Home Improvement → Indoor air quality and Air Purifiers

I have a technical seminar next month where my presentation topic would be Indoor air quality and air purifiers (I'm trying to design one ) .Since this forum has technical oriented users as compared to other forums I use I felt it would be a good platform to put forth few of the questions I have in mind .

Your inputs and experiences will be appreciated .

1)Would you buy an Air Purifier to improve indoor air quality in your home?
2) Do you know the difference between Ionic air purifier and standard HEPA type?
3) For existing users - What are the most important aspects for choosing a particular model/brand?
4) For existing users - Are there any problems that come along with using Air Purifiers or are there any functions missing that you would like to see?

Any comment or opinion is welcome .Thanks in advance.

I purchased 2 of these for work -

Dri-Eaz DefendAir HEPA 500 Air Purifier

Same equipment the pro's use.

Are you going to focus on small portable units or larger ones that are installed as part of the HVAC system? I don't think the general public as a whole know the difference between the two types you mentioned but anyone who is looked at them probably does to some degree. The people who are most likely to buy one for their home are people with allergies or some other condition of that type.

For us the most important aspects for choosing a unit are efficiency, time between maintenance (cleaning etc.) and of course overall cost. Probably in that order although they were all way quite heavily in the decision.

The feature that is either lacking or doesn't function very well in most units we seen or had is indication of when the unit needs cleaning and/or maintenance.

The only time I considered using one was last summer with the intense forest fire season we had.

Unfortunately, it wouldn't have done any good anyways as I had to keep the windows open (no A/C). Even if I would have purchased a portable A/C that would have been no good either as they bring lots of air in from outside either directly or indirectly.

1 - no, 2 - yes.
I find the regular cheap ($3-5 for a 3-pack on sale) filters for my HVAC doing a good job.

I think the source of low air quality is also important to know, Is it pollutants or lack of recovery air in a home.

I think ionic are the electronic ones though right? as in the same as electro-static.

Thanks a lot for your valuable input . I'm focusing on small portable units . Yes most of the consumers aren't aware of the difference between HEPA and Ionic . The Ionic purifiers release ozone and aren't as efficient as the HEPA filters but then they are priced much lower than the HEPA variants which make it the first choice for consumers. I would like to focus on cost effective HEPA portable units with decent filter life.

Instead of relying on fans to move air through filters, the ionic purifiers release a steady stream of negatively charged ions that electrify the bits of dust, dander etc. These airborne particles pick up the negative charge and become strongly attracted to positively charged collection plates inside the machine but in most cases, they become attracted to other charged surfaces such as walls, table tops and TV screens.To varying degrees, all ionic air purifiers release ozone, a potential pollutant.The truth is since ionic purifiers are fanless they can't collect airborne particles from more than a few feet away and even when small amounts of dust enter the device, the plates inside quickly lose much of their power to attract more particles. Meanwhile, the charged particles that stick to walls or TV screens don't leave the the room and can always billow up again to cause trouble.

I am one of those technical guys and designed several DIY air cleaners
over the years for each visit back home where they have truly horrible air pollution.

I have moved to a design which uses multiple automotive cabin air filters (titanium dioxide type) with separate computer fans in a custom enclosure. A cleaning/maintenance mode reverses air flow through all the filters while they are exposed to bright sunlight. That regenerates them ... with only solar power.

Answers to your specific questions:
1) Yes. I have helped many friends buy commercial systems.
2) Yes. I always suggest HEPA rather than Ionic.
3) Air flow, noise, power consumption.
4) Filter replacement cost for some models. Clogged filters reduce efficiency and increase noise on most models.

1) Yes, I have two, one in living room, one in a bedroom.
2) Yes, pretty much
3) noise, what is the smallest particle will it remove, how long does it take to replace the air in a room, reviews, I have one that has a couple different programmable timers, so it turns on and makes noise when I am not at home, cost of filters / how long do they last
4) the one in the bedroom is hard to open to check and/or clean the filter.

I think many users would pick a model that filters "X" amount of air with the least amount of fan/air noise, in other words a quiet running filter.

Think of a dishwasher: Most all of them will clean dishes, but I like one (and have one) that is quiet running.

The Claire unit looks really nice but please think about maximum 5W power consumption ... it is a TOY.

As I mentioned I wanted to know which outer casing design is good .

I just checked the rating of the Clair purifier after you got it to my notice but after going through the literature on their website looks like the filter they employ in these purifiers operate quite differently compared to the HEPA counterparts and does not require a large powerful fan to function efficiently which in turn brings down the power consumption »go-clair.com/blogs/news/ ··· urifiers .

Based on the feedback I received I'm planning to model my air purifier casing as a Blueair Clair hybrid .I think that should work fine .

You must agree that pollutants are captured/eliminated ONLY from the air which moves past their filter.

Suppose you design a magical 100% efficient air filter that does not restrict air flow but captures everything other than oxygen and nitrogen molecules.

Now calculate how long it will take to clean the air inside a completely enclosed 10x10x10 cubic feet room using a 10CFM fan compared to a 100CFM fan. It is NOT a trick question.

A 100 CFM air purifier which consumes a lot of power thanks to the powerful fan it requires , cannot be switched on 24/7 and generates a lot of noise versus a smaller model with a lesser CFM rating which can be operated 24/7 ,is virtually silent and consumes less power.The fact remains, an air purifier cannot clean the air if it is not turned on. Now which one would work fine as a room air purifier ?? The answer is obvious isn't it ?