HEPA air filtration

[Raymond Stanley]

Hi everybody.

I usually post in the neander section...this is my first post out of it.

I have seen the light on dust collection, even with the exclusive hand tool use that I participate in (nothing against power tools, just a personal choice for reasons I won't get into).

I have read about the question of the health benefits of air scrubbers/cleaners/filtration systems. I have also had great help from Bill Pentz.

If the woodworking air cleaners aren't sufficient for health benefits, what *can* be done to that fine dust out of the air (besides catching it at the source?).

Stuffing woodworking air cleaners with HEPA furnace filters? Homebrew solutions? Using home-brand HEPA air cleaners (honeywell, austin, etc.)? These are all solutions I've heard of. If we "know" that regular woodworking air cleaners don't provide health benefits, how can we know if these solutions would provide health benefits? Any insights?

Are the home-brand HEPA filters insufficient in terms of CFM? Does stuffing woodworking air cleanrs with HEPA filters mess with the "stock" filtration (if I stuff a hepa filter in, can I remove the inner filter?). Eek! So many considerations. Any comments would be appreciated. Thanks again to Bill Pentz for his incredible knowledge base that he has taken the time to share with everybody.

Thanks!
-Ray

[Peter Pedisich]

Ray,

Hi, I use a Festool C22 HEPA vac with all my power tools, a Rigid vac with 'Hepa type' filter for the planer/jointer/cms.
I also use two air filters; one I got from Lee Valley and a True HEPA filter by Honeywell to help clear the air from the Ridgid exhaust if I cannot route the exhaust outside.
In fact, I never use my tablesaw unless I can roll it out in the driveway. And I always leave the garage door open with large fan blowing out when the temp is above 50 deg.

My methods are obviously not ideal, but I am researching and saving up for a proper Cyclone. And I'm looking for a good mask that I can wear with my glasses and safety goggles.

Good Luck,

Pete

p.s. - by the way, great question!

[Jim Bell]

Save yourself a lot of time and money. Buy a cyclone. Mine is a Clearvue that keeps my a/c'd shop pretty much dust free.

[Art Mann]

I think your biggest problem is you have been spending too much time reading Bill Pentz's website. If you are a handtool user, then you are not going to be producing any hazardous dust anyway. If you are afraid of sanding dust, then it seems to me to be a lot more practical to wear a respirator than try to put in an elaborate dust collection system.

Just keep this in mind. The opinions of Bill Pentz are just that. He is not a professional in the field. My opinion is that because of his personal health problems, he exagerates the risks of wood dust to others. If you start digging in to the health risk information he states as fact on his website, you will find that it is either just opinion, or the studies he references are carefully chosen to ignore other equally credible studies that contradict his claims.

If you want to know dust collection methods and equipment, Bill's site is as good as any and better than most. However, if you are trying to find out about personal health risks, his authoritative comments are really just personal opinions.

If you really buy into the health risks of wood dust that Bill preaches, then my advice to you is to stop woodworking.

[Jim Becker]

My latest post to your question in the Neander Forum:
-------
Ray, a hand plane really shouldn't be creating and "dust", per se...and collecting at the source for a hand saw is going to be darn hard to do.

Sanding is the real issue at play here and there are any number of ways to help with that, including a downdraft table or an air filtration system positioned right at the bench that sweeps the fines from sanding away from you with enough air flow. Wearing a powered face shield when sanding can also help if you really want to get into such gear. (I wear one when sanding at the lathe)

A shop vac is not what you want. Shop vacs move a small amount of air at high pressure. "Dust collection" requires moving a large amount of air a low pressure...both from the standpoint of point-source pickup, such as with stationary power tools as well as for the down-draft or "back-draft" type setup I mentioned above. You can build either or both of the latter using a surplus HVAC fan system if you want to do so...

[Wilbur Pan]

If the woodworking air cleaners aren't sufficient for health benefits, what *can* be done to that fine dust out of the air (besides catching it at the source?).

What Bill has to say about the health risks of wood dust, dust collectors, ducting, and cyclones is accurate. However, Bill's own measurements have shown that even in shops where well designed dust collection systems are in place, that dust inevitably escapes into the air. Because of this, you need a back up plan to deal with that dust.

The best way is to open a window and exhaust the air to the outside. Obviously, this is not practical or possible for every shop. Living in a hot or cold environment wastes a lot of A/C or heat if you choose this method, and if you have a basement workshop like I do, there may not be an option for a venting system.

So that leaves air cleaners. The key is to get enough air cleaning capacity for your workshop. Conventional wisdom says that 6-10 air exchanges per hour is good. In my workshop I aimed for 25 air exchanges per hour, which should clear airborne dust very effectively: about 99.99% of the dust would be captured in 30 minutes. Unlike trying to upgrade your dust collection system, adding air cleaner capacity is easy -- just install another unit.

You can calculate the number of air exchanges per hour with this formula:

60 x CFM of air cleaner(s) / volume of workshop

And despite what Art says, there is considerable peer reviewed evidence to show that wood dust exposure is harmful to one's health. This is a fact. However, one does not need to stop woodworking to deal with this, any more than one would need to stop driving because of the risk of dying in an accident.

[Dick Sylvan]

Save yourself a lot of time and money. Buy a cyclone. Mine is a Clearvue that keeps my a/c'd shop pretty much dust free.

What type of a/c do you have? I am about to do that and am concerned about dust and the a/c unit. I also plan on getting a Clearvue.

[Henry Cavanaugh]

Hi, I use a Festool C22 HEPA vac with all my power tools

Peter iam considering a new vac to replace my noisy shop Vac. I use a DC for larger tools. I was going to buy a Fein for less money than Festool CT22. I believe the Festool Hepa is an upgrade. Have you noticed a difference between the two different filters. Iam still on the fence between Festool, Fein, Alto and would enjoy anyones imput. I will be using it for a new Domino and my preexisting Bosch sander

[Peter Pedisich]

Hi, I use a Festool C22 HEPA vac with all my power tools

Peter iam considering a new vac to replace my noisy shop Vac. I use a DC for larger tools. I was going to buy a Fein for less money than Festool CT22. I believe the Festool Hepa is an upgrade. Have you noticed a difference between the two different filters. Iam still on the fence between Festool, Fein, Alto and would enjoy anyones imput. I will be using it for a new Domino and my preexisting Bosch sander

Henry,

All CT22 dust extractors now ship with HEPA filters. I got mine before this and swapped out the 1 micron filters that were std and did not notice any difference in any respect. It's for peace of mind.
I agonized for months should I get the Fein or Festool or Porter Cable.
To get the bags and HEPA filters for the Fein raised the price significantly and still no variable speed or flat top to put the tool down (very convenient).
I like Ridgid SNR vacs for shop cleanup and Festool CT22 for dust extraction. Although if someone gave me a Fein I'd be VERY happy! They are awesome vacs - tha plastic they are made from is very tough, and they are the quietest vac I've ever heard.

Pete

[Art Mann]

What Bill has to say about the health risks of wood dust, dust collectors, ducting, and cyclones is accurate.

One thing Bill claims is that OSHA standards for an industrial woodworking environment, where workers are exposed for 8 or more hours a day, are not adequate for the hobby woodworker. Are you saying that is accurate? If so, what studies can you point to that lead you to believe this is true? The reason I ask is that Bill has published information on his website that is not substantiated by actual research. Most of it comes from the opinions of his own physician. The research he does reference is old and mainly from Europe and has been contradicted by at least one study done here in the US. I don't fault Bill for trying to do the woodworking community a service, but I think his own serious respiratory problems have clouded his reasoning and this is reflected and on his website.

[Jim Becker]

May I remind folks that the OP is concerned about dust collection in a primarily Neander environment. Let's not get off track discussing the merits of an online resource, etc.

Jim
SMC Moderator

[Art Mann]

Jim,

The only reason I bring up Bill Pentz and his website is that the original poster sited it as a major source of his information. That explains to me exactly why someone who only uses hand tools would worry about dust exposure. I am simply calling into question his basic source of information which I consider to be misleading and sometimes downright inaccurate. The point is that someone should always take a healthy skeptical look at the accuracy of the information he is reading.

[Raymond Stanley]

Thanks everybody for their contributions. I appreciate all the help, regardless of position. I agree that it is healthy to be skeptical, but the fact of the matter is I'm having lung-oriented reactions to wood in an exclusively hand tool environment. So I'm just going to operate on the assumption that there is dust that needs to be collected. I haven't had physical measurements of dust in the air hand tool woodworking - that would be the only sure-fire answer.
Saying that, I'd just like to move forward on getting people's experience with air filtering.

I picked up an Austin Air HEPA filter off craig's list, so I'm going to try that for a while. Hopefully it won't get plugged up too quick.

-Ray

[Wilbur Pan]

Raymond,

The HEPA filter you describe will help, but I too would be concerned as to how quickly it might get filled up, and whether it will circulate an adequate amount of air. I would keep it as close as possible to where you are working.

Despite the fact that Raymond is in a hand tool environment, sawing, whether by hand or by machine, still generates a lot of dust. Consider this: suppose I need to rip a board. I can do this in a number of ways: tablesaw, bandsaw, or by hand. In all cases, I'll have to make a cut along the same length of wood, which converts the wood in the kerf of the blade to dust. Regardless of which method of ripping I pick, more or less the same amount of wood is going to be converted to dust, with the only variable being the width of the kerf of the blade of the saw. Certainly a tablesaw has the potential to create more dust because the kerf of a tablesaw blade is typically wider, but a bandsaw blade and a handsaw blade have kerfs that are pretty close in width, which means that either method will generate similar levels of dust for the same cut.

One thing Bill claims is that OSHA standards for an industrial woodworking environment, where workers are exposed for 8 or more hours a day, are not adequate for the hobby woodworker. Are you saying that is accurate? If so, what studies can you point to that lead you to believe this is true? The reason I ask is that Bill has published information on his website that is not substantiated by actual research. Most of it comes from the opinions of his own physician.

Yes, I am saying that OSHA standards may not be adequate for an individual woodworker. In deference to Jim, instead of a lengthy post, here are some links that will answer your concerns.

I've already posted a link to peer reviewed studies showing the link between dust exposure and heath issues.

Why the concept of "safe levels" of dust is a red herring, and why any level of dust exposure may be hazardous to an individual wood worker.

Why OSHA standards may be a moot point, considering how much dust we generate in our shops.

And as far as the opinion of Bill Pentz's physician goes, I also happen to be a physician. A pediatric oncologist, to be specific.

Regardless of how Bill chooses to present information on his website, the fact remains that wood dust is a hazardous material, and can cause severe health problems at any level of exposure.

I am interested in the study you are talking about. Do you have a reference?

[Steve Sawyer]

Argue how you will, I think we can all agree that the less dust we breathe, and the less dust that gets on our shoes and clothes and carried around to the rest of the house and the family the better.

While hand tools do indeed produce significantly less fine dust than power tools, they still produce dust. Take a very well sharpened plane, use it for a few minutes, then look down inside the throat. What do you see? A coating of fine dust. Admittedly it isn't airborne until you take a bench brush and whisk away that dust, or put it up to your mouth and blow it away, but it's going to get airborne to some extent.

I have a DC fitted with a Wynn Environmental half-micron cartridge. Yet I noticed that when working in the shop for more than an hour or so, solely with hand tools, I would develop a dry cough from the airborne dust. Admittedly I was probably kicking up some dust that had escaped the DC and had settled on surfaces or floor, but it was something I needed to address.

I bought a small 450 CFM 1-micron air cleaner (a Jet AFS-500), installed a timer in the power cord and there was an IMMEDIATELY NOTICEABLE IMPROVEMENT. I run it on high speed when running any power tools, on low speed at all other times, and I leave it running for an hour on low after I leave the shop.

I know that I'm more comfortable, I'm probably reducing the negative health effects of breathing wood dust, and I know that my hobby isn't spewing fine dust all over the laundry in the adjacent area.

If you have an air cleaner, then putting high-efficiency filters that can remove very small particles - the smaller the better - is a good thing. If I find some that will do .5 microns for this air cleaner I'll put 'em on, but I know that I'm making a significant improvement by just filtering down to 1 micron. I'm not going to lose any sleep over it, but I'm doing what I can.