is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 24th December 2020, 02:38 PM   #7
alfaniner
Penultimate Amazing
 
alfaniner's Avatar
 
Join Date: Aug 2001
Location: Sorth Dakonsin
Posts: 25,064
If it was dangerous or common we'd likely be hearing a lot more about it.

I was on a plane holding for takeoff once, and at one point a giant cloud of white vapor came through the vents. It wasn't unpleasant smelling, in fact, mildly sweet. There were a lot of surprised exclamations but no one panicked as far as I know.

The captain came on a moment later and said that the people de-icing the plane had sprayed too close to the intake vent. I'd think they'd have safeguards against that sort of thing. Well, maybe they do now.
__________________
Science is self-correcting.
Woo is self-contradicting.
alfaniner is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 24th December 2020, 03:32 PM   #8
Bob001
Penultimate Amazing
 
Join Date: Dec 2006
Location: US of A
Posts: 13,018
Originally Posted by alfaniner View Post
If it was dangerous or common we'd likely be hearing a lot more about it.
....
From the story it's indisputably dangerous. Airline crews and passengers have been hospitalized. The airlines claim it's not very common. The question becomes "how common does it have to be to be seen as a problem?"
Bob001 is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 24th December 2020, 03:47 PM   #9
TragicMonkey
Poisoned Waffles
 
TragicMonkey's Avatar
 
Join Date: Jun 2004
Location: Monkey
Posts: 59,746
The airlines just want you to pay extra for non-poisoned seats.
__________________
You added nothing to that conversation, Barbara.
TragicMonkey is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 24th December 2020, 04:07 PM   #10
theprestige
Penultimate Amazing
 
Join Date: Aug 2007
Location: Hong Kong
Posts: 50,639
Originally Posted by Bob001 View Post
From the story it's indisputably dangerous. Airline crews and passengers have been hospitalized. The airlines claim it's not very common. The question becomes "how common does it have to be to be seen as a problem?"
"Seen as a problem" in what sense? Obviously it's a problem. Also obviously, it's not happening often enough for the general public to have formed an impression that air travel is fundamentally unsafe and they should stop doing it.

I think the real question is whether the general public will form such an impression based on the LAT article. Everybody agrees that this kind of thing is a problem. And everybody also agrees that it's not enough of a problem to turn them off to air travel.

Does the LAT article happen to give a breakdown of incidents by airline? I suspect that the extent of the problem varies greatly with the training and maintenance of the various airlines. Like there are probably some airlines you don't want to fly because their pilots are poorly trained and their planes are poorly maintained. But the existence of those airlines wouldn't really justify a blanket, "air travel is more dangerous than you thought" type story.
theprestige is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 24th December 2020, 05:00 PM   #11
Trebuchet
Penultimate Amazing
 
Trebuchet's Avatar
 
Join Date: Nov 2003
Location: Port Townsend, Washington
Posts: 31,321
Just fly on a 787, they don't use bleed air.
__________________
Cum catapultae proscribeantur tum soli proscripti catapultas habeant.
Trebuchet is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 24th December 2020, 06:17 PM   #12
GodMark2
Master Poster
 
GodMark2's Avatar
 
Join Date: Oct 2005
Location: Oregon, USA
Posts: 2,211
Originally Posted by Myriad View Post
Wouldn't air exchanges per hour per occupant be a better measure?

Isolation rooms in hospitals ~2 occupants, so 5 per person-hour
Operating theatres ~10 occupants, so 1.5 per person-hour
Airliner ~200 occupants, so 0.1 per person-hour
You'd also have to account for the total volume of the room in that case, making it liters per exchange per person per hour (or similar). If you instead assume that the volume is roughly proportional to the number of occupants, you end up back using ((room volume/people) == 1) exchanges per hour. As the number of people is constantly changing (or at least not constant), while the room volume stays constant, that's a lot easier to calculate, while still giving reasonable results.
__________________
Knowing that we do not know, it does not necessarily follow that we can not know.
GodMark2 is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 24th December 2020, 06:38 PM   #13
Athyrio
Hipster Doofus
 
Athyrio's Avatar
 
Join Date: Nov 2006
Location: Nutsack, FL
Posts: 2,195
Aw, shoot! Those chemtrail barrels are leaking again.
__________________
Knowledge is good.... Emil Faber
Athyrio is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 24th December 2020, 07:11 PM   #14
Venom
Illuminator
 
Join Date: Apr 2011
Location: United States
Posts: 4,974
Originally Posted by Athyrio View Post
Aw, shoot! Those chemtrail barrels are leaking again.
Venom is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 24th December 2020, 07:23 PM   #15
Myriad
The Clarity Is Devastating
 
Myriad's Avatar
 
Join Date: Nov 2006
Location: Betwixt
Posts: 17,636
Originally Posted by GodMark2 View Post
You'd also have to account for the total volume of the room in that case, making it liters per exchange per person per hour (or similar). If you instead assume that the volume is roughly proportional to the number of occupants, you end up back using ((room volume/people) == 1) exchanges per hour. As the number of people is constantly changing (or at least not constant), while the room volume stays constant, that's a lot easier to calculate, while still giving reasonable results.

But the volume per person is not nearly constant, when comparing between an airplane cabin and just about anything else.* Do you really think the volume per person (with or without a nurse in the room) of a hospital isolation room is anywhere close to a filled up flight? "Assuming" it's the same greatly exaggerates the relative air exchange of the airplane.


*Exceptions: phone booths, porta-potties, WWII submarines, subway platforms and trains at rush hour, high school hallways between periods...
__________________
A zÝmbie once bit my sister...
Myriad is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 24th December 2020, 09:24 PM   #16
cullennz
Embarrasingly illiterate
 
cullennz's Avatar
 
Join Date: Sep 2006
Location: NZ
Posts: 20,030
Originally Posted by TragicMonkey View Post
The airlines just want you to pay extra for non-poisoned seats.
Lol

Sorry. But that cracked me up.

Lol
__________________
"I mean, you've got the first sort of mainstream African-American who is articulate and bright and clean and a nice-looking guy. I mean, that's a story-book, man," Biden said.

2007 https://www.nbcnews.com/id/wbna16911044
cullennz is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 29th December 2020, 01:11 PM   #17
CORed
Penultimate Amazing
 
Join Date: Dec 2008
Location: Central City, Colorado, USA
Posts: 10,144
Originally Posted by TragicMonkey View Post
The airlines just want you to pay extra for non-poisoned seats.
They're going to put in credit/debit card accepters and charge for oxygen masks. If that weird smell due to an oil leak doesn't convince you a little rapid depressurization will do the trick.
CORed is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 29th December 2020, 02:24 PM   #18
MRC_Hans
Penultimate Amazing
 
MRC_Hans's Avatar
 
Join Date: Aug 2002
Posts: 23,587
Obviously, keeping the air fresh in a passenger plane requires some kind of pumps that can take the thin air at cruising altitude and compress it to cabin pressure levels. Quite a lot of air. So, yes, whatever pump employed could fail and, among other things produce fumes.

Never heard of it in practice, though. Personally I have flown what equals twenty times around the world, and never experienced any.

Hans
__________________
Experience is an excellent teacher, but she sends large bills.
MRC_Hans is online now   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 29th December 2020, 04:46 PM   #19
Trebuchet
Penultimate Amazing
 
Trebuchet's Avatar
 
Join Date: Nov 2003
Location: Port Townsend, Washington
Posts: 31,321
Originally Posted by MRC_Hans View Post
Obviously, keeping the air fresh in a passenger plane requires some kind of pumps that can take the thin air at cruising altitude and compress it to cabin pressure levels. Quite a lot of air. So, yes, whatever pump employed could fail and, among other things produce fumes.

Never heard of it in practice, though. Personally I have flown what equals twenty times around the world, and never experienced any.

Hans
For most airliners (787 excepted) the pump is the compressor stage of the turbofan engine, which compresses a great deal of air to much higher than cabin pressures. You just bleed a little off and cool it down. That's why it's called "bleed air". The real trick is cooling it down, as it comes out of the engine rather warm.

You know when the air on airliners was far more dangerous than it is now? When they allowed smoking on board!

Then again, you might want to be careful. There might be as much as 50% Nitrogen in it!
__________________
Cum catapultae proscribeantur tum soli proscripti catapultas habeant.
Trebuchet is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 30th December 2020, 08:09 PM   #20
crackers
Muse
 
Join Date: Nov 2003
Posts: 811
I donít know what it is about the air in jets but as soon as I get in a jet I can smell it, and the smell of the air in a jet literally makes me nauseated. Every time.
crackers is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Reply

International Skeptics Forum » General Topics » Science, Mathematics, Medicine, and Technology

Bookmarks

Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT -7. The time now is 11:37 PM.
Powered by vBulletin. Copyright ©2000 - 2021, Jelsoft Enterprises Ltd.

This forum began as part of the James Randi Education Foundation (JREF). However, the forum now exists as
an independent entity with no affiliation with or endorsement by the JREF, including the section in reference to "JREF" topics.

Disclaimer: Messages posted in the Forum are solely the opinion of their authors.