If you have a deck, playground set, or other outdoor structure that was built before 2004 with pressure-treated lumber, you should pay attention to the new advice from the U.S. Consumer Product Safety Commission on how to mitigate hazards associated with chromated copper arsenate (CCA) used to preserve wood.

As covered in this article on carcinogens and pressure-treated lumber, CCA, used for decades to make wood resistant to insects and rot, was found to contain known carcinogens. While the federal government did not order a recall of CCA-treated lumber, the outdoor-lumber industry voluntarily halted its production for residential use at the beginning of 2004. Also at the time, the U.S. Environmental Protection Agency acknowledged the importance of reducing exposure to CCA.

The EPA and CPSC have since completed a study of stains and sealants. "The new information is that we want people using oil-based or water-based deep penetrating stains about once a year to help people trap the arsenic into CCA-treated lumber that is still out there," says Scott Wolfson, the CPSC's deputy director of public affairs.

Our ratings of deck stains (available to subscribers) include semitransparent stains like the ones Wolfson recommends. Be sure to follow proper safety precautions when working with CCA-treated wood.—Gian Trotta | e-mail | Twitter | Forums

Essential information: Even if your deck doesn't contain CCA-treated lumber, you should perform an annual safety check and clean underneath it. Also check out our report on decking materials.