@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.
If that is the case, your room is isolated from other rooms.
@JudahWorldChamp@kprather88@CorsIAQ@jljcolorado@HuffmanLabDU@Poppendieck 2- Supply outside air into the corridor and then this air seeps into the room. Two issues: 1) your corridor air might be contaminated with people in the corridor and 2) it can be a bigger problem if the pressure inside the hotel is not balanced.
📢📢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.
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
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
🧵 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?
I looked at many classrooms. Similar findings. Most do not have outside air and problems with exhaust fans of bathrooms (unless I am missing something - no reports it was fixed?).
Most schools have windows that can be open but windows are not a reliable method to get you a specific air change rate. For more information about ventilation:
COVID Safety Plan (1/2)
- People density was at 50% (by design)
- Other measures below.
Everything was followed properly, except social distancing.
Masks were enforced, even outside. One might ask how can you enforce masks if people are drunk? I saw 2 people holding a person to his room while a third person holding by two fingers his mask in place.. commitment!
There are three types of air cleaners:
- Subtractive: like filters, will remove the contaminant when it comes in contact with the media
- Additive: like ionizers, will emit ozone/radicals/ROS/etc.. to react with the air (will emit something to remove something)
- Hybrid
Filter media (MERV, HEPA), UVGI are proven because Standards/guidelines/>decade of testing exist to test efficiency and by-products.
NO Standard exist today to test additive/electronic air cleaners (none, nada, zero, nul, nula), therefore they are Unproven.