Comments on: Do UV Lamps Really Improve Indoor Air Quality?

By: Grant Vogel

Grant Vogel — Thu, 30 Dec 2021 16:55:35 +0000

I’m late to the party on this but that is an interesting question worth answering.

In the 2019 ASHRAE Handbook-HVAC Applications, Chapter 62 Ultraviolet Air and Surface Treatment it states the following:

“The dose is generally interpreted as that occurring on a single pass through the
device or system. Although the effect of repeated UV exposure on
microorganisms entrained in recirculated air may be cumulative, this effect has not been quantified, and it is conservative to neglect it.”

With that said, maybe there is new research on this topic. In all likelihood though, multipass efficiency is probably hard to model in the real world with so many factors at play.

By: Jeremy

Jeremy — Wed, 29 Dec 2021 16:55:54 +0000

In reply to abailes. I do have a major concern, I had one installed in may HVAC system about 2 years ago my entire family myself 42 my wife 37, my son 15 and daughter 7 have all been being diagnosed with multiple neuorlogical conditions any possible connections? Thanks Jeremy

By: gregory barrett

gregory barrett — Fri, 09 Apr 2021 13:33:38 +0000

what about LED UV lamps? Any problem with Ozone generation?

By: Kent Sjadwick

Kent Sjadwick — Sun, 20 Dec 2020 21:02:38 +0000

Thank you for the article.

As a homeowner with a White-Rogers electronic air cleaner installed in 1989 should it be shutoff and the two washable cells replaced with a 16 x 25 Merv13 filter? I wonder if the Merv13 will reduce the airflow too much. Does the White-Rogers generate excessive ozone if it’s properly maintained?

Thanks for your input.

By: Les Lazareck

Les Lazareck — Sun, 13 Dec 2020 23:43:30 +0000

For companies who would like to have the effectiveness of their UVC in-duct products tested, who do you recommend having them contact?

By: abailes

abailes — Fri, 20 Nov 2020 13:52:00 +0000

In reply to Sharon Eley.

Sharon, see the EPA’s page on

Sharon, see the EPA’s page on ozone:

https://www.epa.gov/indoor-air-quality-iaq/ozone-generators-are-sold-air-cleaners

Not only is ozone bad for health, but the evidence for its effectiveness at cleaning the air isn’t very strong. I would never have anything in my house that generates ozone.

By: Sharon Eley

Sharon Eley — Fri, 20 Nov 2020 13:41:16 +0000

In reply to abailes. I bought a UV light stand hat
I bought a UV light stand hat also emits ozone. I usually set it up in a room in my home fir an hour and leave the house for two hours. Then open doors when I get home to air it out. Is this dangerous for me? How much ozone can I breathe without harm to my lungs?

By: Scott D. Berkowitz, MD

Scott D. Berkowitz, MD — Sat, 31 Oct 2020 14:19:09 +0000

Dear Allison, Thank you for
Dear Allison, Thank you for your very clear and objective summary of this topic. I appreciate the time you took to develop this article, which is very helpful to the residential consumer.

By: Thomas D

Thomas D — Sat, 24 Oct 2020 15:53:43 +0000

Wow. It looks like someone
Wow. It looks like someone took a very long trip on the confirmation bias train. Allison, kudos for keeping a level head with your replies. The average person has never had this amount of information available to them in human history. It’s a damn shame so many people aren’t equipped to sift through it in a scientific way, even dismissing peer reviewed research and moving on until they find what they want to see. There’s a perfect meme I saw. It depicts Ralph Wiggum from the Simpsons sitting in front of a computer, typing “what I want to be true” into youtube and the caption reads “I’m a resurcher”.

Anyway, thank you for taking the time to write this blog and attempting to promote the best information available at the time.

By: Pete

Pete — Sat, 03 Oct 2020 07:08:13 +0000

I know your articles
I know your articles specifically talks focus mainly on in-duct UV treatment but with the current pandemic, what would be your recommendation for travelers who are looking for all options to disinfect hotel rooms?