According to YSK, candle wax is very combustible and should be regarded like a grease fire if started. Why YSK: If candle wax reaches its flash point (about 400F) and catches fire, blowing on it will generate a bigger flame and distribute droplets of burning molten wax all over the place. This can lead to serious burns for anyone who comes in contact with them.
Although you cannot see smoke when melting candle wax, there are many compounds present in it that are highly flammable. As you heat up any compound, it will change from a solid to a liquid then to a gas. Each phase has its own characteristics so being able to identify which ones occur during melting is important in determining how this material should be handled.
The first thing to go up in smoke when melting candle wax is any loose material such as threads or dust. Next come any large pieces such as wicks or pins. Last come the small particles such as polymers that may not smoke but burn with an intense odor that could be detected far away from the actual melting process.
When melting candle wax, only use ceramic or glass containers because metals can melt at different temperatures depending on the metal content. Also, keep in mind that some materials may appear to be harmless as long as they are not exposed to oxygen; for example, wood is usually not a problem as long as it is not lit.
Candles are a brilliant innovation. The fuel is wax, however it can only burn as a vapour, therefore liquid and solid wax will not burn. When you light a candle, the solid wax around and around the wick melts. The heat from the flame then continues to melt more of the wax until all that's left is a pool of melted wax, which is able to float on top of some liquid additives such as paraffin or soy.
As the candle burns, its shape is preserved due to the resistance of the surrounding wax. As the wick reaches the end of its lifespan, they become too small to support their own weight so they collapse into the bottom of the container they were in. This does not affect the quality of the wax, just the wick itself so another wick can be added and the process can continue.
When a candle burns down to its base, there are two possible outcomes: either the wick has been removed before this point, in which case the candle is said to have "gone out" (or "been extinguished"). Or the wick has been burned down to its base at which point it will no longer support burning and will eventually drop into the pool of melted wax below. In this last case, the candle is said to have "died".
Although paraffin wax used in candles is combustible, it does not burn easily. As a solid, the wax must be heated sufficiently to transform into a gas (turns to vapor). The flashpoint of paraffin wax is 392 to 480 degrees Fahrenheit (200 to 249 Celsius). Above this temperature, it will burn if exposed to air.
Wax has many applications in industry and technology. It is used as a protective coating on instruments and machinery, from typewriters to steam engines. Paraffin wax is also used in making candles, which are widely used for decorating events and holidays, as well as for energy savings. There are several types of candles, including molded, rolled, stick, flower, fruit-based, and soaps.
Candles are made by mixing petroleum products with some type of fuel oil or natural wax, then heating the mixture until it melts and becomes liquid. The resulting material is called "wax." Most candle wicks are made from cotton or linen, but wood, bamboo, and hemp are also used occasionally. When burning, candles produce large amounts of smoke, most of which is carbon dioxide. Some other gases that may be produced include water, sulfur compounds, and alcohol. During World War II, when petroleum products were scarce, beeswax became popular as a replacement for paraffin wax because it does not produce smoke when burned.