(reposting)
A lot of discussions has been going on around the role of 'healthy RH' to reduce airborne transmission, infectivity and severity of viruses and in particular COVID. A lot of the discussion assumes that RH is being maintained at current guideline levels (or greater) however after commissioning no reporting is required and anecdotally it seems that many facilities fall short. https://oem.bmj.com/content/oemed/early/2020/05/28/oemed-2020-106653.full.pdf . What is the current situation in California?
(from Walt Vernon)
There is a lot of fighting going on around this topic in the halls of ASHRAE. One question is whether or not it is going to be required (there is a movement to require 40%). A second issue is how to design systems for it, when we know people will turn them off. I have heard
(from Travis English)
I have data that I can share. I have about 20 ORs that are connected to our enterprise system, so i can do data analytics. Here's one facility (4 ORs)
80% of data: 36% +/- 13% , 36% +/- 15% , 37% +/- 14% , 39% +/- 13%
90% of data: 36% +/- 16%, 36% +/- 18% , 37% +/- 16% , 39% +/- 17%
I think what we should be moving towards are acceptable control ranges. There's no such as "perfect control to 40%". (First, we need to accept that.)
The "tightest" control I think I've seen is +/- 10% or 15%, for 80% of the data points (which means a 30% sway in RH).