Why Some Candles Burn Fast

Q: Does the color of a candle determine whether it will burn faster? Is there some ingredient that makes it burn faster?
Jason, Avilla, Indiana, USA

A:Color makes no difference how fast a candle burns. "Black candles burn no faster than white," says chandler Stefan Phillips of the Island Candle Company.

Wick size is the primary factor determining candle-burning rate. "A larger wick is like stepping on the gas pedal," says Phillips. The big wick delivers more fuel to the burning flame.

By the way, a candle is a cylinder of solid fuel — paraffin wax — that surrounds a wick. How does it burn? Bringing a lit match to a wick melts and then vaporizes the wax coating the wick. The wax vapor combines with oxygen, and burns.

Wax is the most important ingredient that makes a candle burn faster. Soft wax has a higher oil content and lower melt temperature; therefore, it burns faster. Typically, candles in jars have soft wax, and pillar candles have hard wax. The longest burning candles are pillar candles made of a blend of beeswax and paraffin.

Burning tips (from the Island Candle Company):
Trim your wick to 1/4 inch or less before you light a candle. Long wicks burn inefficiently and may smoke.
Protect your candle from drafts, which can blow the flame to one side, and cause molten wax to run down the side of the candle. A dancing candle flame indicates a shortened candle life.
After snuffing out the candle, straighten the curled wick with a toothpick while the wax is soft. A candle with a straight wick burns better and lasts longer.

Further Reading:

Why a candle flame goes up, WonderQuest

If you place a lighted candle in a sealed jar and drop it, why does the candle go out when someone catches the jar? WonderQuest

Tips for taking care of candles: a burning guide, Island Candle Company

Candle burning, Newton ask a scientist

This was the Question of the Month and many readers submitted their answers. Here is one reader's winning entry:
Actually what makes a candle burn faster then others is the type of wick that you use. Sometimes pigment from dyes clog a wick, which can effect the burn time but, more often then not this is not the reason. Wicks are the burn time.
Debi B., Ohio, USA

Next month's question:

Why do people only snore when they are asleep? You breathe all the time, but it's noisier when you are fast asleep. Why?

I'll publish the best answers, and you get credit. Click here - Answer-the-Question - to give me your answer.

(Answered May 7, 2007)