A new study conducted by United Airlines and the Department of Defense has found that the risk of COVID-19 transmission onboard is virtually non-existent.
New Study By United Airlines Finds Virtually Zero Risk Of COVID-19 Transmission On Airplanes
The study, conducted by United and the DOD via the U.S. Transportation Command (TRANSCOM), claims to be the most “comprehensive” on cabin airflow completed to date and demonstrates that when a passenger is seated and wearing a mask, on average only 0.003% of infected air particles could enter their breathing zone, even when every seat on the plane is occupied.
The study occurred entirely onboard United Airlines aircraft and found that 1.) fast onboard air recirculation, 2.) downward designed air ventilation, and 3.) efficient HEPA filters make the cabin of a United airplane one of the safest indoor environments in the world.
How The Test Was Conducted
United explained how testing, formally called TRANSCOM/AMC Commercial Aircraft Cabin Aerosol Dispersion Tests, was conducted:
The research, which also involved the Defense Advanced Research Projects Agency (DARPA), was done by releasing particles across the entire cabin by section. Each section had 42 bio-defense sensors set up in every seat across multiple rows. Sensors were also placed in the galleys and jetbridge during ground testing. A mannequin (her name is Ruth!) equipped with an integrated aerosol generator was used to simulate breathing and coughing with a mask on and off. The sensors represented other passengers who could potentially come in contact with the particles emitted. To make the situation even more realistic, thermal blankets were used to simulate bodily heat emission onboard.
You can read the study here (.pdf).
Key Data Points Of Airplane Cabin COVID-19 Study
Key date points of the study include:
- Study took place over six months
- 300 tests conducted over 38 hours of flight time and 45 hours of ground testing on United aircraft
- Each test released 180 million particles – equivalent to the number of particles that would be produced by thousands of coughs
- The results showed that, when seated with a mask on, on average only 0.003% of particles actually made their way into another passenger’s breathing zone – the findings show that even in neighboring seats, risk is limited and that masks continue to help minimize exposure when someone coughs
- Approximately 99.99% of particles were filtered out of the cabin within six minutes due to fast air circulation, downward air ventilation and efficient filtration systems on the plane
- In addition to TRANSCOM, DARPA and United, study participants included Boeing, S3i, Zeteo Tech, and the National Strategic Research Institute at the University of Nebraska.
What United Airlines Is Saying About The New Study
Addressing the new study, United’s Chief Customer Officer, Toby Enqvist, stated:
“Throughout the pandemic, our top priority has been the health and safety of our customers and crew. It’s why we supported the work of military officials, medical experts and aviation engineers that shows that the cabin of an aircraft is one of the safest environments in the world. These results from the Department of Defense demonstrate that the steps we have taken at United, including maximizing air flow, running our air filtration system at all times, enforcing a mandatory mask policy and overhauling our cleaning procedures mean your chances of COVID-exposure on a United aircraft are nearly non-existent, even if your flight is full.”
CONCLUSION
I’ve linked to the study above and would welcome the commentary from scientists who have the time to examine the study, its methodology, and its findings. On the surface, this looks like incredible news that the risk of COVID-19 transmission onboard airplanes (at least United Airlines…) is near zero. Such a finding should bring more skeptical people back into the air and help move us toward a greater resumption in air travel.
Assuming no control group that was no-mask? Too bad, would be great to compare head to head so we could finally shut the anti-mask trolls up for good.
Or u could look at Yougov stats on mask use…then look at the case rise in all those countries.
Spain, France, Italy, Hungary (Ipsos) – all 80-90% mask use. Has it helped?
Even Malaysia at 90% – big wave now.
Denmark…meanwhile…low mask use…trending downward. Sweden – no masks…much slower
growth in cases – relatively speaking.
Meditate on this.
Masks don’t stop infections in surgery…many studies…well before COVID. I would NOT fly if I was worried.
But I’m not worried.
I have flown several times both local and international on no flight were food and beverages not served. Lets assume that everyone would would normally wear a mask properly (really a ridiculous assumtion) when they eat or drink the mask comes right off. So Here I am wearing my mask the person next to me is eating and drinking and starts coughing. So tell me do you think the airflow is now preventing me from breathing in any aerosolized Contaminants. Masks Have limited value preventing the wearer from breathing in contaminants only minimize spread. I fly now with an airplane sneeze guard bought on amazon. it works great and with the over head airflow no air from adjacent passenger gets close to me. Because it is just one sided my face is uncovered so in emergency I can apply O2 mask,
If everyone wears a mask is a BIG assumption to make. Was on a United flight last week and saw a couple people stroll on without a mask. The FAs just stood by and watched.
@UA-NYC what a [redacted by admin] comment “Assuming no control group…”. Just browsing the link to the study that was provided indicates they did.
Mask up, b*tches!
Can’t imagine an unmasked or poorly masked sneeze wouldn’t immediately spread into several other peoples spaces. Also this is sponsored by United. Not exactly an impartial third party.
It was not sponsored by United, but rather contracted to United by the federal government. United is the only airline with an intercontinental hub in the DC metro area and has the aircraft that the government wanted to test on. AA has no 767s and Delta has retired almost all 777s already.
But it’s in the blogger’s best interests to ignore the fact that everybody was masked, even when the blogger should know people take off the mask all the time even if they are initially wearing them. Just like United, the blogger has an interest in getting people thinking flying is safe.
Bingo.
This study will be ignored by 99.99% of people.
Show me a study that replicates real-world conditions: some portion of passengers are the a-holes without masks, masks down around their necks, worn as chin-straps, below the nose, or just removed completely while they “sip” their cup of coffee for 3 hours or eat one Pringle every 5 minutes on a long flight, all while smirking and feeling so proud of themselves.
I see these idiots out in the world every day, every single time I leave my home to go anywhere. Pretending that everyone is properly masked up (on a plane or anywhere else) is a fantasy – and it’s why we will be living with the pandemic for years (they’re also the ones who won’t get the vaccine).
The study indicates that the mannequins masks and UNmasked. Take time to read before you immediately be critical. No one wants to get COVID-19 but the amount of fear being pushed at people today is really disheartening and doing real damage to people. We need to keep a cool head, work together and move forward.
Not enough information to make a conclusion, sorry.
0.003% might mean that 600,000 virus particules results in 20 virus particles after one pass. But can 20 virus particles give you Covid-19? Another thing is that I was once on a United flight to IAD sitting next to a coughing passenger. Sitting in an aisle, I tried to face the aisle during as much as of the flight as possible. I caught the cold, a really bad one. The common cold is caused by a species of coronavirus, the same family as Covid-19.
My own personal opinion is that air travel creates real hazards. Much of the hazard is from before and after the trip. Ground transportation, TSA, gate area, aircraft, etc.
My own personal opinion is that President Biden or soon to be former President Trump will not improve the situation. You may or may not like him for other reasons but he will not save more people from Covid-19. That task is our own responsibility.
What do you suggest as a path for moving forward, noting that we cannot remain shut down forever and life must return to some semblance of normality?
I suggest that airlines continue to fly to meet the demand. Some people have to travel to LAX or JFK or CVG, etc. But look after yourself. Nobody is going to think twice if you’re dead (Matthew is an exception; I would mourn his loss and this column even if Kyle took over).
What this does is that it kills restaurants unless there are enough stupid and reckless people (sorry for being blunt). One should eat out only if absolutely necessary, which means very rarely. Politicians cannot say this (EXCEPT Biden, who in an earlier possible pandemic that didn’t actually take place to stay away from planes and trains….he did say that!!! Funny but true)
Younger people have to know that they are not immune but the chances of dying are lower. So younger people can do the errands for older people, like going to the grocery store.
The new normal for 2021 and 2022 is to act as cautiously as you should be doing even with a vaccine. That will be normalcy. The way it was in 2019 may never come back or it might take until 2025 to come back. Spanish Flu in 1918 lasted a few years, not just a few months. A doctor told me respiratory virus just don’t go away. They will linger or spread like wild fire. Ugh.
https://www.reuters.com/article/us-biden-flu/biden-would-avoid-subways-planes-after-swine-flu-outbreak-idUSTRE53T43O20090430
Biden would avoid subways, planes after swine flu outbreak
(Reuters) …“I would tell members of my family – and I have – I wouldn’t go anywhere in confined places now,” Biden said on NBC’s “Today” show.. “It’s not that it’s going to Mexico. It’s you’re in a confined aircraft. When one person sneezes, it goes all the way through the aircraft. That’s me. …
“So, from my perspective, what it relates to is mitigation. If you’re out in the middle of a field when someone sneezes, that’s one thing. If you’re in a closed aircraft or closed container or closed car or closed classroom, it’s a different thing.”
That contradicted more restrained advice from President Barack Obama and the federal government – and the last thing the White House wants to do right now is shut down the airline industry and big city subways out of mass panic.
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Disclaimer. This is not an anti-Biden comment. It is a comment that a politician wouldn’t usually make but that parents might comment to their kids about.
It’s about time the added extra air change rate of aircraft cabins, and the efficacy of the HEPA filters used in the air recirculation system, was highlighted as a huge mitigating factor in making air travel safer than being in a bar or similarly congested venue. However.. as the aviation world’s premier devils advocate I must point out, after reading the study, that one important variable, although admitted, was not tested. Cabin crew and passengers moving about produce turbulent air which would critically affect the airflow dynamics (ask your self how often the aisle is empty). Another point is that the statement that “Overhead gasper supply (on or off) does not make a significant impact on aerosol risk” is just not born out by the figures in the charts and has been highlighted as a pathogen spreader in at least 2 previous studies. Apart from these two points this experiment seems like a great step forward in reassurance. My patent pending aviation covid mask system would however keep you 100% safe during flight.
Hahaha. Hahahha. Hahahah. Hahaha. Tell that to the 16 business class passengers flying from Vietnam to England. Or his air force 1 probably played a role in infecting dozens of Trump’s staff.
This is ridiculousness of proxy of proxy of proxy of surrogate of another surrogate data to goal seek data.
Once again, it’s the stupid “second hand smoke is more dangerous than smoking, because the smoker has a filter” argument with a ridiculous experimental design, ten steps removed from reality, to support an argument that will be disproven over and over as people have the time to do the contact tracing on specific flights and outbreaks. And yea, people don’t always wear masks and the boarding area is toxic.
Please don’t give platform to nonsense. Please don’t amplify nonsense.
no way you are comparing the flight back in March to the standards in place today?
No way I am comparing CPAP machines strapped to chairs as a surrogate for human transmission either.
Hmmm…. study sponsored by United Airlines find a very small risk, study described as independent by the BBC finds 70 to 100% chance of catching the virus if either side or in the row front or behind a contagious passenger. I know which one I am believing, and as others say there are enough “idiots” in the world who think the rules, like wearing masks, are for others to follow, but not them, we are all still in trouble.
I am really disappointed in the WHO, world governments, infections disease experts etc that the world was not better prepared for this…. billions of masks should have been in stockpile, Ford & GM already had the blueprints and bill of materials for ventilators in there manufacturing system etc. If everyone in the world had “stood still & kept clean” for 2 weeks at Christmas time the virus would have died out, problem fixed back in January.
If you believe anything the BBC broadcasts it’s time to come out of the rabbit hole.
Covid doesn’t kill everyone with a grandma on a plane? WEIRD??
Covid doesn’t kill most everyone it touches?? SHOCKED!
It’s amazing how much fear and brainwashing is on display on the internet.
As an American 3 months into a 18 month round the world trip – 100,000+ airmiles this year and 5 continents, you all need to grow up and learn to use your brains.
‘Mask up?’ Lol, what are you people, first graders?
Are you the same people that want kids to wear helmets when they walk to school?
What a waste the internet is. Just a bunch of people parroting idiotic ideas that someone else told them.
Grow up, learn to live your own life, and stop telling others what to do.
There is an amazing world to explore out there, and anyone with a brain can see through the BS being sold to the world.
Think for yourselves. Life is a lot harder than screaming at strangers on the internet about a weak corona-virus.
Sheesh.
OH Thats great! BUT I still REFUSE to gamble with my life with covid-19 air at airport, etc.
Had to laugh at the “fast moving air” part. Just flew a United CRJ DEN to MTJ Tuesday. Not only was the air not moving fast, there wasn’t any. One of the hottest, most uncomfortable flights in recent memory. The study probably is true of some newer planes, but certainly can’t apply to all.
Years ago I was on an international flight (US carrier) and I can’t sleep on flights. It was mostly dark except for some overhead lights. I was tired but noticed something moving through the air and it took me a few seconds to realize what had happened. Someone in a row or more behind me had sneezed and the light reflected off the particles as they went by. Pretty disgusting.
I’m not sure this makes any difference economically since much of the world is closed to travelers, especially from the USA.
If we could be teleported to the jet and everyone masked up – this would be correct.
…but there is the Uber to the airport. Maybe a hotel? Oh and don’t forget about check-in. TSA. Then the gate area. Landing and the same again.
Yes we can in fact choose to 100% shut down. We could lock down for two weeks – 100%. Bug would be gone. Will it happen?
No.
This is why I am planning to all but shelter in place until it is safe to travel once again.
Just not worth the risk to my life and those I love.
Even the experts don’t say “the bug would be gone” if you locked down. Because even “locking down” means millions of people are growing, packaging, making, transporting, stocking, picking up, and delivering your food, medicine, and essential goods, keeping your water, gas, electric, and internet running, manning the fire and police stations, keeping hospitals, clinics, nursing homes, and urgent cares open, running gas stations, repair shops, pharmacies and public transportation and rideshares and taxis and airports and harbors that make possible the fact that you can “lock down.” And that’s the absolute best-case scenario. The arrogance in your post is astounding.
“just not worth the risk to my life and those I love” in the above comment.
I agree. I mourn not being on a flight. I loved being on planes. The fast TSA PreCheck, looking out the window, getting work done on the plane, liking the destination even if was mostly work and almost no play. I loved being elite status on airlines and hotels. I want to fly again but my logical side of my brain says, “you want your 90 year old Grandpa to cough and die?” No! So I am doing this for Grandpa and others’ Grandpa….and myself. I suspect I got Covid-19 in August but my test was just as symptoms started so too early to be accurate. I was sick the entire month of August and not completely well for 2 weeks in September. Now I learn it may be possible to get sick again because there is possibly not lifelong immunity.
I suspect I got sick at Best Buy. I wore masks but I think I went too late in the day when hundreds of people already had gone into the store and coughed. Now when grocery shopping, I shop when the store opens at 6 am. Safeway opens at 5 am so if I am shopping at Safeway that week, I am there at 5:02 am. Ugh. (but if I get sick, Biden or Trump is not going to send flowers)
Good, one less sucker I have to compete with for award space
It’s like driving drunk. If you drive drunk, you will probably get home. At most, a little scrape on your car but even that doesn’t happen. Why then all the fuss from MADD? Covid-19 is no laughing matter. It’s not “like the flu” because the season influenza A does not kill 218,000 Americans. If people just act properly, Covid-19 could be nearly over in a month. In Singapore, they did that. They still wear masks to prevent another wave but they managed to get only a single digit of cases every day (equivalent to 150 cases a day in the US if population is adjusted).
I took a look at the study and it has a flaw in its methodology. The study only looked at United 767 and 777 aircraft, both of which are twin-aisle aircraft. Therefore, the results may not be applicable to single-aisle aircraft and twin-aisle aircraft configured by different carriers
I think this United-DoD study was well-conducted for what it was intended to simulate, but the results are being presented in a disingenuous and irresponsible way by United.
It not only assumes that everyone is masked, it further assumes that everyone is wearing their masks correctly, fit reasonably well above the nose and tucked underneath their chins, AND that everyone is going to keep their masks on throughout the duration of the entire flight. As someone who has traveled during the pandemic, you know very well that a very significant percentage of people wear masks under their nose, wear neck gaiters that are open under their chins, or take masks off for more than the recommended 10 minute maximum for food and drinks.
We ALREADY knew that planes are extremely safe environments when everyone is masked. Because of the high rate of top-to-bottom air circulation and HEPA filters, airborne transmission via aerosols is virtually nonexistent, so the main mode of transmission is larger droplets within the immediate vicinity of a cotagious person (up to those seated approximately two rows or seats apart). Masks cut the projection of larger droplets by an order of magnitude when measured at the typical distance between seated passengers. The remaining single-digit percentages of larger particles would quickly be pushed to the ground by the airplane’s ventilation system. All of this is perfectly consistent with what we already know about this virus.
The main risk is that one infected person will remove his mask for more than 10 minutes to enjoy a beverage, and infect ten people in his immediate vicinity. This risk is only partially mitigated by everyone else wearing masks (since masks protect others more than the wearer), not to mention that those others might also take off their masks. Right now, personally, I do not travel by plane unless I have a tightly sealed N95 mask on throughout the entire duration of the flight. But that is not a recommendation we can responsibly give to others, because we still don’t have that many N95 masks due to insufficient mobilization of production from the nation’s public health task force, and we should be reserving those for medical professionals (I just happened to have a few industrial N95 masks in my laboratory remaining from prior work with toxic chemical fumes). So let’s start with hundreds of millions of N95 masks. The tiny country of South Korea is producing 160 million KF94 (N95 equivalent spec) masks per week because their government mobilized the entire nation’s industrial manufacturing capacity to provide enough masks for the public; it’s totally possible for the United States to do the same. We also really want to vastly increase rapid testing capacity to screen travelers, obviously.
If I had to guess the risks of COVID-19 infection from getting on a plane right now, I’d still start with that previous MIT study that estimated 1/4300 with filled planes and 1/7700 with middle seats blocked. That study also assumed that everyone was masked, but had more realistic real-world rates of failure or non-compliance estimated based on empirical data. However, given that the ongoing COVID-19 infection rate is currently almost twice as large as when that study was published, I’d roughly double those numbers.
Very helpful comment. Thanks for taking the time to so clearly write out your thoughts.
Would approved KN95 masks, in reasonably good supply in the U.S., be a decent alternative if one is on an airplane?
Since you specified “approved” KN95 masks, I am assuming that you mean those that have emergency use authorization from the FDA. In such cases, I would say yes. Just to lay out a few caveats:
1. There is a study saying 70% of KN95 masks in circulation do not meet the requisite specifications, so there seems to be a quality control problem. Make sure it is from one of the reputable manufacturers.
2. I’ve noticed that a significant percentage of KN95s in circulation seem to have valves, and those are banned by many airlines since they don’t protect others if you happen to be infected. Quite unfortunately, these include a good fraction of those that the Chinese government sent out as goodwill gestures or to provide protection for their own citizens abroad.
3. The way these KN95s are shaped often makes for a poor fit on certain facial shapes. The fabric forms a triangular shape above the nose and it is too stiff for the embedded wire to bend it enough to give you a good seal around the nose. This is particularly a problem for caucasians, who tend to have longer noses than Asians.
I have personally been using KF94 masks (Korean N95 equivalents), and have been giving them to all my older colleagues. They also don’t provide as tight a seal as a medical grade N95, but on average they seem to fit many people better than KN95s. The quality control is also significantly better. Unfortunately the South Korean government instituted a ban on KF94 exports when their outbreak got bad, so the ones that are circulating in the US usually sell for about twice the price of the KN95s. I personally still think it’s worth it. There are also European equivalents, but those are even more difficult to get…
https://www.reuters.com/article/health-coronavirus-airlines-risks-int-idUSKBN27412C
‘Bad math’: Airlines’ COVID safety analysis challenged by expert
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personally could care less…I’ve already flown and taking my first int’l flight since Feb. If u understand health…
no worries.
If I didn’t…I might not fly, let alone on a long flight. But then there’s a lot of other things I wouldn’t do either
if I didn’t either.
OH yeah…Check YouGov mask wearing % for Spain, France, & Italy. Now go look at their case spikes….
People can eat/drink on flights…did they test for that?
It’s a flawed study.
https://www.reuters.com/article/us-health-coronavirus-airlines-risks/bad-math-airlines-covid-safety-analysis-challenged-by-expert-idUSKBN27411C?fbclid=IwAR3C2VAvF_McBKRdGDXeOUV_ryb1rJH9-rqFa47_HYhKKlxn0aKDUTW3fCU
Dr. Freeman, who is cited in this study said:
“It was bad math. 1.2 billion passengers during 2020 is not a fair denominator because hardly anybody was tested. How do you know how many people really got infected?” he said. “The absence of evidence is not evidence of absence.”