Back to Squawk list
  • 24

United Airlines Makes Changes To Air Filtration System As Travelers Grow Comfortable With Flying Again

One year after the COVID-19 pandemic brought the airline industry to a screeching halt, some have said flying has never been so clean. Though Denver International Airport is still operating at a drastically reduced capacity compared to pre-pandemic numbers, United Airlines said they’re slowly but surely returning as time continues. Matt Miller, Vice President of the United Airlines hub in Denver, said United is currently operating at around 50% regular capacity. That number continues to rise as… ( 更多...

Sort type: [Top] [Newest]

darjr26 6
This seems like old news. Speaking of old news I flew on a United flight in the 60’s that gave you a small pack of cigarettes with their meal service. They even had United’s logo on it. TWA did the same thing. I still have both packs. I’m not allowed to smoke.
victor carreno 2
In 1988, President Ronald Reagan signed a law making smoking illegal on all domestic flights of two hours or less...
G B 2
I just want to know how often the HEPA filters are changed. Every article I've read up to now never mentions it!
Dan Grelinger 1
HEPA filters don't need to be changed very often. Unless damaged, nothing gets through them, no matter how long they have been in service. In fact, HEPA filters get more effective at removing particulate from the air the longer they are in service. HEPA filter lifetimes are determined by the pressure differential across the filter. As the filter traps particulate, the pressure across the filter rises and/or the air flow through the filter drops. In clean environments (like semiconductor clean rooms) HEPA filters are rarely replaced. In many environments, air is passed through a pre-filter (much like the one in home heating-A/C units) that prevents the larger particles (dust, lint, dirt) from even getting to the HEPA filter, in order to lengthen its lifetime.
user3956 1
Regardless of how they work, or what the mechanism for determining replacement is, the question evolves into something like, "are they replaced often enough so that the filters in place are always effective" etc.

For instance, you wouldn't want the same filters in place for 100 yrs. What is the length of time - at the air pressure differentials utilized in this implementation - that these filters are effective considering the fact the fact that they are indeed getting clogged up constantly with various particles.

Are they effective for 3mo? 6mo? 1yr? And whatever that timeline per the pressures being used and the clog-rate being experienced sufficient to know that they are still working as intended to filter the air per HEPA definitions etc.
Dan Grelinger 1
Effective really means more than just the property of removing particulate from the air. It includes providing for a reasonable pressure drop, which directly influences the airflow. Unless damaged physically, HEPA filters 'fail to be effective' when the pressure drop rises to the point of compromising airflow. Effectiveness is reliant upon the amount of particulate reaches the filter (air volumes treated x particulate density). I am not familiar with airliner filtration systems, but in semiconductor manufacturing cleanroom HEPA filtering systems, pre-filters were installed (and routinely changed), and they are effective at removing a very large percentage of particulate mass that would fill the HEPA filter. Pre-filtering rendered the required change intervals to be pressure differential triggered, not time triggered.
user3956 0
The question remains, in these implementations, how long on average is a HEPA filter effective and at what interval should they be replaced -> are they being replaced at those intervals? This is the question people are asking.
Terryjp 3
The 1988 smoking ban was a result of the Air Canada bathroom trash fire/tragedy. It had nothing to do with public health except preventing the same thing from happening again.
Dan Grelinger 1
It would seem that the practice of putting smoke detectors in airline bathrooms (as was actually done) would have been effective at eliminating bathroom trash fires.
skylab72 1
Nope, that just tells you when you have the problem. It does nothing to mitigate the problem nor issues caused by the problem.
Dan Grelinger 1
"Nope". You're not considering the preventative effect of the very visible smoke detector in the bathroom.
skylab72 2
True, both that I was not thinking about the preventive effect, and that it is quite real, I was thinking about having observed clandestine smoking elsewhere even with smoke detectors in the restrooms... point well taken.
mary susan watkins 3
just a several years back, the airline eliminated smoking on airplanes for health and safety concerns,redoing the air filtration systems on aircraft is an excellent idea,especially if ual and other carriers want people to return to flying and feel safe..
matt jensen 1
geez, long overdue
Paul Thomas 1
If I read this right, all they're doing (did?) is change the operation of them (running them through boarding and deplaning, not just in flight) vs. actually changing the system itself, correct? i.e. misleading headline?

[This comment has been downvoted. Show anyway.]

Bill Brehm 14
It's been a while but not 50 years yet. My first flight was 43 years ago and there was smoking then and for some time afterwards. Well let's check...

"In 1988, airlines based in the United States banned smoking on domestic flights of less than two hours, which was extended to domestic flights of less than six hours in February 1990, and to all domestic and international flights in 2000."
Alan Glover 2
Not everything on wiki is wrong but they get enough of it wrong that I use specific sources related to the subject, not a publicly edited entity that has many controversies regarding editorial censorship.
dj horton 7
Prohibiting smoking on flights had nothing to do with health and safety. The problem with smoking was the particulates in cigarette smoke clogged outflow valves and prevented them from working properly. They were both an expensive and time consuming maintenance event.

And no way was it 50 years ago.
Jan Rio 3
there was smoking allowed on flights to France and Canada from the US in 1997, possibly even 2000.
user3956 2
I was on a Việt Nam airlines flight in 2013 which still had ashtrays. Most likely the smoking ban had been in place in Việt Nam for a while already but it was still shocking to see ashtrays on a plane, something I hadn't seen since I was a kid.
Peter Koranyi 1
I am only a passenger but I think I read somewhere (on this website?) that the ashtrays in the bathrooms are still there so that IF someone was illegally smoking in there they would have a safe place to extinguish the cigarette. But I suppose dousing it with water from the sink would work too...
user3956 1
I mean there were ashtrays in all of the armrests - like old times in the US. I didn't go to the restroom on that flight because it was super short from Sài Gòn to Quy Nhơn.
wtwisniewski -7
To end this pandemic, we need to eliminate as possible breathing air that was already breathed by someone else. I would like to see the FAA put ADs on passenger aircraft requiring large flow air filtration or outside exchange supplied to all occupants. No, the pandemic is not over, and the next one may be far worse. We failed to heed warnings that this would happen and designed cabins with minimal air flow thus promoting the spread of viri and other pathogens. Don't share the air!
Dan Grelinger 4
There is really only one way to NOT breathe air that has ever been breathed by someone else...
Steven Nolen 5
The entire airflow of an airliner is filtered to over 99.9 percent and completely refreshed every 3 minutes. Short of standing outside you’re not going to get fresher air.
Alan Glover 1
Whatever you do, do not live in fear. It only gives the authorities more reason to exercise their undeserved power.

Live free or die.
user3956 0
"Viri" is not a correct plural of "viruses" and was spread falsely as such with regards mostly to computer viruses.
Rex Bentley -4
Barnum was wrong, there's more than one sucker born every minute.


还没有帐户吗? 现在就注册(免费),设置诸多自定义功能、航班提醒等等!