Candle Safety
Whilst the great majority of candles sold are well designed and burn normally, a small proportion exhibit abnormal burning behaviour.
A few examples are provided below. (click on a photo for a larger view).
Gold coating
This candle was coated with a metallic gold finish which tended to accumulate as a residue as the candle burned down. In this case the residue tended to provide a wick-like matrix that ignited and burned with large flames causing rapid melt-down of the wax.
There was a risk that the burning gold residue could be carried along by the flow of melting wax and become deposited on surrounding furnishings with the risk of fire.
Inclusions
Some candles contain materials in the wax for decorative purposes. In this case, the inclusions ignited providing a large secondary wick with large flames that caused the candle to melt down and release a flow of molten wax.
As above, this candle also contained inclusions that ignite and caused massive melt-down. Inclusions should remain within the un-melted section of the wax as the candle burns down and they should never be capable of operating a a wick to support a sustained flame.
Wick curling
Wicks are designed to bend as they burn down but in come cases the extent of the bending make the wick curl in a tight circle.When this happens, it may cause an enlarged wick flame or a section of the wick may detach and fall, still burning, on surrounding furnishings with the risk of fire.
Wick Nodules
Some candles produce carbonised nodule on the wick. These nodules may eventually oxidise leaving no trace. But in some cases the nodule may fall of and, in this case it has become attached to the side of the candle, still burning and gradually sliding down the side of the candle.
This can release a flaming ignition source onto surrounding materials.
Gel Ignition
Gel candles may operate at a higher temperature than similar wax candles. In this case the temperature of the gel exceeded its ignition point and the surface of the gel ignited causing large flames and the container became very hot.
In some cases, glass containers can fracture releasing very hot gel which may cause burns injuries if it comes into contact with the skin.
Wick Fragment
In this case a fragment of wick was present in the wax of the candle and it became exposed as the candle burned down.
The fragment ignited producing an enlarged flame which made the candle melt down more rapidly than normal.
Tea-light flare-up
In common with all candles in containers, tea-lights can undergo wax ignition if the wax temperature exceeds its ignition point, about 220 deg C.
This can happen if a foreign object is present in the wax such as a spent match. This photographs shows such an event. The tea-light underwent wax ignition as a result of a spent match being disposed of by being left in the tea-light.
In this case the temperature of the wax rose to over 350deg C.
Glass breakage
Filled candles often employ glass as the container material. The glass will usually get quite hot under normal burning conditions but in this case the wick was displaced and the flame came into contact with the glass causing it to break.
In some cases the glass can shatter and release the burning contents.