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
Marwa Zaatari Profile picture
@marwa_zaatari
Jan 18, 2021 • 5 tweets • 2 min read • Read on X
Which portable air cleaner do I need to buy ?
#SARSCoV2

Factors: mechanism of filtration, airflow + efficiency (CADR), purchase price, replacement cost + filter life, and noise. 1/5 🧵
Air Cleaner Selection:
- Start by the area of the room to be cleaned (y axis)
- Consider cost (x axis) and noise (look at color of the dot; <55 db at highest setting is probably a good level)
- Consider multiple air cleaners to keep noise level down.
2/5 🧵 Image
Choose only air cleaners that have mechanical filtration ( particulate filter media) with MERV 13 or higher or HEPA designation.
In graph above * means that there is an electronic piece to the filtration but it can be turned off. 3/5🧵
Be aware of false marketing:
HEPA-like
HEPA-style
99% HEPA
HEPAsilent
HEPA Ultra
Ionic HEPA
HEPAFast
HEPA Efficiency
HEPA Functions
HEPA Action
Plasma HEPA
Super HEPA
HyperHEPA

are ALL subpar versions of what constitutes a HEPA air filter.

Either HEPA or NOT HEPA. 4/5🧵
Stay away of fancy technology marketing:
Plasma wave
Fragrance Sponge
UV Light Sanitizer Eliminates
NCCO technology
Active oxygen generator
ionic purifier + composite catalyst
cold catalyst layer
negative ion generator
Bi-polar
PECO
PCO
Plasma
Cold Plasma
etc... 5/5🧵

• • •

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

Keep Current with Marwa Zaatari

Marwa Zaatari 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 @marwa_zaatari

Marwa Zaatari Profile picture
Nov 1, 2022
🧵A brave and courageous high-level sales executive at GPS (company suing me) provided explosive, truly extraordinary information detailing astoundingly poor conduct on behalf of the highest levels of GPS’s exec team.

🔥Details GFM page: gofund.me/94af426a

(1/7)
Examples of what the employee told me:

1) The results were fabricated for financial gain.

(2/7)
2) If we [GPS] sold the truth, we [GPS] would never have sold at the rate that we were selling, not at 20 times the rate we were experiencing.

(3/7)
Read 9 tweets
Marwa Zaatari Profile picture
Oct 29, 2021
Ventilation air,
Ventilation air,
Where are you?

🧵 Hotel and COVID-19 part 2.

You can find Part 1 here 👇 (still waiting for lab results - 1 more week).
@DavidElfstrom
This week, I stayed at an hotel and this time I came prepared.

Here are some observations about shared air, system type, filtration, and outside air rates.
Air conditioning system type = fan coil unit = fan + filter + cooling and heating coil.

➡️This system does not introduce any outside air. It only filter the air in the room by recirculating it through a filter then a coil then supplying back to the room. ImageImage
Read 11 tweets
Marwa Zaatari Profile picture
Oct 14, 2021
🧵The search for ventilation.
Hotel & COVID-19 Edition.

I stayed yesterday at brand name hotel. Here are some observations about shared air, outdoor air, and maintenance issues.
The room I stayed in does not have shared air. This is typical for hotel rooms. Air in your room gets recirculated and conditioned within your room only - by design.

Pic for unit in my room: window unit with fan and cooling/heating coil. Image
Indoor air gets recirculated on the side, conditioned and then blown from the top - as shown by my infrared camera. Blue = cold air. orange = "hot" air.
Hint: to know the intake of air on the unit, look where there is dust. Image
Read 12 tweets
Marwa Zaatari Profile picture
Sep 27, 2021
@JudahWorldChamp @kprather88 @CorsIAQ @jljcolorado @HuffmanLabDU @Poppendieck Hotels do not have shared air by design with 1 caveat.
- In your room, you will have a unit that circulates and conditions only your room air (not shared).
- This unit might be under a window, next to a window, or in corridor of your room next to the bathroom.

See pictures below
@JudahWorldChamp @kprather88 @CorsIAQ @jljcolorado @HuffmanLabDU @Poppendieck Typically, for outside air, hotels (like Hilton and Marriott) have an outside air unit on the roof that brings the air into the building.

So far so good.
Your room air is not shared air with other rooms.
@JudahWorldChamp @kprather88 @CorsIAQ @jljcolorado @HuffmanLabDU @Poppendieck There are two ways to get outside air to the room:
1- Supply outside air directly into the room. That is the preferred method. See picture below. You will see a diffuser above the ceiling, next to the bathroom.

If that is the case, your room is isolated from other rooms.
Read 6 tweets
Marwa Zaatari Profile picture
Sep 18, 2021
📢📢New! Air Cleaners Comparison:
1- Selection graph: 1.a. all + 1.b. only HEPA
2- Data download link
3- Request data link
4- Where to place air cleaner?
5- Calculate reqs
6- CADR and noise
7- Letter about unproven tech.

@CleanAirCrewOrg @DavidElfstrom
@kprather88
1a - Selection Graph - All (includes ionizers = unproven tech)
- X axis first cost + first year filter replacement cost in USD
- Y axis: Clean Air Delivery rate = volume of clean air in CFM (cubic feet per min) = ~efficiency x airflow Image
1b - Selection Graph - only includes HEPA
- X axis first cost + first year filter replacement cost in USD
- Y axis: Clean Air Delivery rate = volume of clean air in CFM (cubic feet per min) = ~efficiency x airflow

Fun Fact:
On average, for each 1 cfm of clean air you pay $1.8 Image
Read 12 tweets
Marwa Zaatari Profile picture
Aug 25, 2021
🧵 Answers to what the different strategies will result in term of air change rate

Example used throughout the thread:
👉Classroom: 960 ft2: 30' x 32’
👉Number of occupants: 30 (this is the design number, taking into account average classroom density).
Ventilation by code, this classroom should have 415 CFM airflow of outside air or 14 CFM/person.

👉This airflow is being forced through the HVAC system (unit in classroom or mechanical room).
When we check ventilation, the answer is not “yes” or “no”, the answer should be how much?
Read 9 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!

:(