Doctor's Orders

Because I was already sensitized he recommended immediately having someone else vacuum everything in my home with a strong vacuum that either exhausts outside or uses a HEPA filter. To clean my shop he recommended I wait for a breezy day then have someone else put on a mask, seal off the house, open the big garage doors and side door to my garage based shop, put a big exhaust fan in the doorway that worked with the wind direction and then thoroughly blow out my shop with my air compressor or leaf blower going over and over things until seeing no more dust. After the shop was blown out leave all open and let the big exhaust fan run for at least four hours. After that fan cleared the airborne dust, close all down and let whatever dust was left settle for at least a day. Then again have someone else use a powerful vacuum to clean all while either exhausting outside or through a HEPA filter.

My respiratory doctor used to tell his woodworker patients to always wear a good fine filtered mask and always use a large exhaust fan to clear out the air from our work areas when making fine dust. Years later after working with me on this dust collection site my doctor changed this recommendation. He recognized that letting fine dust loose in our woodworking environments is unacceptable because even with a good exhaust fan it takes months to years for this fine dust to break down and dissipate so every time we use our shop we get exposed even when not making fine dust. Because fine dust rapidly spreads in any shared air and is easily carried on our hair, skin and clothes, it often contaminates not only our shops, but our vehicles and all areas we visit which will continue to cause harm to us, all close to us, and even our pets. He now tells his patients that safe woodworking requires us to control the fine dust as it is made, capture it at the source, then immediately get rid of it so it never gets into our shop air! When we cannot keep from spraying the fine dust into our woodworking environment, we must take our work outside with our masks on.

Whether we own a dust mask or powered respirator we must regularly wipe them out with a non-alcohol pad to keep them clean. We also must change the cartridge filters when needed. Activated charcoal filters and many other types of mask filters lose effectiveness when exposed to air whether we are wearing them or not, so my doctor recommends storing our masks in a Ziploc airtight bag. When he puts his mask in its bag he sucks most of the air out to maximize filter life.

My respiratory doctor said even when working outside, whenever I made fine dust that was not being immediately captured I needed to use a fan. He recommended using a good heavy duty stand mounted oscillating fan with the oscillation feature turned off. This fan must be set to blow the dust away from me as I worked to keep me from breathing it and to help keep my clothing clean. My respiratory doctor also recommended I use this good sized fan in the back doorway of my shop with the garage door open a little whenever making fine dust to keep that dust from building in my shop. I have to sometimes make the fan in the doorway blow outward and other times blow in depending upon the local wind direction. In the few instances where I mess up and fill my shop with fine dust he recommended I use that fan on high with all doors open wide while also running my air cleaner and cyclone with fine filters, then after all settles vacuum all with my HEPA filtered vacuum.

A few of my friends also recommend using in every shop that is attached to our homes an exhaust fan wired to turn on whenever we turn on the lights. If we have all doors and windows closed and run that exhaust fan to the outside it will create a negative pressure. This fan does not have to exhaust any air. A small bathroom exhaust fan creates enough negative pressure to keep a blast of dust filled air from contaminating our homes when we open a connecting door between our shop and home.

My respiratory doctor says ideally we would all do just like commercial shops and just blow the finest dust away outside. Although most small shop woodworkers should exhaust their shop air outside, most do not. He said there are many excuses and reasons to vent indoors, the main one being that it is easier. Venting our dust collectors and cyclones indoors even with fine filters causes our shops to build up dangerously large amounts of fine dust. Venting inside also increases our risks as most dust collectors and even cyclones come with collection bins that are not fire proof. There are a few good reasons to not exhaust outside and many better reasons to do so.

1. In some areas like mine venting outside is illegal. Although this is what I heard from my County building inspector's office, it turns out that it is illegal only if I am a commercial firm, so is not enforced for small shops. This is one of those things that upset me considerably because I tried to do all right, got bad advice and spent a lot of time and money that really was not necessary.

2. The noise can upset neighbors. Adding a little sound proofing either around our dust collection equipment or storage shed, plus using a good muffler, homemade or commercial will address most of the noise issue.

3. Too many small shop owners foolishly worry about blowing the heated air out of their shops when commercial firms have shown that doing so really is not as expensive as trying to filter the air. Large commercial shops with huge blowers that turn over the entire air volume many times every hour have known for years a good radiant heater will leave us feeling little discomfort unless it is below freezing outside.

4. Our hobbyist dust collectors and cyclones are built for indoor use. Repair is as easy as providing their own shed or covering to place our dust collectors and cyclones outside. Many simply choose to keep their cyclones inside and vent outside.

5. Also, a good many of the woods used in woodworking today can kill our landscaping plants, and can harm our pets and children when they play outside. Repair is fairly simple, use a cyclone separator to remove the heavier sawdust and chips. The remaining fine dust will dissipate in the outdoor air without causing problems.

6. Finally, Unless we provide a way for makeup air to enter our shop, blowing the air outside can suck deadly carbon monoxide backward through our vents. Most need to just open a door or window and they the risks of pulling the carbon monoxide out of our fired appliances vanishes.

My respiratory doctor and many safety organizations warn our dust fans, exhaust fans, dust collectors, and cyclones can pull deadly carbon monoxide backward through the vents from our gas water heaters, heaters, fireplaces, furnaces, and other fired appliances. I found my shop exhaust fan and dust collection blower pulled carbon monoxide from my attached home furnace. My doctor strongly recommends every small shop woodworker install good quality carbon monoxide detectors in their home and shop to immediately know if we have a problem.

My respiratory doctor recommends we buy filters with enough surface area and ample fine filtering. Unfortunately, most small shop filters provided with dust collectors, cyclones, air cleaners, and even shop vacuums are too open so pass most of the unhealthiest invisible dust plus have too little surface area so clog constantly requiring frequent cleaning and quickly wear out.

My respiratory doctor next told me to go buy or build a good quality down draft table and always use it when sanding. I looked at him kind of funny because he has been bugging me for years for a set of plans for the down draft table I built ages ago. We both have long known that there are no good affordable hobbyist downdraft tables. I teased him back saying he was the one who made the big bucks. After looking suitably hurt, he smiled and said if I built another, he could have my old downdraft table and I would get a new one. The projects area of my index gives directions on how to size and build your own downdraft table.

Years after putting up these web pages my respiratory doctor now recommends every woodworker have and use a good portable hood connected to our dust collector. Too many large tools, smaller power tools, and even hand operations generate lots of fine dust. Often even a downdraft table is not enough to provide good fine dust collection unless we also use a portable dust collection hood placed right next to the dust source. He recommends buying or building a stand that supports this hood and permits positioning it right next to our woodworking operations. I found having both a stand and gluing a few powerful rare earth neodymium magnets to my hood lets me cover almost any need firmly holding the hood right where it is needed without slipping.

My doctor also reminded me to not only wear my apron, but also when making fine dust to wear a cap, light jump suit, and bandanna that I take off before going into my home. This keeps the fine dust from being tracked all over. He also recommends wearing wear gloves and good skin protective clothing when working with the more toxic woods.