With all the practical, health, and safety concerns surrounding methylene chloride, it's not surprising that some manufacturers have come up with alternatives. The most common now on the market is N-methyl pyrrolidone, often called NMP. Unlike methylene chloride, NMP evaporates very slowly, so it remains active on paint long enough to soften and release many layers at once. The key with NMP is patience; it needs more time to work than methylene chloride.

"There's no quick bubbling," says Janice Nachbar, national sales manager for the Back to Nature line of NMP strippers. "It's not burning up the paint, just dissolving the binders—the oils and latexes that keep a paint film intact." Painting and decorating contactor John Dee, who has used NMP strippers on several projects, has found that he can spread them over a larger area with little risk that the solvent will evaporate before he has time to remove all the softened paint. And because there's no waxy residue, he can go right from scraping to painting with no intermediate wash. "It's very wood-friendly," he says.

But as far as being people-friendly, NMP has a mixed scorecard. Claims that it's safer than methylene chloride are based on its low evaporation rate, which does minimize the risk of inhalation unless the stripper is sprayed. Still, NMP should be used in a well-ventilated space. Also, the liquid is a skin irritant, and it can cause a burning sensation for up to two days after initial contact unless quickly washed off with water. Dressing in sleeves and trousers reduces the chance of NMP getting on skin, but the only suitable protection for hands is butyl-rubber, nitrile, or neoprene gloves. "Latex gloves like you get at a supermarket are not enough," Gilles says.

The group of solvent-based strippers known as dibasic esters, or DBEs, is another of the "safe" finish removers now on store shelves. Like NMPs, with which they are often paired, DBEs evaporate slowly and can work through many paint layers at once, although it takes even longer than NMP. When using DBE strippers, contractors will often paint on a thick layer and cover it overnight with plastic wrap. When it comes time to remove it, the gummy residue clings to the wrap, making scraping less messy.

DBEs have long been used in hand cleaners, and have been marketed as the "safest" of all strippers. But the CPSC became concerned about those marketing claims after some people reported blurred vision when working with the solvent in poorly ventilated spaces.

Industry-sponsored testing in conjunction with the Environmental Protection Agency is underway to confirm or refute those reports; final data are not yet available.
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