Candle Makers Take Heat on Ghosting

Lack of access to oxygen can cause overproduction of soot. Jar candles like this one are especially prone to the problem.

Not every candle burns the same. Ron Bailey of Bailey Engineering in Palm Beach Gardens, Florida, says that certain candles are more likely to "burn dirty," or manufacture more soot, than others.

Several things can cause the production of soot. There's conjecture that it may have something to do with the grade of paraffin or the use of oils for scented or aromatic candles. Paraffin is a petroleum product, and cheaper, less-refined paraffin has greater concentrations of petroleum. The evidence suggests to some that these are both real possibilities, since instances of staining have become more frequent in the last few years, as sales of aromatic candles have shot up. Marianne McDermott, the executive vice president of the National Candle Industry, says, "The candle industry has gone through an incredible boom in the last two to three years, primarily due to an increase in sales of scented candles, which are very popular. The increased business has spurred a lot of new manufacturers to get into the business, and an increase in imported candles coming into the country."

Jim Becker, former chairman of the technical committee of the National Candle Association, says that no conclusive research has been done to show that the paraffin mix causes candles to produce more soot. "Paraffin wax has some oil in it because it's made from petroleum oil. A fully refined paraffin wax has less than 0.5% oil in it. There are different grades of wax that can be used. A scale wax is the next grade up, and that has less than 3% oil. Another grade has less than 10%. I have never seen a test result on the amount of soot related to the amount of oil. I've never seen anything that says more oil means more smoke or soot."

Becker says, however, that other factors--like the length of the wick and the flame's access to oxygen--can cause overproduction of carbon particles. Candles inside glass jars often produce more soot than free-standing candles because, submerged in the jar, the wick has limited access to oxygen (see photo). If a candle is designed incorrectly, the wax will melt faster than the wick can burn down, so the wick is frequently too long.

"Normally, the main thing that will cause a candle to smoke is an oversized wick, which will cause the flame to burn very high," Becker says. "Any little draft will cause that candle to smoke. There are some candles on the market that are not designed properly, but even a well-designed candle will smoke if there are drafts."

Becker and McDermott both say that the soot staining problem is relatively new to them. However, several candle manufacturers are taking note of the problem in the warning labels on their product. Banana Republic, owned by The Gap, is currently under litigation by a consumer who says she experienced significant property damage to her house after burning some scented candles bought at Banana Republic. The consumer filed the original claim in September 1997, and now The Gap's scented candles contain a warning label recommending that the candle only be burned for two hours at a time. The new labels also caution that the candles can result in "personal injury and/or property damage."

Debbie Gardner, spokesperson for The Gap, says that she can't comment on why the labels were changed, because it is related to ongoing litigation. She adds, however, that "labels are continuously updated to make it more appealing and clear to the customer about how to use the product."

Other manufacturers and distributors have made similar changes to their labels, among them Candle-lite, Crate & Barrel, and Burdine's.

What may have started out as an interesting tale in the annals of building science is fast becoming a hot topic for the mainstream media, the candlemaking industry, and the courts. Litigation is under way in several states, against both candle manufacturers and builders. In some cases, the recent research is being used as a defense for builders who say they're not at fault, and in other cases it's being used to pin down candle manufacturers who may be producing inferior products. Stay tuned.

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