CPAP machine practical in workshop for someone who's very sensitive to wood dust?

[Doug Hobkirk]

I ask simply because I am curious. The machine could be located wherever, like outside the shop or in a sealed box fed with outside air, and the hose could be however long. I trained myself to stop mouth breathing, so I am comfortable with lightweight headset. And I've become used to the tube.

296135
Very stylish, don't you agree?


I read of people who have tremendous difficulty with wood dust, especially some species (walnut?).

I personally am not organized enough to do it, I personally am not very sensitive, I personally DO use CPAP. My track saw table and sanding station are with ten feet of an outside window.

------------------
CPAP Testimonial

In my initial sleep test, I stopped breathing just over 60 times an hour. That doesn't seem plausible, or maybe even possible, to me.
With the machine, I stopped snoring, which was BAD, although I never heard it. Two college buds and I shared a motel room last winter. Both were wary of me, but trusted my promise that I didn't snore now. In the morning, they reported the only sound was a faint whoosh noise from the machine, which I had left atop the bed. The next night they wouldn't let me put the machine under the bed because they liked the sound!
I've used it for 6 years and only missed two nights. Less tossing and turning, more rested in the morning.

[Scott Brandstetter]

I have to say I think this Idea has merit. Especially if you add the mask that encloses the nose and mouth. You have me thinking now...wonder if they sell Cpap machines on ebay? I think hanging the system in the center of the shop with a flexible hose...who knows

[daniel lane]

It's an intriguing idea, but seems like it would be quite the bother to set up when you can just get a PAPR. Of course, those treat the air before supplying it to you, where the CPAP would provide fresh air at a slightly positive pressure. In that regard, I suppose it would be like a poor man's SCBA, swapping the cylinder for a long hose. Hmmm. <ponder>



daniel

[Paul Wunder]

A CPAP or BIPAP machine is not designed for protection against wood dust and frankly for the price of a good CPAP, which is available by prescription only (since it is a medical device) you can buy a top quality 3M powered respirator which is designed for this purpose.

BIPAPS and CPAPS have tiny 1"x 2" very thin filters designed only to prevent large particles of dust from entering the internal fan. The filters would quickly become overloaded within minutes in a shop environment. Also, the units are designed for a hose length of about 6' in length with an impeller strength to match. CPAPs and masks will cost about $1K and a BIPAP will be over $2K. Lastly, the typical mask will block your vision in various directions.....OK for sleeping, but very dangerous in a shop.

[Doug Hobkirk]

A CPAP or BIPAP machine is not designed for protection against wood dust and frankly for the price of a good CPAP, which is available by prescription only (since it is a medical device) you can buy a top quality 3M powered respirator which is designed for this purpose.

BIPAPS and CPAPS have tiny 1"x 2" very thin filters designed only to prevent large particles of dust from entering the internal fan. The filters would quickly become overloaded within minutes in a shop environment. Also, the units are designed for a hose length of about 6' in length with an impeller strength to match. CPAPs and masks will cost about $1K and a BIPAP will be over $2K. Lastly, the typical mask will block your vision in various directions.....OK for sleeping, but very dangerous in a shop.

Wow! I get it - you don't like the idea! Sheesh...

But your points are somewhat off base:


I suggested locating the machine outside the shop, or in a sealed box with outside air piped in. Filters clogging? In 6 years I've never changed a filter after the first few months when I was being nervous.
I yoked two hoses together many years ago for convenience. I prefer the hose goes downward (they have options for it to go up) below my elbows. Freedom to roll over, and 6' gets slightly tight. Twelve feet lets me go open the window!
I got a new machine a year ago (medical coverage demanded it). Whenever I get a new mask every year or two, although I think the coverage allows for a new one every six months, I save the old hoses, none of which show any deterioration. So even though I'm asking out of curiosity, I happen to be capable of rigging an 18' (or 24') system for no cost.
And I freely admit that I am very tolerant of imperfect sterility. Although I did ask my PCP (of 30+ years, a common sense doctor) if my casual attitude was reasonable. I would not consider that OK for my wife (new kidney) who takes many immune system suppression drugs.

And, just to throw another log on the fire, most CPAP machines also have a variable humidifier integrated into the system. I found it didn't seem to help much and keeping that clean was the only maintenance I ever needed to do. I haven't used it for several years, and I haven't had to do any maintenance other than the occasional new mask. But it might help someone who is highly sensitive, and cleaning out the container every few days isn't a big deal.

[Jerry Wright]

I have been a dedicated cpap user for15 years. I have used it camping as well as all over the world. There is a fundamental problem with using one in the shop which has nothing to do with filtration, mobility, or cost. The problem is airflow. Try taking a walk, then put it on. You will find inadequate airflow to support breathing at elevated rates of respiration. Remember that it operates on a set pressure, If you adjust it well over your prescribed sleep ptessure, then it might work , but watch out for your passage ways!

[Matt Meiser]

They make supplied air respirator equipment that's actually designed for the job.

[Doug Herzberg]

Doug, I've been on CPAP for nearly two decades and have two old machines sitting in a closet. For woodturning, I have a Trend Airshield Pro, which was very expensive, but does a pretty good job of providing breathable air while protecting me a little from projectiles coming off the lathe.

I've thought more than once about something like you propose if and when the Trend fails. Woodturners stand in one place for a long time, so the hose issues seem less consequential. CPAP machines are well built and seem to last forever. They can be purchased new online for $3-400, but you do need a prescription. I would think there are many pack rats like me who can't throw away a functioning machine, but might be persuaded to part with one for a small price.

A small enclosure to pre-filter the ambient air in the shop would be pretty simple, if moving the machine outside is impractical. My full face mask for the CPAP costs almost $200 by itself and I'm not taking it to the shop, but I think most devices designed for the shop could be adapted. Also, I can't wear eyeglasses while also wearing a CPAP mask, so it wouldn't work for me.

If I can put a system together using what I have, I'll have more money for woodworking tools.

[Dave Richards]

I think you ought to try it and see what you get but don't expect too much.

As someone who works on them as well as critical life support equipment such as ICU ventilators and anesthesia machines, I think you might find the idea isn't that great. CPAPs and BiPAPs are designed to to work in relatively clean environments such as bedrooms. They are designed to move fairly clean air such as that typically found in bedrooms. As mentioned before, the intake filter is only designed to keep out the big chunks, not airborne particulate matter such as wood dust. You can put the device into a box with filtration designed to filter out the dust but you'll need to provide some active method to get air into the enclosure. Otherwise the CPAP's blower will have to work harder to draw in air. That will affect the operation of the unit. Adding length to the hose will increase back pressure at the blower which also makes the blower work harder. It might be able to handle 12 feet of hose instead of six but coupled with the restriction on the intake from enclosing the unit in a box, you may find the unit overheats and the blower life reduced.

If you are putting two hoses together when you use the CPAP, did you have appropriate adjustments made to the settings? Pressure monitoring in the patient circuit is measured proximal to the machine to simplify the breathing circuit. If the unit settings are made for a six foot long hose and you add another six feet, you've changed the situation and the settings won't be right for you. You might not notice a difference but then again, you might.

[Doug Hobkirk]

I have been a dedicated cpap user for15 years. I have used it camping as well as all over the world. There is a fundamental problem with using one in the shop which has nothing to do with filtration, mobility, or cost. The problem is airflow. Try taking a walk, then put it on. You will find inadequate airflow to support breathing at elevated rates of respiration. Remember that it operates on a set pressure, If you adjust it well over your prescribed sleep ptessure, then it might work , but watch out for your passage ways!

That's an interesting idea, Jerry. I might try an experiment: 15 minutes using dumbbells wearing the mask - that's 15 more minutes that I've done in the last year! I've never adjusted the pressure, that might bear non-sleeping experimentation.

[Doug Hobkirk]

Doug, I've been on CPAP for nearly two decades and have two old machines sitting in a closet. For woodturning, I have a Trend Airshield Pro, which was very expensive, but does a pretty good job of providing breathable air while protecting me a little from projectiles coming off the lathe.

I've thought more than once about something like you propose if and when the Trend fails. Woodturners stand in one place for a long time, so the hose issues seem less consequential. CPAP machines are well built and seem to last forever. They can be purchased new online for $3-400, but you do need a prescription. I would think there are many pack rats like me who can't throw away a functioning machine, but might be persuaded to part with one for a small price.

A small enclosure to pre-filter the ambient air in the shop would be pretty simple, if moving the machine outside is impractical. My full face mask for the CPAP costs almost $200 by itself and I'm not taking it to the shop, but I think most devices designed for the shop could be adapted. Also, I can't wear eyeglasses while also wearing a CPAP mask, so it wouldn't work for me.

If I can put a system together using what I have, I'll have more money for woodworking tools.

I think the Trend shield looks very impressive. The stimulus for my idea was the idea of using pressurized outside air. (And not spending $300 (or whatever).

I have found zero used CPAP machines on eBay, current or past sales. I wonder why?

I had lots of difficulty adjusting to a full mask and then a half mask. At an expert's suggestion, I taught myself to breathe through my nose by taping my lips. It worked. Now I only need "nasal pillows." They lose the seal occasionally, but are easy to reposition. And now I can wear glasses - how can a person go to bed and not have the option of reading?

[Kerry Wright]

Doug, I'm right there with you except I stopped breathing about 54 times an hour. Wow, talk about a life changer.

I believe your idea may be plausible, but only for more stationary tasks. I can't see being able to contend with the hose (and maintaining a good seal) and moving around the various machines. Besides, I'm pretty sure I couldn't use it at all in the shop. After two minutes I'd be sound asleep :p

If anyone is interested, I have an older CPAP in the closet. As long as you don't mind it occasionally turning itself on and/or increasing to full pressure whenever it sees fit, I'd be willing to part with it.

[Paul Wunder]

CPAPS and BIPAPS are life changers. I have been using one for about four years. I was told to use one starting about 10+ years ago. I tried back then, but I could not learn to breath with the device. I also have ancillary lung issues.

The good news is that the technology has changed dramatically (at least on the better units). I urge anyone with sleep difficulties to seek help because prolonged sleep apnea can cause severe elevated blood pressure and markedly increases the risk of stroke. These machines are now eminently usable....and bearable! I now wouldn't think of laying down to sleep each night without it.

I have a ResMed Series 9 BIPAP (about $2300..which Medicare paid for) and I would highly recommend it if that is what is needed.

[John Coloccia]

I use a fresh air hood from these guys for spraying lacquer.

http://www.turbineproducts.com/fresh-air-respirators.html

[Doug Hobkirk]

I use a fresh air hood from these guys for spraying lacquer.

http://www.turbineproducts.com/fresh-air-respirators.html

Wow! Isn't that cumbersome? Does it get hot inside?

But those are technology questions. The important question is do you have severe allergies? And then I realized it's for "spraying lacquer." I keep thinking that one of these days I will learn to read...

[John Coloccia]

Wow! Isn't that cumbersome? Does it get hot inside?


It continually pumps fresh air, so it actually stays pretty cool. I wear the hood so I don't have to shave. For working in the shop, I use a Trend, but if I had severe wood allergies, I would seriously consider something like this if more convenient solutions didn't exist. It would probably get a bit cumbersome, sure. Anything that tethers you is cumbersome. On the other hand, you'll breathe clean air. It's really not so bad as you might think.

Why not talk to your doctor and see what he thinks?

[Doug Herzberg]

Looks like Ken Rizza did what we're talking about and wrote an article: http://cdn.shopify.com/s/files/1/0388/0669/files/ken_rizza_wtw_dust_mask_article.pdf?113.

[Matt Meiser]

That's just plain bad advise in that article. I'm surprised it was published. There's no way that's coming even close to filtering the fine dust. But hey, he did seal the hose hole with some duct tape.

[Dave Richards]

That's just plain bad advise in that article. I'm surprised it was published. There's no way that's coming even close to filtering the fine dust. But hey, he did seal the hose hole with some duct tape.

Agreed. I'm glad I won't have to service his CPAP. If that's all the filtration he's using he might as well just set up a fan on the opposite side of his work and leave the face mask off.

Doug, since you're so intent on setting up your CPAP this way, you should quit talking about it and go do it. Keep a fire extinguisher handy for when the overheated power supply and blower motor ignite the dust you'll be sucking into it. If you're as sensitive to wood dust as you say, it doesn't make sense to be screwing around with trying to get something to do a job it isn't designed to do. I certainly think more of my lungs than that.

[Doug Herzberg]

Agreed. I'm glad I won't have to service his CPAP. If that's all the filtration he's using he might as well just set up a fan on the opposite side of his work and leave the face mask off.

Doug, since you're so intent on setting up your CPAP this way, you should quit talking about it and go do it. Keep a fire extinguisher handy for when the overheated power supply and blower motor ignite the dust you'll be sucking into it. If you're as sensitive to wood dust as you say, it doesn't make sense to be screwing around with trying to get something to do a job it isn't designed to do. I certainly think more of my lungs than that.

I know you're addressing the OP, but I think if you is he is worried about fines, you need to find a new hobby or spend the bucks for a real system and use it whenever you're in the shop. Neither my Trend, nor anything we're talking about here is going to remove every particle from the air supply, but both can drastically reduce what you inhale. For me, the Trend nearly eliminates the allergic reactions I have to some woods when I use it. If I can save $3-400 and improve my air quality, I'm not going to worry about burning up a used CPAP, which I would never consider having serviced. The quality of the build on the pre-filter will determine the load on the CPAP and the size of particulate which passes through the system. The OP was talking about using outside air if possible.

[Alan Lightstone]

This all assumes that you do all of your breathing through your nose, and none through your mouth, which is clearly not true. It's the same analogy why you can't deliver 100% oxygen through a simple face mask - your inspiratory flow rates are dramatically higher than the flow rate delivered by the device, and you freely inspire large quantities of air around the mask. Of course, if you taped your mouth shut, and set the CPAP machine to deliver high enough flow rates / pressures ...

In this case in your workshop, while the CPAP machine delivers air under positive pressure to your pharynx and trachea through your nose, your mouth is freely inhaling air under ambient pressure to your pharyx. There the two mix, and are inhaled into your trachea. Think of a positive pressure of 5 mm Hg of the CPAP machine being overwhelmed by the negative pressure of 35-40 mm Hg being sucked in through your mouth. Which is going to win if the mouth route isn't obstructed by soft tissues?

The CPAP machine is designed to deliver air under positive pressure to overcome obstructions to your breathing (typically soft tissue, tongue, etc...) when you are sleeping, and can't consciously overcome them. That's a very different situation than being awake and breathing "normally".

[Dave Richards]

I know he was talking about a pre-filter and outside air. He's (and it sounds like you, as well) evidently ignored what I wrote before. If the pre-filter is fine enough to trap airborne particles, it will reduce the amount of intake air for the blower. This will cause the blower to work harder than it was designed to. Then increase the length of the hose and blower current will have to be increased again due to the back pressure created.

If the OP is "very sensitive to wood dust", he should be concerned with the fine dust and he should be using equipment designed for the job.

It seems like a false economy to me. How much would it cost to replace the shop because it burned down when the CPAP goes up. The insurance company isn't likely to cover it when the fire department reports the fire was caused by a CPAP being used inappropriately. And then there's the potential health risks. How much are your lungs worth to you? Evidently not $3000.

Excellent points by Alan, too.

[daniel lane]

Dave, the OP is Doug and he wrote, "I personally am not very sensitive". I respectfully suggest that implies he's not as concerned about the fine dust as you have presumed. Also, since the "extra hose will cause the unit to overheat" argument has come up a couple of times, let's figure out how much of a risk there is.

Assuming a CPAP machine with a 1/2" ID hose, 60LPM (typical maximum flow rate), and 10cmH2O (typical pressure), and assuming the smooth bore plastic hose is actually as rough as schedule 40 steel pipe and the air temperature is 72ºF, then the pressure loss from adding 6 feet of hose to the machine is 0.0095psi, or 0.67 cmH2O - less than 7% of the machine-supplied pressure. Since 10cmH2O is typical, not machine maximum, it's fairly safe to assume that you can slightly up the pressure without overloading the machine. I would also note that 1/2" correlates to the "slim line" hoses (15mm OD, or 0.59") so it's a highly conservative calculation. A normal 22mm hose would probably have an ID of ~3/4", so pressure drop would be roughly half, given that it is inversely proportional to diameter squared. False economy or not, I think we've shown that the fire scenario isn't likely.

Alan, I thought the flow rate limitation applied just to nasal cannula, not face masks, as well. My understanding is that face masks can supply ~15lpm, where cannula are limited to ~6lpm, and typical resting breathing is ~10lpm. Of course, that makes me wonder about CPAP machines, since my research said typical flow rate was 60lpm... <ponder>


daniel

[Jim Matthews]

They make supplied air respirator equipment that's actually designed for the job.

+1 on this.

Having an overpressure ventilator force dust into your lungs sounds like a bad idea.
Even if the compressor is outside the room, it won't filter the air sufficiently.

http://www.sawmillcreek.org/showthread.php?203837-Mask-and-air-filtration-system-recommendations-for-a-woodworker-with-COPD

Those of us that work more by hand have less dust to manage.
Remember - the fine dust you can't see is what does the damage.

[Doug Hobkirk]

This all assumes that you do all of your breathing through your nose, and none through your mouth, which is clearly not true. It's the same analogy why you can't deliver 100% oxygen through a simple face mask - your inspiratory flow rates are dramatically higher than the flow rate delivered by the device, and you freely inspire large quantities of air around the mask. Of course, if you taped your mouth shut, and set the CPAP machine to deliver high enough flow rates / pressures ...

In this case in your workshop, while the CPAP machine delivers air under positive pressure to your pharynx and trachea through your nose, your mouth is freely inhaling air under ambient pressure to your pharyx. There the two mix, and are inhaled into your trachea. Think of a positive pressure of 5 mm Hg of the CPAP machine being overwhelmed by the negative pressure of 35-40 mm Hg being sucked in through your mouth. Which is going to win if the mouth route isn't obstructed by soft tissues?

The CPAP machine is designed to deliver air under positive pressure to overcome obstructions to your breathing (typically soft tissue, tongue, etc...) when you are sleeping, and can't consciously overcome them. That's a very different situation than being awake and breathing "normally".

For your info, the way I taught myself to stop mouth-breathing was by taping my mouth shut! This was suggested by the doctor who founded the sleep lab I was using, to the point of the best tape to use. If I breathe through my mouth now, I feel the difference and it wakes me up. I snore LOUDLY if I am breathing through my mouth, so I've get feedback from others.

I used to pretty much always breathe through my mouth. Now I do it sometimes, but it's not my regular mode. The best riders in the Tour de France will often not breathe through their mouth, especially when climbing intensely steep mountains, so they can psych the competition out - Hey, he's not even breathing hard!​

[Doug Hobkirk]

Doug and Daniel., thanks for you coming to my "defense." You are right, I did say and am not sensitive to fines (fortunately).

I've gone from posing a question I thought might trigger some interesting thoughts to figuring out how I deal with the insurance company after I burn my house down!

I don't think I should mention my idea to grow eucalyptus plants outside the shop window next to the CPAP machine so I could be inhaling their aroma!

[scott vroom]

Doug, maybe I'm missing something here but a 3M half mask with a P100 filter will filter at least 99.97% of airborne particles. Is that not enough?

[daniel lane]

Doug and Daniel., thanks for you coming to my "defense."

Doug,

You're welcome, but it wasn't meant to be a defense so much as a continuation of a civil "brainstorming" discussion. I think there have been some good points made both for and against your idea - and for the record I think it sounds neat but probably isn't worth the hassle/etc. when there are other, better options - but just as your idea can be debated, some of the proposed reasons against (or for) can also be debated. For example, I think it would be much nicer to plant rose bushes outside the shop window. :)


Doug, maybe I'm missing something here but a 3M half mask with a P100 filter will filter at least 99.97% of airborne particles. Is that not enough?

Scott, speaking for myself, I think that it certainly can be / should be. I use such a mask (silicone with replaceable inserts) and in the summer, I wind up with a face full of sweat under the mask. I think Doug's original hypothesis was that the CPAP could potentially keep dust away and in a more comfortable way than a mask, but of course, he was asking us all for our thoughts. Personally, I think it's a neat idea that I would never pursue, much like the solar pizza box idea I had when I was 14. (It keeps your pizza hot during a picnic!) Just doesn't seem like the payoff would be worth the effort. But that's my opinion.


daniel

[Doug Hobkirk]

Doug, maybe I'm missing something here but a 3M half mask with a P100 filter will filter at least 99.97% of airborne particles. Is that not enough?

Scott -

I posted my question "out of curiosity." Some people are literally killed by WW dust, there are lots and lots of equipment sold to alleviate the problem, etc. I personally run an exhaust fan and have the garage door open and don't think about it. I usually run my shop vac (outside) connected by about 15' of hose to my ROS when I sand. Just look at what some of the responders in this thread use!

I originally hoped my question and responses might be useful to someone and that maybe a CPAP might actually be helpful. At this point, I think the first is true and the second remains possible. I might experiment to see if exertion overtaxes the machine or too-long hoses cause problems.

So, a 3M mask is way more than "good enough" for me.

------- And I wouldn't have made this reply if I had read Daniel Lane's response - He said it better --------------

[Frank Drew]

Not yet mentioned, but tethering yourself to a hose (or any kind of line, really) that could get hung up on something could be particularly risky if you're using power equipment; imagine that you're cutting something on the table saw and someone else in the shop accidentally gets his feet snagged in your hose. No bueno.

Daniel, I think non-rebreathers can deliver 15 l/m but simple masks (no bag) perhaps not; I'd have to look it up to say for certain, though.

[Robert Delhommer Sr]

Sounds like that idea could have great possibilities. :)

[daniel lane]

Daniel, I think non-rebreathers can deliver 15 l/m but simple masks (no bag) perhaps not; I'd have to look it up to say for certain, though.

That may be where my recollection is off. I just had 15 in my head from prior experience.


daniel

[scott vroom]

I can't imagine walking around my shop wearing a mask attached to a 30 foot or whatever long hose. How would that work for you?

[daniel lane]

Ooo, ooo, check out the classifieds for a PAPR - someone buy it and then do the CPAP side-by-side for a comparison. ;)


daniel