Entries from February 2010 ↓

Electronic Air Cleaners and Ozone

February 22nd, 2010 — Filter QA

When the topic of electronic air cleaners comes up it usually doesn’t take long for questions to arise about ozone and whether it is safe or not. So due to several comments on this blog and questions I have received by email I thought I would share a link to a report I found, published by the US Environmental Protection Agency. The report should provide answers to most questions concerning ozone and any health risks associated with it.

It is important to point out that the report mentioned below is only to illustrate the effects of over exposure to ozone and not to imply that electronic air cleaners generate that much ozone. The report refers to ozone generators, not electronic air cleaners.

The title of the document is “Ozone Generators that are Sold as Air Cleaners: An Assessment of Effectiveness and Health Consequences”

The topics covered are:

  • What is ozone?
  • How is ozone harmful?
  • Is there such a thing as good ozone and bad ozone?
  • Are ozone generators effective in controlling indoor air pollution?
  • If I follow manufacturers directions can I be harmed?
  • Why is it difficult to control ozone exposure with an ozone generator?
  • Can ozone be used in unoccupied spaces?
  • What other methods can be used to control indoor air pollution?

http://www.epa.gov/iaq/pdfs/ozone_generator.pdf

The table below is copied from the report for those who do not want to read the document.

Ozone Health Effects and Standards

Health Effects Risk Factors Health Standards
Potential risk of
experiencing:		 Factors expected to
increase risk and
severity of health
effects are:		 The Food and Drug Administration (FDA)
requires ozone output of indoor medical devices to
be no more than 0.05 ppm.
Decreases in lung
function		 Increase in ozone air
concentration		 The Occupational Safety and Health Administration (OSHA) requires that workers not be exposed to an average concentration of more than 0.10 ppm for 8 hours.
Aggravation of asthma Greater duration of
exposure for some health effects		 The National Institute of Occupational Safety and Health (NIOSH) recommends an upper limit of 0.10 ppm, not to be exceeded at any time.
Throat irritation and
cough		 Activities that raise the
breathing rate (e.g.,exercise)		 The Environmental Protection Agency (EPA)’s National Ambient Air Quality Standard for ozone is a maximum 8 hour average outdoor concentration
of 0.08 ppm.
Chest pain and shortness
of breath		 Certain pre-existing lung
diseases (e.g., asthma)
Inflammation of lung
tissue
Higher susceptibility to
respiratory infection		 ppm = parts per million

No Comments

Aprilaire Media Whole House Filter

February 2nd, 2010 — Filter QA

Question: I am considering replacing my Aprilaire media whole house filter with an electronic filter.  I will be replacing my heat pump within the next few months and would probably buy a Carrier electronic filter.  I am currently using the new upgraded 15 MERV April Air filter. My service technician recently told me that based on his experience, the media high efficiency media filters do a better job of keeping the inside of the air handler cleaner than the electronic filters and the media filters require far less maintenance. He recommended that I continue using the media filter and not replace it with an electronic filter. Your comments are very much appreciated.

I would agree with your service technician 100%. In my experience, electronic air cleaners are over rated. They may be  efficient at stopping smaller dust particles but are not as good at stopping
larger dust particles. For best results use media type filters such as Aprilaire and Nordic Pure.

No Comments