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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.
$2.99 about. Pretty cheap and effective.
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
http://www.radioshack.com/Content/Environizer.asp
Suprisingly, for a radioshack product, they really work, and are a lot cheaper and easier to clean than "The sharper image's" ionic breeze thing...
The $199 one should do a medium sized computer room.
My opinion may be nullified by the fact that I work for RS, but I speak now of my own free will.
Sponge!
Since a large portion of the dust that we encounter comes from dead skin cells that are shed from our bodies, a clear solution presents itself:
Convice some of those dirty bastards using your lab to wash once in a while.
Need for air filter: GONE.
In a computer lab, I'm more concerned about the general flatulence and B.O. generated by most computer science majors. On a hot summer day, the smell can peel paint from the walls.
Scissors only cost a buck at Wal-Mart... Or you could go the more expensive electric haircutter route for about $15. Or, you could actually save money by getting rid of the cats.
I'm the Devil the Windows users warned you about.
One or more 20x20 furnace filters, and a box window fan. Some duct tape, or bungee cords.
Should be about $25 at your local mart, in the spring and summer. Hard to find the fans in the winter.
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!
Get a HEPA filter with a washable dust prefilter. Walmart sells several and you can get them rated for 20X20 foot rooms for $200, if your room is bigger then get two and set aside whatever is left over for replacement filters. Plus if your environment is that bad you should be cleaning the area for the workers sake, equipment is cheap to replace, sick or disgusted workers are not.
There are 4 boxes to use in the defense of liberty: soap, ballot, jury, ammo. Use in that order. Starting now.
I've had to deal with dust accumulating inside my athlon box, occasionally cloging up the GPU fan.
Here's what you do: "filter" all the intake holes in the side/back of your computer cases with paper towel sheets cut to size (Bounty works great for me, but dust can sometimes be a Brawny mess), both inside and outside wherever feasible. Air still flows through, but less dust comes inside. Haven't noticed an increase in operating temperature.
$cat
will spring for a french maid with a short miniskirt, high heels.
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.
HEPA filters are great for removing very small particles (like pollen) but they don't do anything for larger crudites. Hair and other dust settles so quickly that a HEPA wont get it unless the wind speed in your room is over 40 mph. And most HEPAs are rather noisy. For cat hair, a simple fiberglass filter near the computer will work fine. And a vacuum cleaner.
Your HVAC system will continue to supply plenty of fresh dust, so without a large filtering system, it's hard to have much of an effect on it.
I had a similar problem with a dusty store basement, and the solution was (please don't laugh) a chrome air cleaner (sized for a Holley 750 double pumper) attached to the blower fan. The automotive air filter was really cheap, replaceable, and quite effective. They have a big enough surface area that you have very little flow restriction. We did end up using a larger-diameter fan, which had a side benefit of making the server quieter.
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.
Anyone with cats knows the feeling.
Yeah, can anyone suggest a cheap filter to remove cats?
At $499 it is just barely in your price range, but it is one of the top-rated small air cleaners. It is electrostatic like the Sharper Image model, but includes a large fan to move air over the plates, making in much more effective for a lab environment. I believe that it is rated for an area of up to roughly 500 square feet. You can just throw the electrostatic plates in the dishwasher once every couple of months, and you really don't need to replace the charcoal filters unless you are trying to remove odors. I have been using one for 6 months and am very happy with it. The downside is that it is very ugly-- looks like medium-sized pet carrier.
This may sound a bit odd, but I've done it on a few computers (where the case permits) with abnormally good results.
Take a coffe filter, cut to size, and tape it infront of/behind all the air inlets to your case. Even after a year of sitting on carpet in a dusty area, the interrior was devoid of fuzz and dust pup^H^H^H bunnies.
Now, the last time I did this was in the pentium 133 area... Be sure to monitor processor temperatures for a few days to make sure you are getting adequate cooling.
Karma: SELECT `karma` FROM `users` WHERE `userid`=138474;
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.
You've stumbled across the solution yourself.
Obviously the dust is collecting in these machines. How do you 'remove' dust? You collect it.
So, all you have to do is build a bunch of redundant computers*, and design them with really bad air flow, so dust gets trapped everywhere in them. Once a month, open up these machines and turn them upside-down over a dustbin (outside). Voila.
*Imagine a Beowulf cluster.
Malike Bamiyi wanted my assistance.
I once watched a co-worker use a shop vac inside a very dusty PC. The shop vac sucked a chip out of its socket ....
-kgj
But back to the topic, how about building a plywood or MDF box for your computer, with weatherstriping on the door. Size it to take a standard furnace air filter (intake), and put a bathroom ceiling fan in it to blow the hot air out. Shouldn't be too hard to make, shouldn't cost too much, and you'll know when the filter needs changing just by looking at it.
Tip (and this applies to your furnace, too): Spray the filter with Endust. It'll pick up way more dust that way.
If all this should have a reason, we would be the last to know.
I've built plenty of rackmount systems with filters in place (cloth and wiremesh). It's a pretty common thing for servers and wonder why it hasn't caught on for workstations and home systems yet. I'm sure the cases are out there with the filtering on them, I jsut haven't had a look for any yet. If anyone is going to have them though, check out Lian Li, Procase, Saturn, Enlight, Inwin, or just do a general search. WHat you're probably looking for is something with a removable, reusable filter. DO a goole search and I'm sure you'll find what you're looking for on the cheap (ie. stay away from Lian Li for cheap). Otherwise, nice lil DIY project if you have some time, patience, and a spare case you don't mind butchering.
Cliff
sigs are like a box of chocolates, they all suck remove the underscores to email me
Yes, and its nothing but trouble.. ;)
The Doormat
If you're not outraged, then you're not paying attention.
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.
Consumer Reports is the best source of imformation about consumer level products around. They buy everything off the shelf so they don't get tweaked demo units, they do not accept advertising so they can remain unbiased, and they use repeatable scientific methods to test the products. Why would anyone not like them??? Just because you have had some kind of psychosematic aleviation of your symptoms does not mean that scientific principals are suddenly invalid.
There are 4 boxes to use in the defense of liberty: soap, ballot, jury, ammo. Use in that order. Starting now.
The way the ionic air purifiers work, you should move it *away* from the computer to get maximum effect. The way that you are doing it, when the device pulls dust back towards it, some (most?) of the dust will get diverted by the air flow of the fans. In fact, I would suspect that by putting the device *next* to the computer, you are actually increasing the dust flow to the computer.
An ionic air purifier has two parts. One sends out charged ions which collide with particles of dust and impart a charge to them. The other is an area on the unit itself that has the opposite type of charge. I've never used one, so I don't know how effective they are. However, given the way it works, it seems logical to me that the best place for it would be away from the computer. The desired effect of the device is to pull dust into its area. Instead, it might be better to have it so that it pulls dust away from the computer. Besides, I would think that throwing electric charges (which is the basis of the ionic effect) around near a computer would be undesireable.
Here is a link to purchase it: Friedrich C90A
Take the fans out of your computer, it wo
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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.
Make sure you use USED dryer sheets, or you'll find you're PC components covered in a weird film. Another plue is that it keeps your PC smelling fresh.
Just because you have had some kind of psychosematic..
if you're gonna use big words at least learn how to spell them.
If you mod me down the terrorists will have won
Sell the cats to a Chinese restaurant. End of problem.
Max
My god carries a hammer. Your god died nailed to a tree. Any questions?
We *do* work in a coal mine and we *are* aware of "miners lung", thanks very much :-)
:-)
Yes, we wear dust masks when outside collecting / grinding samples, and also have a 6 monthly respirable dust check, where we get to wear a minature version of what I've described above (battery air pump , cyclone, filter) around for a day to check on the amount of respirable dust we breathe in. Every 5 years you're required by law to have a chest x-ray to check for silicosis if you still work in the industry.
It's generally only particles below 10 microns that you have to worry about breathing in, as they're the ones that *never* come out again. Particles bigger than 10 micron get removed via mucus and cilia in your nose/airway/lungs without much hassle. Luckily, 10 micron particles and below generally don't stay suspended in the air too long, they drop out pretty quick.
And anyway, we try not to go outside the lab too much. (Ahhhh! the light! It burns, it burns!!)
You are in a twisty maze of processor lines, all alike.
There is a lot of hype here.
All this talk of ionic and HEPA air filters is missing the first question: where is the dust coming from? Maybe you can take steps to reduce the ingress of dust into the lab. Maybe you need to punihs people for leaving the lab room door open to the dirty outside air...
If it's a university computer lab in a realtively modern centrally-ventilated building, it might just be enough to have a positive-pressure airflow of filtered air to push the dust out of the room. You might be able to hang the charge to the Buildings & Ground's account.
As others have mentioned, you don't state the size or "enclosedness" of your lab, but some thoughts anyway:
1. Most (90%+) dust inside a home or office is generated by the shedding of human skin and hair or our clothing. Hence, most dust is generated within 5 feet of the fans sucking it in to the computer. In these environments you should have at least low density foam filters (think about the one on your hair dryer) on each intake fan. The case fans of your systems should be positively pressurizing the case so that all incoming air passes through a filter, not through any small openings.
2. Try to keep the intake fans on the computer cases as high off the ground and as open/exposed as possible. Ex: don't stick the fan in a corner under a desk, this is where air currents will deposit the most dust. In that same vein, your HVAC intakes should be on the ceiling, not near the floor. Moving them can be quite inexpensive.
3. Don't use ionizers. Ionizers are different than electrostatic filters. Ionizers are designed to change the balance of electrical charge in the ambient air (they spit out electrons). To me that's just a bad thing when highly sensitive electronic parts are about. The more out of balance the charges are, the more likely you are to experience static discharges, and we all know that kills computers.
4. For larger labs/offices I recommend an electrostatic filter that gets built in to the HVAC system. These things are highly effective at removing the lightest/smallest of dust particles. They are a bit expensive to install, and aren't the easiest things to clean, but they do a great job and you probably have a cleaning/maintenance crew. These devices do put out a small amount of ozone but this is usually not a problem with the normal air exchange that takes place in an average building. If you have a VERY high efficiency(tight) building, consider having an indoor/outdoor air/heat exchanger installed, or have the power in the filter unit reduced so ozone production is minimized(this is usually a jumper setting in the power supply). Most U.S. buildings will not require such measures.
5. Don't underestimate the effectiveness of a simple furnace filter at the air intake and/or exhaust points from your HVAC system. Paper is the best filter, but reduces flow the most. Foam filters are pretty good, especially the "charged" ones. The cheap "spider web" filters are useless, don't use them. They'll catch large debris, but not the stuff clogging up you case fans.
6. If this is a very small room, one or more portable HEPA filters will help immensely. I install these in all the smaller server rooms that I work in. Run them continuously(24x7).
7. If at all possible, have your cleaning crew use HEPA filters on all vacuum cleaners used in your lab. Otherwise, a significant amount of light dust will simply be blown out of the vacuum unit and in to the air where it can be sucked in to the computers. Even better than the HEPA filters is to use a built-in type vacuum system where exhaust air is routed outdoors.
In my home, I use central electrostatic filters, a central vacuum, and keep my computers on the desk, not the floor. I have VERY little dust accumulation in my systems (or anywhere else).
Article X: The powers not delegated... by the Constitution...are reserved...to the people
Actually, the article you mention suggests that they do a pretty good job - it is ozone generators that are recommended against. It does warn that "ozone generators, negative ion generators, and certain other electronic air cleaners that are not listed by the FDA, or cannot otherwise prove that their ozone emission levels are lower than 0.05 ppm, may produce levels of ozone recognized as unsafe for humans and are not recommended for use in occupied spaces because of the risk of generation of ozone"; however, that depends on the air cleaner and is probably much smaller with devices not intended to produce ozone. (Anyone know if there are any results from such tests? Consumer Reports, maybe?)
The Living air classic is great. We've tried many different heppa filters over the years and haven't been completely satisfied either because of the total cost of ownership or because of the noise.
A friend of mine had been raving about the Living Air Classic for a while so I decided to finally order one to see what the fuss was about. They range in price depending on the size of home you have but the one we have cost us around $400.00 and it can clear a 3,000 sq ft house in a few days. It's quite and doesn't need any maintence.
The site is www.livingairclassic.com
After living in Lubbock, Texas for six years and dealing with the effects of huge volumes of blowing dust in my computers, I finally discovered a solution to all of my dust problems.
I moved to Austin.
Peter
Downsize DC Today!
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.
I was thinking... you could blow air into the bottom of a barrel of water, let it bubble up to the top and put it back into the room. I know from a really reliable source that water bongs get much of the nasty stuff out of pot and make the smoke much smoother. Of course I've never actually tried to clean the air in a room with one but it seems like it might work.
Can't you spell the word out? For Pete's sake, it's only 45 letters long:
pneumonoultramicroscopicsilicovolcanoconio
// file: mice.h
#include "frickin_lasers.h"
If you get too much ozone in your office, you could always release som CFCs, which readily break down O3 and make it harmless.
:) , but this can cause other problems, as chlorine is poisonous.
My understanding is that the CFCs themselves do not break down ozone.
What happens is that, in the upper atmosphere, sunlight breaks down the CFC, releasing, among other things, chlorine (the first "C" in CFC).
The freed chlorine is what breaks down the ozone.
In your room, the CFC is not going to break down (at least not in any measurable amount), and so will not break down the ozone.
OTOH, dumping Chlorox in a pan might have the desired effect
Those who sacrifice security to condemn liberty deserve to repeat history or something. - Benjamin Santayana
Cat pee is extremely corrosive. One spray sucked up by the system would probably ruin it. ( remember, the fan exhausts air, so any contaminant sprayed around the case is going to go IN. )
"Prove all things; hold fast that which is good." [KJV: I Thessalonians 5:21]
That link comes up a lot when people are asking about the Ionic Breeze and the like online. FWIW, I have four of them on 24/7 in my house to manage dust and allergens until I pony up the cash to put one in the HVAC system directly.
That article talks about air cleaners, not air filters. These are ozone generating machines you'd use if, for example, someone took an explosive dump in your car. It uses very high amounts of ozone to physically removed odors and clean the air in there.
Ionic Breeze's are electrostatic air filters, totally different beast. An electric potential between two ionizing wires in the back and three collector rods in the front pulls air through without any noise, and the dust picks up a static charge and sticks to the collector rods. Thats it. In terms of controlling dust, one big thing that Sharper Image doesn't mention, which may counterindicate their use in a computer lab, is that if your air is fairly dry, it puts a slight static charge on every damn thing in the room. Fantastic for controlling dust, because you can just vacuum it off the couch, but you're always zapping yourself.
Anyway, my point is, there's nothing in common between these filters and what ALA is talking about.
I am not really surprised how many people think that devices without fans or filters work. Wake up people. It is the same physics that make the ions stick to particles that proves that a volume of air is required to pass thru a filter if you want your air cleaned if at all. All scientific studies show that a filter (glass or carbon) must permit some pollutants to pass through in order to work. The larger the volume of air, the harder to filter, the more displacement needed (the bigger the room, the bigger the fan needed). If you have a small computer lab that you need to keep clean, a real hepa filter rated for the volume of air in your room will help. I have a small honeywell filter that was allergist recomended, I also have 4 severs and a workstation always running in my office. They collect dust no matter what. I dust gear once a month. Stay away from fanless devices. It is like filtering your room with a piece of cardboard (i dont know if anyone remembers the N.S.A. scandel that involved air filters) I have to agree with all the posts for cleaning and vacuming. That is where you start. Keep the enviornment and the gear clean first. Filter the air second. Clean again third.
One of the managers at a company ( which is no longer ) that I worked it looked at things like this.
I am an engineer. This is how I see it.
You lose a power supply. No big deal - but in the process of losing the power supply, you corrupt your system. Big deal. This could be very costly to recover from.
Now, even if you were lucky and the system suffered no damage from the failing power supply, you have the time to account for to take the system offline, obtain, and replace the supply. Time is expensive. You are now losing on two paths: You can not use the machine, and you are expending time finding parts and fixing the machine.
Personally, I find it much much more expedient to provide the infrastructure for trouble free operation than to let things fail and try to fix them. Yes, the power supply is cheap. So are engine bearings. But saving money by scrimping on oil changes is hardly a way to "keep companies running smoothly and profitably", rather, as an engineer, I see this the quickest way of running a company into the ground with soaring overhead maintenance costs.
Given my own knowledge of the costs involved and failure statistics, I would opt for prevention, but should the company see fit to make me subordinate to someone who sees fit to override my judgement, I would obey, but find somewhere else to work, for the higher-ups are apparently clueless about the mountain of maintainance costs heading their way - and have no idea how much the management skills they hired is really costing them.
I normally would not be so straighforward, truthful, and harsh in my reply, but you did post AC, so I feel you are fair game.
"Prove all things; hold fast that which is good." [KJV: I Thessalonians 5:21]
ULPA (Ultra-Low Penetrating Air) filters are 1 to 2 orders of magnitude more effecient than HEPA (High-Efficency Particulate Arresting) air filters; ULPA is rated to trap 99.999% of particles at 0.12 micron while HEPA filters only catch 99.99% at .3 microns. OF course, for most airborne dust and bacteria, the difference is negligible, since they're in the single-to-tens-of micron size ranges - but ULPA is clearly the superior choice, and not much more costly than HEPA at all. Incidentally, you might want to consider ULPA filters if you make IV infusions - a lot of viruses are small enough to only be trapped in ULPA filters IIRC.
Facts do not cease to exist because they are ignored. - Aldous Huxley
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
I once read somewhere about an insanely simple and cheap solution: cover the inlets and outlets with pieces of your (wife's / sister's/ grandmother's) tights stretched over the in/outlet between the fan and the perforation in the casing. I've experimented with this myself, and although it is quite cumbersome to actually get it done, and more cumbersome having to remove the cloth periodically to clean it (with water and soap), it does actually keep a lot of dust out.
JeR
I'd like to hijack this thread for my own needs.
I have a small basement room in our offices that I would like to turn into a server room. (10x12'). Unfortunatly it has no easy access to an external vent, and putting in the duct work would cost more than the computers it would contain.
Is there an (affordable) environmental control unit that can be used in a space like this or am I trying to find a loophole in the laws of thermodynamics?
-insert obligatory simpsons quote-
Would an evaporative solution work? I'm totally HVAC ignorant.
Water makes a *great* dust filter. The Rainbow line of vacuum
cleaners runs their output through a water pan, and the result
is a *lot* less dust (if you sweep at all regularly). Now, those
things run a fair penny more than the $500 you were looking at,
but you can probably take advantage of the same principle for
well under $500. You need two things: a system for rotating
the room's air so that any given bit of air makes it to your
filter system periodically, and a filter system that takes the
air and forces it down into a bucket of water. You do have to
change the water, but that's easier and much cheaper than changing
a traditional filter. (In theory you could rig something up to
automatically change the water, but probably not inside of your
$500 budget.) You can tell that stuff is being removed from the
air because the water turns black.
Cut that out, or I will ship you to Norilsk in a box.
Oreck (the vacuum cleaner people) sell an excellent air cleaner. I've had one for a little over a year and it is amazing what a difference it makes in my house.
The model I have has three filters; a reusable prefilter, a metal collector, and a carbon filter. The carbon filter needs to be replaced every few months (they are fairly cheap, $20-$30). The prefilter just gets rinsed off and the metal collector is cleaned every 4 or 5 weeks. Mine has a fan with 2 or 3 speed settings, at the "normal" speed it is quiet enough to not be noticiable.
I think there are a few new models, but they all operate similarly.
Matt
Look, guy, it's all well and good to believe unbiased reviews and so forth. I'm not saying that I'd consider CR a source of such, but hey, you believe what you want.
However, that's beside the damn point here. The guy has one. He says it works for him. To tell him he's been duped when he's the one cleaning the dust off the blades every couple of days is a bit ridiclous.
That's all people are saying. Nobody's defending a "shiny piece of crap", they're defending the guy who makes personal observations and decides for himself rather than simply believing anyone and everyone else's opinions.
As for "not moving air", you're wrong. You're just simply wrong. They do move air, just not as quickly as one with a fan. You can hold up a piece of silk ribbon in front of one of the things and see that for yourself quite easily. Or if you prefer, blow smoke at it. That works just as well. I admit that it doesn't move 6 roomfulls of air in an hour, but then that's the whole point. Some people need air filtering, but cannot deal with noise. If you need air filtering and don't mind noise, then by all means get a fan system.
- Give a man a fire and he's warm for a day, but set him on fire and he's warm for the rest of his life.
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.
Looking for freelance Actionscript (Flash/Flex) or ColdFusion work and/or freelance developers. Email me, put Slashdot
During Desert Shield/Storm, we airmen were faced with a similar problem. We also had no access to anything approaching a proper filtration system. However, we could get coffee filters since us zoomies can't be without coffee ('cept myself, the token tea drinker).
We taped the filters over the preferred intake and plugged up the rest of the vents.
Doubtless you may want something more elegant, but hey if it's an equipment room who cares.
--byterbit
"Nothing in the world can take the place of persistence. Talent will not. Nothing is more common than unsuccessful men w
I look after about 1200 computers in public schools. I suggest you make sure that the computers are up off the floor, the higher the better. Buying computers with decent quality fans also helps of coaurse.