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An Affordable Air Purifier For Dusty Computer Labs?
Alcimedes writes "Our lab has a serious issue with dust. I've had a number of power supplies stop working because of dust clogging up the fans, and it's getting annoying. So I'm looking into some kind of small (under $500) air filtration system, and was wondering if anyone else out there has already gone down this road. If so, what did you buy and would you buy it again? I'd prefer something where I don't have to keep buying filters, but that may just be a pipe dream." Anyone with cats knows the feeling. Can you suggest a reasonably priced answer to dust-borne failure?
despite the hype, the sharper image "ionic breeze" actually collects a lot of dust, and doesn't require replacement filters. I have one near my computer at my house, and it definitely collects a lot of dust.
The Ionic Breeze gets wonderful reviews. A friend of mine uses one in the house. I'm sure a few of them strategically placed could help your dust situation...no filters or bags to be replaced, so minimal upkeep. Link to follow: http://www.sharperimage.com/us/en/catalog/productv iew.jhtml?pid=175000&pcatid=1&catid=101
That's what you need. I work in a cleanroom making IV infusions and we have HEPA filters in the ceilings of the clean rooms. Of course we have HEPA filters else where as well, but it start with the room. That's the expensive option. The next best would be a Dyson vaccum cleaner with a HEPA filter to really suck up all the dust out of your lab.
"I just can't sit while people are saying nonsense in a meeting without saying it's nonsense" J Watson, Sci Am 288:(4)51
There are a few air purifier that might do the trick for not a lot of money. I'd say the few parts you should first look at is WHERE does the dust comes from.
If it's airborne, air purifier.
If it's more like cat hairs (like in my house) simply elevate your computer from the floor. 1ft high and you will get 1/8th the dust you used to have.
If it falls from everywhere, put your computer under something... and a good paint job can help too.
I know it's all common sense, but usually you can remove most of your problems with common sense.
Have a nice evening
Mike
The military's solution is called Preventive Maintenance (or PMs for short - yes, it's real). It basically boils down to wiping off the dust on a regular basis, just like you would with the rest of your house. It's not fun, but it works, and it's well under $500.
https://www.eff.org/https-everywhere
Clickable link here, sorry. :)
Sponge!
They're only about 6" deep with a front intake and top exhaust so you can push them right against the wall.
List prices in the $199 - $239 range. Check out appliances.com or even better, Froogle for retail pricing.
Also, see if you can talk to whoever in incharge of the heating/AC system in the building to see if there is anything they can do. Maybe Allergy Free has a filter that would work with the system or maybe you could get together the with the other groups of people in the building and buy an electrostatic air filtration system for the whole building. They work great on both dust and allergies. These are just wild ideas from brainstorming, they really aren't that realistic I guess. The first paragraph though will probably work well.
PS: We have electrostatic air filters installed in our house. We also had them installed in the house we had before this one. Our family has allergy problems and when we clean them, you'd be amazed the colors the water turns from what comes off them. They really do catch alot.
PPS: Or you could just watercool everything and run it all through one massive radiator. But this would be a bit more than $500. More pipedreaming.
Comment forecast: Bits of genius surrounded by a sea of mediocrity.
IIRC, Consumer Reports gave the Sharper Image Ionic Breeze a hefty thumbs-down.
You might look at air cleaners of the type used in woodworking shops... they'd be a bit louder than the Ionic Breeze (understatement), but they'd actually do something useful for the money spent.
Yes, the Environizer sold by Radio Shack(made by Honeywell) is a pretty good product. There are two huge differences between the two air purifiers sold by RS and Sharper Image: 1. The Honeywell Environizers have a silent fan built in; the SI product does not. Having a fan means you can clean a much larger volume of air. 2. Price. RS has much lower prices, at least $100 less than the competition for a comparable product.
I love my Environizer and recommend it to everyone who wants cleaner air.
A witty saying proves you are wittier than the next guy.
Don't know exactly how your computer room is set up, but here's what I did. There are two basic types of "filters" - mechanical and electrostatic. The mechanical filters work by trapping the dirt onto the filter. Throw away the filter, throw away the dirt. The electrostatic filters work by placing a charge on the dust particle. The particle is then attracted onto a nearby surface. This nearby surface may be part of the filter element (like with a permenantly-charged electret filter or a powered electrostatic filter), or it may get stuck to a nearby wall, ceiling, or piece of furniture. This is what happens with a lot of the "ionic" filters. The dust is out of the air, but it's not really removed from the environment. What I have on my central AC unit is a disposable pre-filter (like a conventional AC filter), a high-capacity HEPA filter (a cartridge that looks like a bunch of folded-up paper towels), and a powered electrostatic filter. I change the pre-filters monthly (they're cheap), change the HEPA filters once a year, and wash out the electrostatic element every 3-6 months. This keeps my computer and other electronics fairly clean, even with multiple cats. One way to tell is by the amount of stuff that gets attracted to the TV screen; not much. The only disadvantage to a powered electrostatic filter is the possibility of the creation of ozone.
Chaos maximizes locally around me.
I'm not sure on your lab setup, but if the dust is *outside* the lab, try a pressurising fan setup.
Get a 2 inch outlet cyclonic type air filter, typically used in tractors, bobcats and small motorised machinery.
Hook it to the suction of a blower fan, outside your lab.
Duct the exhaust of the blower *into* your lab.
Try and close as many doors and windows as possible.
The blower will pressurise your lab with clean air, which will try to escape out all the nooks and crannies in your lab, keeping the dust outside.
Don't forget to check the filter every couple of weeks until you get a handle on the maintenance interval required, and don't get a cyclonic filter too big for your fan, as they need high airflow to spin out the dust particles effectively.
This works for a coal lab of ours that is located very close to a 100,000t stockpile of loose,dusty coal. The dust is bad enough that if a blank piece of paper with a pen on it is left outside the "clean room" (still inside the building) you get a "shadow" of the pen on the paper in about 6-8 hours.
You are in a twisty maze of processor lines, all alike.
There is a lot of hype here.
Here is a link to purchase it: Friedrich C90A
After doing extensive research on the subject, and looking at tons of stuff that was available, I ended up plunking down $250 last November on a Sharper Image Ionic Breeze, the "Compact" Quadra version.
It hasnt completely reduced dust in our hosehold (we have unstained, un-sealed concrete floors, which are the #1 culprit, plus three cats), but its done an incredible job of keeping nicotine stains off everything in the computer room (my wife smokes). I put it next to her desk, and clean the "blades" every 3-4 days with a handi-wipe.
Definitely worth the money, but they're not the perfect solution for everyone. I'll probably be buying a refurbished full-size version from their online store or eBay soon (I dont see paying full retail price again).
Beware of stuff that is just negative ion/ozone generators - TOO MUCH ozone can be *really* bad for your health. The Ionic Breeze units put out a TINY amount (your laser printer, for example, probably puts out 10x as much), and the amount it puts out is well under federal health and safety standards.
HEPA filters were originally developed during World War II to prevent discharge of radioactive particles from nuclear reactor facility exhausts. They have since become a vital technology in industrial, medical, and military clean rooms and have grown in popularity for use in portable residential air cleaners. A true HEPA filter is defined as having a minimum particle removal efficiency of 99.97% for all particles of 0.3 micron diameter. The HEPA rating is determined using a test smoke with particles of 0.3 micron average diameter. To qualify as a "true" HEPA, the filter must allow no more than 3 particles out of 10,000 to penetrate the filtration media.
Negative ion generators force high-voltage electricity to one or more needlepoints. Electricity is simply electrons in motion and since electrons repel one another, when they reach the needlepoint, they jump off and attach themselves to the molecules in the air forming negative ions. At that point the allergens and other particles are attracted to grounded surfaces where they can get rid of that extra electron, causing them to settle on , floors, furniture and other grounded surfaces, even on your bed. It's important to remember that a simple negative ion generator doesn't capture or collect the particles in the air, it simply causes them to precipitate out of the air.
Electrostatic precipitators are used to scrub the air coming out of factories, but the same technology has grown in popularity in home ventilation systems and some room air cleaners. They are ionizers designed to charge and then collect particles from the air once they have been charged. First, the air is passed through an ionizer where the particles gain a particular charge. Then that air is passed between plates with the opposite charge that attract the charged particles. Electrostatic precipitators have one major drawback though; they rapidly loose effectiveness as dust builds up on the plates.
They Ionic Breeze is essentially an electrostatic precipitator with no real means of circulating the air past the ionizer and then past the charged plates making it essentially useless.
I run an Austin Air Cleaner in my computer room and it does an excellent job keeping it dust-free. The cool thing about it is that the filter needs to be changed only every 5 years and the pre-filter is vacuumable instead of replacable. I've found it to be a very cost effective cleaner compared to most HEPA-filter based air cleaners where you must change the pre-filters every three months and the HEPA filters every year.
Having a fan means you can clean a much larger volume of air.
MORE air yes, but it's not going to be nearly so clean. Longwinded explantion that goes into theory follows:
Ionic filters have a theoretical 100% efficiency for all particle sizes. How these ionic air filters work is an excercise left to the reader (apply - charge to incoming particles with a -1,000V grid, place a +1000V grid close by, all the ionized - charged particles stick to the + grid); there are scientific instruments to select a very specific size of dust particle that work on the same principle. Instead of two charged plates, they use a rod and sleeve electrode system with + in the center, and they have a very small exit slit at the bottom; the voltage across the rods is very carefully controlled along with the carrier gas flow rate (the dust has to be in some medium), and only one very specific size comes out the slit at the botton (+/- 1 nm). (TSI 3080 Electrostatic Classifier)
The theoretical equation for this instrument describes the arc taken between the two electrodes for a given size particle in a given carrier gas at a given flowrate and voltage difference. The carrier flowrate is absolutely critical, a few tenths of a percent deviation will throw your size off by a few *tens* of percent. Assuming these ionic filters are going for 100% efficiency, and they aren't running some insane delta-V like -5000/+15,000, they need a fairly low flow rate to allow all the particles time to drift over to the collector (small particles won't move very fast through dense air in a relatively low electrical field - c'mon people, i know it's early, but think about it - smoke diffuses, water droplets from a spray bottle drops from the air a lot faster) - so to make my point finally, the Ionic Breeze uses the electrostatic air flow, which is actually probably a lot better than a fan-driven filter. The fanned filters can clean more air, but they're going to leave a lot of the smaller crap untouched...I actually wouldn't be surprised if a HEPA filter was actually more effective than a cheap ionic filter.
Facts do not cease to exist because they are ignored. - Aldous Huxley
A short description on filters: There is, roughly, how many particles they catch of different sizes and how much air they attempt to filter. (Back to the ionic breeze later) In general, the latter is actually the dominant force in really helping you.
The HEPA standard is irrelevant (and no longer current) in any case where you might be standing in the unfiltered air. It's designed to keep radioisotopes from escaping laboratories. That doesn't mean HEPA filters are bad - but the HEPA standard is tremendous overkill in terms of what's important to you. A small HEPA filter, for instance, might have filtered 99.97% of very small particles out of 10% of the room air in the time another filter would have filtered out 80% of 90% of the air. (Math: about 10% vs. 72%)
That said, traditional furnace filters still suck :) as they barely do any filtering at all. In fact, I have a box of 20x25 for sale at http://www.xig.net/sale/ near Chicago. Filtrete is a wonderful solution that doesn't cost very much - and while the parent post mentioned this, I'm not sure they put enough emphasis on it. I ended up replacing my furnace fairly soon after moving here for other reasons, and I have a Honeywell F50 electronic filter on my furnace. It's not even a very efficient filter compared to HEPA, but it uses the gigantic fan that's on my furnance, so in the end, it's better.
There is a basic difference between electronic and physical media filters that _in general_ means electronic filters work better on smaller particles and media works better on big ones. The ideal solution typically is to put a large media filter in front of the electronic air filter - which is exactly what my F50 does. (There's a washable metal mesh filter) I believe this is the nature of the Ionic Breeze controversy - that it is ineffective on industrial debris in the air, but effective at pulling out allergen-sized particles. (Yes, allergens come in many sizes. But they're all pretty small. And, you're probably not allergic to dust mites, but to dust mite FECES - just in case you weren't sure it was tiny) I certainly think a fan might help it, but in my bedroom, for instance, it probably wouldn't matter because there's a ceiling fan and quite a bit of airflow (partially from ~ 12 case fans so it varies depending on exactly where...) My supposition is that it was designed with some sort of "average" room air circulation in mind.
If your goal involves making it easier for someone to breathe, make sure you catch those pretty small particles - Filtrete at least, electronic ideally. If you have allergies, there are lots of other things that help tremendously - like (now NOT just plastic!) covers on your mattress, hardwood floors, washing bedding in hot water... (Perhaps I'll turn this page into a webpage. Heh. I'm happy to answer questions, though, in the meantime. If I do, it'll appear at http://www.xig.net/allergy
Disclaimers and notes: I have a degree in Mechanical Engineering, I don't have an Ionic Breeze (they cost HOW much?), nor have I read the relevant Consumer Reports articles. I do think CR usually does great work, and I purchased my washer, dryer, and dishwasher from their reviews, but anyone can make a mistake. I do have pervasive airborne allergies, and have made a great many modifications to my surroundings to improve them.
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