Share this page!

Enter URL or ID to Unroll

You can paste full URL like: https://x.com/threadreaderapp/status/1644127596119195649
or just the ID like: 1644127596119195649

How to get URL link on X (Twitter) App

  1. On the Twitter thread, click on or icon on the bottom
  2. Click again on or Share Via icon
  3. Click on Copy Link to Tweet
  4. Paste it above and click "Unroll Thread"!
  5. More info at Twitter Help
Joey Fox Profile picture
@joeyfox85
Jul 7, 2022 • 19 tweets • 6 min read • Read on X
Reducing COVID Risk While Flying

Going on a trip? Want to avoid getting COVID? Follow these steps and you can significantly lower your risk.

1/13
You will have no control over many of the places you will be. Your best line of defense is a N95. It needs to be properly fit. Some places will be very high risk and a poorly fitted respirator might not be good enough. Do a seal check.

2/13
cleanaircrew.org/masks/#How_to_…
Getting to the airport

If you're in a taxi, wear your N95 and keep the windows down. “For driving below 30mph (48kph), opening all four windows is most beneficial.
But on faster roads, opening two on a diagonal can have an even bigger impact.”

3/13

bbc.com/news/uk-wales-…
At the terminal

Wear your N95 (notice a pattern). The higher risk times are check-in/baggage, security and customs, where you will be close to people for extended periods. Try to go through this as fast as possible and distance from others.

4/13
At the gate, try to find empty space away from people. It's large, open and usually well ventilated, so overall low risk.

Boarding

This will be the highest risk time. Once you are on the plane you will be hot-boxed and you can't prevent it.

5/13
Ways to minimize risk:
1. Wear a N95 (no kidding)
2. Minimize time - be the last to board if possible. You might lose luggage room in the overhead bin. Prepare accordingly.
3. Eye protection - if there was ever at time to use eye protection, this would be it.

6/13
Sealed swimming goggles provide sufficient protection. If you think it makes you look silly, then wear a bathing suit and tell people you are going to the beach.
4. Personal HEPA filter - keep it blowing on your face (might help)

7/13
Airplane Ventilation

Air will flow from the nozzles above your head and exhaust by your feet. It provides clean air, either outdoor air or recirculated air filtered through HEPA.

(Thank you @CPita3 for explaining this)
8/13
Airlines can run the air conditioning system in different ways:
1. Only when the engine turns on at taxi. Not on the ground.
2. On the ground with the auxiliary power unit (APU)
3. On the ground with a ground cart.
4. On the ground in recirculation mode.

9/13
Recirc mode is only filtration and lower flow.

They should always have it running, but don't. Once it's operating at full speed, risk is much lower. You can remove your goggles and turn off the personal HEPA (if you have them). Make sure the air is pointed at your face.

10/13
The main risk will be infected people next to you breathing on you. Otherwise, it's a pretty low risk environment.

People often refer to how flying is safe. It's because of the good ventilation/filtration in-flight. They are ignoring being hot-boxed at the gate.

11/13
Getting off is a similar story, once air from the nozzle stops, there's no ventilation or filtration, so it's high risk again.

If you can, throughout this whole process, wear a N95, try to move as quickly as possible and distance. Time is a risk factor, so minimize it.

12/13
If you are staying at hotels, just follow this thread. Enjoy your vacation.

13/13
Other Resources:
APU = Auxiliary Power Unit - what can provide ventilation (bleed air) when the engine is off
ACS = Air Conditioning System

ECS = Environment Control System - this includes the air conditioning system (ACS) and the bleed system which takes air from the engine or APU (auxiliary power unit) and supplies it to the ACS.

I always get asked what personal HEPA I use. I don't like endorsing products, but I use this.

canadiantire.ca/en/pdp/noma-pe…

Find a power bank to power it.

• • •

Missing some Tweet in this thread? You can try to force a refresh
　

Keep Current with Joey Fox

Joey Fox Profile picture

Stay in touch and get notified when new unrolls are available from this author!

Read all threads

This Thread may be Removed Anytime!

PDF

Twitter may remove this content at anytime! Save it as PDF for later use!

Try unrolling a thread yourself!

how to unroll video
  1. Follow @ThreadReaderApp to mention us!

  2. From a Twitter thread mention us with a keyword "unroll"
@threadreaderapp unroll

Practice here first or read more on our help page!

More from @joeyfox85

Joey Fox Profile picture
Dec 14, 2023
The @NukitToBeSure Tempest

I was shipped this PC fan box and put it together. It looks really good. I think for many situations, this is the best option out there. Here are some thoughts about it.
1/11 Picture of the Tempest PC fan box.
I stated earlier on my blog: we need a PC fan air cleaner that is durable and looks good. While durability and looks are not the most important aspects of air cleaners, many companies want that. We now have it.
2/11 If a commercialized cleaner using PC fans similar to the aluminum fabricated PC fan CR box existed, it would provide an ideal solution for commercial spaces.
It took me about 1.5 hours to put together. It was a little more difficult than the @cleanairkits ones because Clean Air Kits uses plugs to snap the fans on instead of screws. This could be something adjusted in the future. 3/11 Image
Read 11 tweets
Joey Fox Profile picture
Oct 18, 2023
The blood libel is a deep scar from Jewish history. Jews were accused of slaughtering Christian children and baking their blood into the matzah we eat on Passover. It lead to pogroms against Jewish communities where many Jews were massacred.
We just witnessed a new blood libel created over the past day. Unverified claims by Hamas were promoted by MSF, the UN, politicians and many major media outlets.

We've seen the resurrection of all the classical antisemitism: pogroms, massacres, blood libels, death squads
This is a description of the Khmelnytsky massacres in Ukraine 1648–1649.

Nothing has changed. Rav Hanover describes the cruelty in great detail. He mentions the terrible killings which occurred in the towns of Pereyaslaw, Baryszowka, Piratyn, Boryspole, Lubin and Lachowce: These persons died cruel and bitter deaths. Some were skinned alive and their flesh was thrown to the dogs; some had their hands and limbs chopped off, and their bodies thrown on the highway only to be trampled by wagons and crushed by horses; some had wounds inflicted upon them and were thrown on the street to die a slow death… They slashed the bellies of pregnant women, removed their infants and tossed them in...
Read 4 tweets
Joey Fox Profile picture
Sep 20, 2023
I've updated my post on Intro to Far-UV.

Since I first published this post, there have been multiple experiments showing ozone is a concern when using far-UV and needs to be taken into consideration.

itsairborne.com/intro-to-far-u…
In the post, I discuss how initially we didn't think it was a concern. I think ASHRAE needs to update their guidance on different UV wavelengths. ozone section in the blog post
I have far-UV in my house. I think for personal residential use, it can be used in a limited way if you understand the risks with ozone and mitigate it with open windows when in use. That's how I use it. Image
Read 5 tweets
Joey Fox Profile picture
Jul 6, 2023
ASHRAE 241 Equivalent Clean Airflow Rates

Here are the equivalent clean airflow rates from the recent ASHRAE Standard 241 Control of Infectious Aerosols. I've calculated the equivalent air changes per hour and the equivalent CO2 (if all the clean air was outdoor air).
These rates are doubled when there is "vocalization above a conversational level" (e.g. singing)

I'll be hosting a space with the chair of the committee @WBahnfleth to discuss these rates and more. Please join and message for any questions you have.
twitter.com/i/spaces/1gqGv…
To determine the ACH and CO2, I had to make assumptions about density and metabolic rate. I used values from ASHRAE standard 62.1 or found the closest approximation. If densities are different, the equivalent ACH would be different. It doesn't affect flow/person or CO2.
Read 4 tweets
Joey Fox Profile picture
Jul 6, 2023
What should you ask about your indoor air quality?

There are things individuals can do to improve the IAQ in their own space, but it ultimately falls on the building owners and operators to provide clean air. Here are some things you should ask to know about the IAQ.

1/10
1. Outdoor Airflow (OA)
- Is the system constant volume or variable volume?
- If it is constant volume, what is the airflow to the room (in cubic feet per minute [CFM] or liters per second [lps])
- if it's variable volume, what is the max and min airflow?

2/10
- what is the minimum OA % supplied during occupied hours?
- what is the occupancy schedule?
- is the system always running during occupied hours/auto mode?
- how often is it checked and maintained?

Learn about ventilation systems.

3/10itsairborne.com/intro-to-venti…
Read 10 tweets
Joey Fox Profile picture
Jun 27, 2023
"We need HEPA filtration, CO2 at 600 ppm and 100% outdoor air everywhere"

I see these types of comments non-stop. They are wrong and unhelpful. They show misguided ignorance about indoor air quality and what is actually required.
I'll start with filtration - you do not care about the filter efficiency. You care about the system effectiveness which is measured as a clean air delivery rate. MERV-13 with 300 cubic feet per minute (CFM) is identical to HEPA with 230 CFM. There's no reason to prefer HEPA.
Furthermore, air handling units can't handle HEPA filters. Demanding this is absurd when it will only increase cost and won't provide any benefit over MERV-13.

Having MERV-13 as the standard is sufficient for particulate matter issues.
Read 11 tweets

Did Thread Reader help you today?

Support us! We are indie developers!

This site is made by just two indie developers on a laptop doing marketing, support and development! Read more about the story.

Become a Premium Member ($3/month or $30/year) and get exclusive features!

Become Premium

Don't want to be a Premium member but still want to support us?

Make a small donation by buying us coffee ($5) or help with server cost ($10)

Donate via Paypal

Or Donate anonymously using crypto!

Ethereum

0xfe58350B80634f60Fa6Dc149a72b4DFbc17D341E copy

Bitcoin

3ATGMxNzCUFzxpMCHL5sWSt4DVtS8UqXpi copy

Thank you for your support!

Follow Us!

Send Email!

:(