WoodFinishing & Furniture Restorer's Supply



In an effort to be a little greener, and keep you a little safer, we're going to be posting the Material Safety Data Sheets here in the near future. That way, you'll always know where to find them, and we won't need to clutter your shipments and your file drawers with even more paper.




Here is an interesting discussion link regarding Potassium Dichromate, which appeared in Woodworker's Journal regarding the use of chromium (an historic material used by woodworkers) in your work.

Here is the meat of the discussion presented in the Woodworkers Journal article:

Potassium Dichromate
As is always the case, any discussion of a material that is somewhat hazardous generates comments and strong opinions on both sides. So it was when we broached the subject of potassium dichromate, used to color tannin-based woods. Even lye, mentioned in passing, got into the act. Here are some additional comments. Editor

"Let me weigh in on the dichromate issue. I am a practicing chemist with 30 years industrial experience. Potassium dichromate is a strong oxidizer. It contains the chromium (VI) ion, a known carcinogen. However, it is only a carcinogen by inhalation. It is dissolved in water, after which it is no longer an inhalation hazard. Once applied to wood, it is itself reduced so that it is no longer chromium (VI) ion, and therefore any dust produced at this point should not be carcinogenic by virtue of the dichromate. Wear gloves and goggles and be careful. All chemicals should be handled with care, but this one is quite useful and, like many things, its danger is somewhat over-hyped. It really makes for some knockout stain for curly maple." Sam Whitley

This, of course, assumes that 100% of the dichromate reacted with the tannin. In our opinion, you are wiser to assume that the dried residual dust from sanding may also contain unreacted chemical, and you should wear a respirator as well as goggles and gloves when sanding the dried, treated wood. Editor

"Potassium dichromate should be no problem if used properly. Use gloves and safety goggles and be careful not to splatter or spill. Don't mix it with anything combustible because it's a very strong oxidizer, and in the right circumstances, it will actually cause a fire, such as if it were mixed with moist sawdust. To dispose of it properly, call your local hazardous waste facility. Drain cleaner (lye) is mostly sodium hydroxide, not potassium. Drain cleaner makers try to maximize their profits, and sodium hydroxide is much cheaper than potassium. At any rate, both sodium and potassium hydroxide are similar in their action on wood. They are also similar in their hazards to humans and animals. You must be very careful not to let it contact skin or especially eyes."
Craig Erickson