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HEPA filter to keep neighbors second hand smoke out?
July 29, 2014 11:45 PM   Subscribe

My neighbor smokes at all hours of the day and night. We don't have an AC and have to have our windows open at night in the summers, with a fan pointed out one window, drawing his smoke in the other while we try to sleep. It bothers me and my wife a lot. Wakes us up coughing dry throat. He won't stop, we asked nicely. Are there any sort of filters we can use as a screen that will make any difference? I think it's cigars.
posted by brenton to Health & Fitness (15 answers total) 2 users marked this as a favorite
 
If you go that route you'll need to restrict / control the air flow rather than count on being able to dissipate it once it comes in. Ionizers and such are options for indoors but you need to make sure it doesn't produce ozone (they often come with some sort of ozone-preventer) or you'll have another respiratory irritant floating around.

Maybe there's a way to place an outdoor-rugged-enough fan outside to deflect some of the smoke, and if you explore filters you can try to fix one of those window-fan assemblies in somehow, wedging together some degree of sealing around the fans.

The most extreme airflow control would be a CPAP machine (sleep apnea) with a long hosed placed as far from the smoke as possible with its own strong filtration. That's totally extreme but it represents how far you can take the concept, and why it should be possible to simply legally / civilly shut down the smoking at night time if you're in such close proximity. Even if it's not possible, I mean, it should be.

I would also possibly explore a portable swamp cooler that resides in or outdoors, and the air it brings it runs through the wet swampy-cardboard stuff acting as a filter and humidifier for your lungs. Smoke might ruin the material quickly but I suspect with a continual water-trickle it would last quite awhile and do some amount of filtration.
posted by aydeejones at 12:22 AM on July 30


A good cheap relatively powerful fan system by the way where you can actually filter the air involves simply modifying a bathroom fan, using it in entirety to bring in air with a filter over the vent. You might rig one of those for your inbound air and then block off the rest of the window opening with plywood or foam or what have you -- you can actually get creative and make it relatively secure with window locks, dowels, blah.

It might be loud and annoying but not necessarily, there are good quiet models. Any "squirrel cage blower" like found in bathroom fan or in some swamp coolers is going to be able to handle sucking through a filter better than a typical bladed fan.
posted by aydeejones at 12:25 AM on July 30


Also I would try to bring the air in from the other window (with a filter over the intake) and out the window the smoke typically streams into (the most), trying to create an outward draft. If you have a little swamp cooler inside you can get away without an air-flow to some extent, just having one window cracked or opened somewhat and using the relatively cheap / efficient swamp cooler to control temperature, increase humidity for your lungs, and potentially filter some smoke.
posted by aydeejones at 12:30 AM on July 30


In conclusion, if I were faced with this problem and aesthetics weren't a major concern I'd probably try to rig a blower at each window, one sucking inbound, one blowing outbound, window sealed around each within reason to control airflow, filter on the inbound fan which is placed as far from the smoke as possible to minimize the amount of smoke simultaneously hitting the filter, the other one probably not filtered at all to maximize outbound air flow and pull harder on the intake / filter via air pressure. White noise source to overpower the fans if it's too much.

I so want to MacGuyver this
posted by aydeejones at 12:38 AM on July 30 [3 favorites]


where's the neighbour, below, across the way? if they're in the building, you could seal up sources of air in as many places as you can imagine smoke might be coming through (bathroom etc).

there are high grade commercial charcoal hepa filters that are used by cigar bars, you might search for those.

btw a smoker, i.e. addict, can't just stop on a dime. did you ask them to quit (vs smoke outside)? if so, it's sort of a massive ask (though i completely agree that smoking, indoors even, isn't a thing civil people are meant to do). however, i wonder if they might be amenable to a request that they put a filter in their apartment, as well. they might.
posted by cotton dress sock at 1:13 AM on July 30


I think (but don't really know, pls correct) the issue with a simple window-screen-like HEPA filter is that you need a good bit of force to push air through the micron-tight fiber... not ideal if you seek a cool night breeze kind of flow.

If you really want to go HEPA, you could consider using a 6" inline fan with a 6" inline filter. You can use a variable speed controller to adjust the speed of the fan. You may need to run the fan at a high-ish speed, depending on the size of the room. Figuring out how many CFM you need to run is easy. A 6" fan runs about 400-500 CFM at about 2 amps. Larger 8" fans may be quieter and move around 800 CFM. The filter needs to be rated for the flow of the fan you choose. You can get creative with insulation and how you mount the fan to keep it quiet - they get noisy at high speed. Try to duct with sheet galvanized duct, not the flexible accordion stuff, as it's far more efficient. Seal everything up except your air intake and an appropriately sized air outlet. (To make this kind of setup comfortable in a bedroom is beyond me. Maybe rig up an adjacent room and use box fans to keep air circulating?)

If you are in the same apartment building, I would consult with the management. Or, if at all possible, I would use several enormous fans to push smoke back toward this offensive neighbor.
posted by roygbv at 1:50 AM on July 30


Window fan.

And i'm thinking on a large scale here. Is this a house? do you have windows on more than one side?

You want to exhaust the side this neighbor smokes on, and intake the side where you get fresh air. You can run the fans at the absolute minimum speed, you just need the smallest amount of pressure to keep that smoke from every coming in.

It really takes only a very small amount of positive pressure out the window to stop this, if you can draw in from another window.

Your explanation makes it seem like you're already doing something like this and it's drawing it in. Do you only have windows coming in one side?
posted by emptythought at 3:04 AM on July 30


I have this issue now (and had it at my last apartment). It's obnoxious. What helped, sort of:

-If they smoke in interior or common areas, tape up any cracks. Also, any spaces between units (e.g. where pipes come up through the floor). Use common sense on flammable things and don't place flammable items near hot pipes, and don't obstruct fire exits, of course. But if they smoke indoors or in the hallways, you can cut down the infiltration into your apartment.

-Also if they smoke in common areas, tell your landlord; they probably don't want the building's smoke alarms going off.

-Try to suck air from the clean(er) side of the apartment (hopefully there is one), and exhaust it out the side where he smokes. I generally open two windows on the street side, and place a cheap box fan exhausting out the window to the parking lot, which is the area where people smoke most often. (Unfortunately, people still smoke on the street, just not as often, so this isn't a slam dunk even if you do have windows on two sides of the apartment.)

-Run a small air purifier ($30 at Walmart, replacement filters ~$10 and required roughly every three months) to cut down on overall particulate matter in your apartment, especially in your bedroom.

All of this helps. But honestly, what helps me the most is a small window AC unit. If that's an option for you, cost-wise and window-wise, I really, really recommend it. You can get a 6K BTU unit at Lowe's for $179 (might be less other places with sales), which is generally enough to cool most bedrooms, and the electricity cost is maybe $20 a month in the summer (I pay less than that and I'm running two ACs).
posted by pie ninja at 5:17 AM on July 30 [1 favorite]



there are high grade commercial charcoal hepa filters that are used by cigar bars, you might search for those.


Just a thought: Here in NC there are thousands of these just sitting around in restaurants since the smoking ban went into effect. Maybe there is a city or state nearer to you where you could make an offer on one?
posted by Mr. Yuck at 5:43 AM on July 30


Yeah I'm going to second the suggestion of a window AC unit if possible, since it's the simplest solution. They draw air from the room, cool it and then recirculate it back into the room, so smoke coming from outside shouldn't be a problem. In any case, there's a filter as well.
posted by katyggls at 5:51 AM on July 30


Okay, to clarify the situation a little. The room has two casement (tall, swing-out) windows. One of them perfectly fits two 20" box fans stacked on top of each other, pushing air out. It draws cool air in the other.

I was imagining a full-screen sized filter on the intake window, possibly assisted by two additional 20" box fans to help pull air in.

I was really trying to ask more about the filters than about the fan system, since I already have a fan system, but it sounds like people maybe are all taking the filter element for granted? I can't tell from all the contraptions people are suggesting what kind of filter you all have in mind. It sounds like most people think that a filter would indeed work to remove the smoke, but that it would require a lot of pressure. What kind of filter are you all thinking of? I threw HEPA out there in the title--are HEPA filters the best for removing smoke?

To answer a few other questions:

The neighbor walks around the alley outside our building when he smokes. Even when he's all the way down the alley, the smoke somehow travels up the alley (perhaps along the roof overhang) and into *both* our bedroom windows.

Our location on the second floor with only swing-out casement windows makes an AC or swamp cooler difficult to install. Landlord won't approve cutting a hole for a wall AC.
posted by brenton at 8:35 AM on July 30


In this video they simply place a HEPA filter (the kind you'd use for a furnace) in front of a box fan. The filter used is an Accumulair brand filter.
posted by carrioncomfort at 8:59 AM on July 30


In some places there are laws protecting apartment residents now...it looks like you might be in South Pasadena, not sure about that, but Pasadena has a non-smoking law for multi-unit buildings (including outdoor spaces...). Might be worth looking into.
posted by three_red_balloons at 9:48 AM on July 30 [2 favorites]


I would put multiple baking soda boxes in the window getting the most intake of smoke (the kind designed for sticking in your freezer to help with odors there). If that is insufficient, I would then revisit the problem. But that is where I would start.

(Yes, I have done this for similar issues, with good results.)
posted by Michele in California at 9:52 AM on July 30


Thanks for that video, based on that, plus this chart I found, a HEPA filter with MIRV of 13 should work. I think I'll just replace my screen with some filters taped in place, and maybe put another box fan in front to help draw air through.

Also, I was able to find the South Pasadena ordinances on smoking in multi-unit houses, and it looks like we should be able to force him to stay farther away.

Thanks guys!
posted by brenton at 10:52 AM on July 30 [1 favorite]


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