Taking Wood Dust More Seriously (Long)
The unfortunate accidents Shelley and Matt experienced recently have certainly have gotten my attention about power tools. Not that I am using any of mine lately. Their accidents prompted me to post about the problems I have been having from exposure to wood dust in my shop over the past six months.
Before setting up my workshop about a year and a half ago I read everything I could find on working safety in a woodworking shop. This included Bill Pentz's excellent information on how to avoid the dangers of wood dust found on his website.
While I followed much of Bill's advice, I did not invest in a cyclone. My dust collection system seemed appropriate and used bags which filtered down to 1.0 micron. I could have been better about changing out of my shop clothes after working on a project. I always wore a disposable dust mask but usually took it off when I turned off a power tool. In hind sight, I should have done a better job of collecting wood dust at the source especially on my contractors saw and sanding center.
I was in very good health and at 50 years old was training for a marathon and riding my bike 30 to 40 miles a week. Also no breathing problems at all for the first year of woodworking. I was the last person I thought would have any problems with a reaction to wood dust.
After working on a project for about six hours last spring, I began to have some wheezing and shortness of breath. I took a break and walked out side and felt better. This had happened once before after several hours in the shop and resolved itself within a few minutes of stopping work. A few of days later I went back in the shop. The symptoms reappeared in about an hour and were worse this time. They barely got better when I stopped working.
By that afternoon I was breathing better but was really tired and having flu-like symptoms including fever and chills, an unproductive cough and what felt like burning in my throat and chest. I thought I was coming down with a virus made worse by being in the shop that day. I just could not believe (absent any prior history) working in the shop for such a short time could make me so sick so fast.
My wife (who is a physician) came home for dinner took one look at me and said "we are going to the emergency room". Six hours of tests, breathing treatments, IV steroids and other medications later we were on our way home with a diagnosis of bronchus and asthma. Three days later I was not any better and running a fever of 103. The bronchus turns into pneumonia with more tests and medications. It is two weeks before I can walk to the top of the stairs without stopping to rest and a month of medications and breathing treatments at home.
I take five months off and try woodworking again. This time with hand tools. I use the best respirator I can find and change my clothes and shower after being in the shop and limit my work to two hours at a time. No problems in the past month. The big lesson for me is taking the first incident of shortness of breath and wheezing more seriously. Given what I know now I would have significantly improved dust collection at the source on each power tool, used a real respirator and been more careful about wood dust in general.
Hope this helps anyone who is having any symptoms of allergies from working in the shop.
Lloyd Morris
Taking Dust More Seriously
I am curious. While completing purchase of an entire new shop, I left safety equipment to the very end. I puchased a 1200 cfm General DC unit with a 1 micron bag.
Today, I was compiling my personal safety equipment. Why is it that the face masks sold by Lee Valley, Highland Hardware and a few others don't list the micron screening size?
I'm thinking of getting a Tyvek suit, like those worn by spray painters, for the really dusty jobs. But I recall reading the Bill Pentz essay, and he said the .5 micron particles are the bad ones.
If I eliminate 1 micron at the DC unit, how do I filter down to 1/2 micron?
Gary Curtis:confused:
OK time for me to get on my pulpet.
I happen to work as a product manager for a safety house and spend a great deal of my time working with Industrial Hygenists selecting instrumentation to measure partiulate matter. any particles less the PM 10 (10 microns in size) can get into you lungs. an example of these typse of particles is asbestose which is between 6 and 8 microns. PM-1 (1 micron is so small that it can be absorbed into you blood.
Like many have stated there is no better solution then elimatring the source of partiulate. The problem as I see it is even the best cyclones don't always get the airborn stuff out of the air. I don't have a very good DC system so it would do me little good to do any measurements of airborn dust either size or concentration but when I set up my new shop next years I plan on doing just that. Air filtration system are a good way to cut down on the airborn dust that doesn't get into the DC but again I haven't realy seen any good data colected to determine the effeciencies of these systems.
NIOSH rates resperator under the NIOSH standard 42 part 84
The next best solution is a positive air system where you keep a positive pressure inside the mask. If you are going to get one of these then look for one that is rated at N100 for non oil based and P100 for Oil based aerosoles
Passive systems such asface masks are good only is they fit properly, That mean no facial hair (sorry Jim Becker and a few others) and if they have the proper filters installed. there are filters avaible but I am quite sure that the borgs don't carry them. Look for filters that have an N95 rating. Thats about as good as you going to get. These are rated down to .3 microns and are 95% effecient.
OK now I'll get off of my pulpet.