Refinishing Floors Safely
Refinishing floors is not inherently dangerous. Nonetheless, there are safety issues to consider.
Electrical. Before renting sanders, examine their electrical cords and plugs, rejecting any that are frayed or appear to have been sanded over. If you don’t have a heavy-duty extension cord, rent or buy one; lightweight household cords could overheat and start a fire. User’s manuals or labels on big sanders indicate minimum cord specs. Household circuits must be adequately sized for the equipment: 220-volt drum sanders often require 30-amp circuits; 110-volt sanders typically require 20-amp circuits. In most cases, a drum sander’s 30-amp plug will fit a home’s 30-amp dryer receptacle.
Volatile chemicals. Finish manufacturers have reduced the volatility and strong odors of their products, but you should always limit your exposure to them by wearing an organic-vapor respirator, long sleeves, and gloves when sanding old finishes or applying new ones. Even fumes from water-based polyurethane are unhealthful to breathe, so as soon as finishes are dry to the touch, open windows to let vapors disperse. And sleep elsewhere till they’re completely dry.
Fire and explosion hazards. Sparks or open flames can ignite chemical fumes or dust. So before you start sanding or applying finish, turn off pilot lights for water heaters, ranges, and furnace. Also tape light switches down so they can’t generate a spark. Trash bags of moist sawdust or covered garbage cans full of oily rags can generate enough heat to combust spontaneously, so don’t allow debris to collect on site. Empty sander bags often into a metal container safely away from the house and other combustibles.
Lead paint and asbestos. Floors painted before 1978 may contain lead-based paints, so don’t sand them till you’ve had the paint tested. Lead paint is generally not a problem until the dust becomes airborne or it flakes in an area where small children might eat it. Old linoleum floors may have been adhered with asbestos adhesive, which wasn’t banned till 1977. Here again, asbestos is usually harmless if undisturbed, so first consult a local health department to get the name of a test lab.
This blog is adapted from Renovation 4th Edition, which contains thousands of field-tested tips and techniques from master builders across North America. Renovation 4th Edition‘s 614 pages include 250+ technical drawings and 1,000 photos selected from the 40,000 that I have taken over the years. I hope you find it useful. -Mike
© Michael Litchfield 2013
Renovation 4th Edition contains lifetimes of experience: thousands of field-tested tips and techniques that master builders across North America shared with Mike Litchfield, a founding editor of Fine Homebuilding.
To prevent sanding over the cord, keep the excess looped over your shoulders. Drum sanders sand whether you're going forward or backing up, so as you back up, continually pull the cord away from the path of the sander.