FAQs

Questions About Candle Safety 

Are scented candles safe? 

Consumers can be confident that a well-made and properly burned candle, whether scented or unscented, will burn cleanly and safely. Although there are no known health hazards associated with the use of scented candles, unfounded concerns about the safety of man-made fragrances vs. “natural” fragrance materials and essential oils continue to populate the media. The fragrances approved for candle usage – whether synthesized or “natural” – do not release toxic chemicals.

Are candles made from petroleum-based products safe?

Validated scientific studies have shown that all major candle waxes exhibit the same basic burn behavior and produce virtually identical combustion byproducts, both in terms of composition and amount. To date, no peer-reviewed scientific study has ever collected or analyzed any emissions data on any candle wax, including petroleum-based paraffin, and proven them to be harmful to human health.

Do candles contain volatile organic compounds?

VOCs are compounds that are composed primarily of carbon, oxygen, and hydrogen that can evaporate into the air. In addition to its evaporation capability, you can identify VOCs by your ability to smell them. Therefore, nearly all fragrance ingredients in a candle are VOCs.

Not all VOCs are bad, unlike what you may have heard on the news.  Every time you walk into a botanical garden or a forest, you are surrounded by VOCs from the plants. Many fragrance ingredients in a candle are identical to VOCs in nature.  Other fragrance ingredients do not exist in nature, but are instead made in a laboratory.

A fragrance’s safety level is not dependent on whether it comes from nature or a lab. It is also contingent on the concentration of the specific VOC in the air.  To ensure fragrances (VOCs) from candles are safe, fragrance formulas are reviewed against the safety standards established by the International Fragrance Association (IFRA).  Each ingredient in the fragrance and the finished product is required to meet the specifications set down by IFRA to be compliant with the standard. If the fragrance and product meet the standard, then the fragrance VOCs in that particular product are considered safe for human use.

The federal government, along with California and several other states, have established VOC regulations for consumer products such as candles and air fresheners.  They limit the concentration of VOCs in these and many other consumer products. These regulations have a very specific definition of what they consider a VOC. VOCs that do not evaporate easily are not considered VOCs under these regulations, but they are still volatile compounds.  These VOC limits on consumer products are not based on any health concerns about the VOCs themselves. Instead, the limits exist to minimize the interaction between VOCs and other chemicals in our atmosphere.

Are scented candles triggers for asthma or allergies?

Although millions of Americans regularly use scented candles without any negative effects, it is always possible that a particular fragrance might trigger a negative reaction in a very small percentage of sensitive individuals. Individuals with known sensitivities to specific fragrances may want to avoid candles of those scents. In addition, consumers should remember to burn all candles, whether scented or unscented, in a well-ventilated area.  

Should I be concerned about lead wicks in candles?

No. Lead wicks have been officially banned in the United States since 2003, and before then they were primarily limited to inexpensive imported candles. NCA members voluntarily agreed to not use lead wicks in 1974, and long supported the elimination of lead wick use.

Do scented candles produce more soot than unscented candles?

The oils found in certain fragrances may slightly increase the small amount of soot produced by a candle, but wick length and flame disturbance are the primary factors that impact sooting in a properly-formulated candle.

Is candle soot harmful?

No. The minuscule amount of soot produced by a candle is the natural byproduct of incomplete combustion. Candle soot is composed primarily of elemental carbon particles, and is similar to the soot given off by kitchen toasters and cooking oils. These everyday household sources of soot are not considered a health concern, and are chemically different from the soot formed by the burning of diesel fuel, coal, gasoline, etc. 

The production of candle soot can also be minimized in the following ways:  Trim the wick to ¼ inch before every use to promote proper flame height, place the candle away from drafty areas to avoid flame flickering, and ensure that the wax pool is free of debris.

What sort of chemical reaction occurs when a candle burns?

When you light a candle, the heat of the flame melts the wax near the wick. This melted or liquid wax is then drawn up into the wick by capillary action. The flame’s heat vaporizes the liquid wax to produce water vapor and carbon dioxide (the same byproducts that humans produce when exhaling).

Questions About Candle Composition

What kinds of waxes are typically used in candles?

The most commonly used candle wax is paraffin. Beeswax, soy wax, palm wax, gels, and synthetic waxes are also frequently used in candles. Different blends of these waxes are popular with many manufacturers.

Are certain types of candle waxes better than others? 

No. All types of quality candle waxes have been shown to burn cleanly, safely and in the same manner. U.S. candle manufacturers select waxes or blends of waxes based on their suitability for specific types of candles or formulation profiles, as well as their own candle-making preferences.

Are candles made with “natural” ingredients or essential oils safer?

Not necessarily. However, NCA members are committed to manufacturing candles that use ingredients known to be safe and approved for use in candles, whether “natural” or synthesized.

How are candles made? 

Although modern technology has introduced greater efficiencies and quality control in candle-making, most candles are made through the timeless process of a wick into wax, which is then molded, dipped, extruded, pressed, rolled, drawn or filled into a desired shape and size.

Is my candle biodegradable? 

Probably. Studies have shown that beeswax, paraffin and vegetable-based waxes are biodegradable. The vast majority of candles today are made primarily from these waxes.

Why do some candles have metal-core wicks? 

Metal-core wicks are sometimes used in container candles and votives to keep the wick upright when the surrounding wax liquefies during burning. Today’s metal-core wicks are made with either zinc or tin. Scientific studies have repeatedly shown both zinc and tin-core wicks to be safe and non-toxic.

I love scented candles. Why don’t candle manufacturers add a lot more fragrance?

There is a maximum amount of fragrance that can be added to a candle before it no longer burns cleanly or properly.

How to Burn Candles 

What causes a candle to smoke, and what can I do to correct it?

A well-made candle will create virtually no smoke when burning properly. Consumers often incorrectly believe their candles are sooting because of the wax type, fragrance, colorants or additives used in the candle’s formulation, but sooting is primarily due to flame and combustion disturbances. If the wick becomes too long, or an air current disturbs the flame’s teardrop shape, small amounts of unburned carbon particles (soot) will escape from the flame as a visible wisp of smoke. Any candle will soot if the flame is disturbed.

To avoid this, always trim the wick to ¼ inch before every use and be sure to place candles away from drafts, vents or air currents. If a candle continually flickers or smokes, it is not burning properly and should be extinguished. Allow the candle to cool, trim the wick, make sure the area is draft free, then re-light.  

How long should I burn a candle?

Maximum burn times vary from candle to candle, so it is important to follow the manufacturer’s instructions. Always extinguish a candle if the flame gets too close to the candle holder or container. For a margin of safety, discontinue burning a candle when 2 inches of wax remains (½ inch if a container candle or jar candle).

How can I tell if I’m buying a quality candle?

Unless a candle has defects that are obvious to the eye, you probably can’t tell just by looking. That’s why the National Candle Association strongly recommends that you purchase candles from a reputable manufacturer. 

All NCA members adhere to ASTM candle standards and have pledged their commitment to quality products and practices. Be sure to visit NCA’s Directory of Member Candle Manufacturers and their Brands.

Why are candles so popular?

Candles are one of the most enjoyable, affordable, and readily accessible luxury items. They infuse the home with color and fragrance, and can help create a special warmth and ambiance to allow for a sense of calm and well-being.