The recent article Get Extraction Smart prompted one or two readers to pose questions which I attempted to answer. In the next couple of blog posts I’m going to try and relate some of my own experiences in setting up a dust extraction system in my hobby workshop, where I don’t have to abide by COSHH regulations and the recommendations of the HSE.
Unfortunately, the whole sordid business of dust and dust collection is fraught with difficulty, requiring some considerable thought before investment in any equipment. There’s a lot of information about this extremely complex area out there on t’interweb, but unquestionably one of the best (if highly technical) sources is Bill Pentz from the USA.
Whilst it’s relatively easy to collect the larger visible particles of dust, it’s the tiny invisible stuff, much smaller than the diameter of a human hair, which may cause the woodworker long term damage and subsequent health problems.
One of the most common questions that Bill is asked goes along the following lines: “I’m proud of my heritage as both my father and grandfather were Appalachian woodworkers who handmade fine furniture. Neither ever used any dust collection, both mostly worked outside, and both lived until their early nineties. Why do you scare so many away from woodworking with your dust collection requirements, particularly worrying all about fine dust?”
I’m pleased his father and grandfather enjoyed their woodworking and lived to an old age, but they got lucky and managed to get good fine dust protection because they worked outside. When vented outside fine dust rapidly dissipates with no visible trace and breaks down quickly when it gets damp or wet. The damage from each exposure is so tiny that most never know they are building a problem, plus we have so much excess respiratory capacity that unless we have a bad allergic reaction, get poisoned or develop cancer, we never know of any problems as they occur. Although respiratory damage is rarely the cause of death, it can significantly worsen other age-related health problems that do kill us.
Reading further into Bill’s website, another very common topic is “How can I get good fine dust collection in my small shop without lots of expense?” The answer is simple, but not what most want to hear.
Bill’s response is as follows: “Unlike good fine dust collection, you can easily get good fine dust protection without much work or expense. A mask and good cross ventilation works and provides good protection. To protect yourself you need to wear a good properly fit dual cartridge filtered NIOSH approved respirator mask that goes on before you start making dust even if you don’t use power tools plus you need to run a strong fan in an open side door or window with your main door open so you have good cross flow ventilation. I use a 3M 7500 series respirator mask and a commercial 24″ fan blowing out a back door with my main (work)shop door open three to five inches. You can clean up with a broom and dust pan, leaf blower, compressed air line, shop vacuum, dust collector or cyclone, but our particle counters show the mask and fan need to stay on for about a half hour after you stop making dust and stirring the dust from your clean-up to get your shop air back to outside air quality. Then you can take your mask off and turn off the fan.”
There’s a couple of solutions in a nutshell, but they don’t sit comfortably with me or, I suspect, the vast majority of woodworkers who like to pursue their hobby on a freezing cold January day within the closed confines of a warm and toasty workshop. The thought of permanently wearing a close fitting face respirator all day leaves me joyless and if I had to, I’d probably give up and become a hermit.
Again taken from Bill’s website, he says “Government air quality testing shows that small shop workers including hobbyists who vent their dust collection systems inside consistently get more fine dust exposure in a few hours of woodworking than workers in large facilities that vent outside get in months of full time work.”
And therein lies the issue. It’s very easy to quote dooming and glooming passages from the website, but what can we as hobby woodworkers do about it?
As Bill mentions, one solution is to wear a decent face mask, then clean up the workshop with a soft bristled broom and wide mouthed dustpan, removing the mask after half an hour once the fine dust had settled.
Another option is to remove the fine dust hanging in the air by installing a filtration system, such as the one from Jet. I use a much older, single speed Axminster version (alas, no longer available) which does the same job as the Jet machine. I run mine from an electronic timer switched to come on and off automatically six times a day which keeps the ‘shop air reasonably clean.
Time and again Bill mentions venting dust collection systems inside and whilst my set-up is in no way perfect, I have found a way of venting it outside the ‘shop, which I’ll discuss next time, as well as explaining the features of my dust extraction system.