Candles poured in glass containers or placed into glass dishes or trays for use as centrepieces must be properly maintained to avoid fires from breaking glass. The U.S. Consumer Product Safety Commission has collected many reports on candles in glass containers breaking and causing injuries. In 2004, the National Fire Protection Association estimated that candles were found in seven out of every 10 homes. Take proper precautions to avoid a candle-related fire caused by the breaking glass of a centrepiece.
Types of Candles
Candles such as pillars, votives, tarts and tapers are sold without containers and are intended to be placed onto or into a candle holder or other container for burning. Wax or gel wax is poured into containers made of ceramic, glass or metal and are considered poured container candles. Poured wax candles often come in glass jars, glass canning jars, ceramic or china containers, or thin glass containers. Centrepieces are often created using one or more candles in containers or placed on candlesticks. Decorators often place faux flowers and other decorative accents around the candles to embellish the centrepiece.
Heat-Related Glass Expansion
Poured container candles in glass containers are at risk for breaking when the heat from the burning flame and hot wax reaches extreme temperatures. The U.S. Department of Energy explains that when glass heats up, it expands, and the brittle nature of glass doesn't allow for very much expansion before the glass cracks or shatters. Candles burning on glass trays, plates or other items can cause the glass object to expand and break.
Direct heat from the candle flame may cause glass to break. The longer the wick, the more the flame is able to burn against the glass container holding the burning wax, so keep wick lengths to no longer than 1/4 inch. State Farm Insurance warns against placing candles in narrow-mouth glass containers, which can easily make contact with the candle's flame. Avoid burning a candle for longer than four consecutive hours to reduce the likelihood of glass overheating and breaking.
Glass Candle Centerpiece Hazards
Centrepieces with faux foliage or flowers or other decorative elements around candles are at a higher risk for fire if the candle's glass container breaks. These embellishments can catch fire quickly. NuScents Candle Supplies recommends placing multiple candles at least 3 inches away from each other to reduce heat build-up between the candles.
Never place candles in or on top of cracked or chipped glass items. Heat can cause further expansion of these blemishes and cause the item to crack or shatter. Do not burn poured glass container candles if there are any cracks or chips in the glass.
Avoid breaking glass and fire hazards by following the extinguishing standards established by the National Fire Protection Association: Extinguish a pillar and taper candle when the candle is 2 inches taller than the container holding it, and extinguish a poured candle when the wax at the container bottom is 1/2 inch deep.
Proper Maintenance of Glass Candle Centerpieces
Be careful what you select to embellish your centrepieces. Paper flowers, doilies and ribbon are at extreme risk for burning. State Farm Insurance recommends placing candles at least a foot in every direction away from flammable objects. If you see the candle flame burning too close to the glass, or burning irregularly due to air circulation from vents or windows, extinguish the candle. Use trays or candle holders manufactured for the purpose of burning candles instead of glassware such as dinner plates or serving trays. Make sure the surface beneath the centrepiece, candle and holder is level. Place a heat-resistant material beneath the centrepiece to protect the table or counter.
- U.S. Department of Energy; Ask a Scientist Thermal Stress and Glass; Jim Swenson, et al.; July 20, 2004
- National Fire Protection Association; NFPA Study Shows a 15% Increase in Candle Fires from 2000 to 2001, Triple the Number in 1990; September 20, 2004
- State Farm Insurance Company: Candles and Fire Safety
- NuScents Candle Supplies: Candle Making Safety Tips
- U.S. Consumer Product Safety Commission: Lumetique Recalls Botanika Candles Due to Fire Hazard; May 12, 2009