Candle makers must ensure candles pass five tests:
- Stability: this is absolutely pivotal to candle safety to check if free standing candles will tip over when lit while on a 10-degree slope.
- No secondary ignition: in some cases, an unexpected part of the candle can catch fire, such as glitter. That’s why candles are monitored to determine whether secondary ignition occurs for more than 10 seconds.
- Flame height: this is an essential part of the testing process. It’s critical that standard candle flame height doesn’t exceed 75 mm and for tea lights, 30 mm.
- Self-extinguishment: when marketed as self-extinguishing, this means that candles both free standing and in a container self-extinguish at the end of their burning time.
- Smoke: this test checks to see if the wick continues to glow or smoke after being extinguished. The limit is 20 seconds.
In order to make it easier for consumers to understand the risks associated with candles, labelling is an efficient way for manufacturers and importers to inform and alert users. European standard EN 15494:2007 (corresponding to U.S. ASTM F2058-07) specifies that the product safety label must include a warning sign as well as compulsory safety information.
The container in which a candle is held is also important as it might be exposed to high temperatures when the candle is burning. But testing for heat resistance goes beyond just the container. Objects located close to a burning candle could catch fire or the container itself could break spilling hot wax. If the receptacle is glass, it must be heat-treated and its thermal resistance will depend on its thickness.
An interesting case in point was in the U.S. this month. The CPSC reported that certain menorahs (candlesticks) melted when the candles were burning which posed a fire hazard. This demonstrates the level of consumer protection in place. First with the U.S. ASTM voluntary standards and then the CPSC whose role it is to keep an eye on global consumers’ safety. They also shed light on bad quality products and warn of the hazards they could cause.
As a matter of fact, testing plays a vital role in business success for manufacturers, since delivering compliant products from the very beginning saves time and money.
Candle testing even includes air emissions and smoke components
Have you ever thought about what you were inhaling when you light or blow out a candle?
Since burning a candle involves emissions, regulatory bodies have also defined standards for soot. The test to detect the quantity of soot emitted by a candle consists of putting a glass plate above the flame for a defined period of time and measuring the transmittance of light through the darkened plate. This is expressed as a soot index. Standard EN 15426:2007 requires that for single wick candles with a diameter up to 100mm, the average soot index for three tested candles should be less than one per hour.
Air quality is also an important part of the testing process. This includes gauging the emission of volatile organic compounds (VOC). Those emissions are particularly important when it comes to monitoring scented candles, because substances like limonene and cinnamic aldehyde may be added to give candles their fragrance.
In fact, the fragrant candle market is massive. Around 10,000 varieties of scented candles are available in the U.S. As a result, extensive research has been carried out to determine whether chemicals created or released during the burning and snuffing out process could lead to potential human health concerns.
The control of VOCs is not mandatory but it is possible regulations will shift in the very near future.
In anticipation of these potential changes, some retailers are already specifying that candles must carry an additional marking indicating the scented candle contains allergenic substances, such as citronellol. This marking is to warn consumers that sensitive individuals should not be exposed to this fragrance to prevent allergenic reaction.
While there may be concern about the use of synthetic additives in candles, it’s important to note that reputable manufacturers only use expertly formulated fragrances specifically approved for candle use. As for pigment and dyes, these are also regarded as safe when used as intended and there are no known health concerns with colourants.
Research focusing on the use of scented candles has concluded that under normal and foreseeable conditions, the use of scented candles does not pose any safety concern to consumers. However, limiting their use in confined spaces is a practical way of avoiding human health issues and allergies.
Tips for safer candle use at home
The CEO of quality control company API Lab, specialists in household goods testing, says, “there is no evidence that clearly attests that the quality of a candle is better when it is organic. Even naturally produced beeswax does not necessarily create a better candle”.
API Lab tests several hundred candles per year and it is reassuring that it remains rare that they fail laboratory testing with a major defect identified. And it is not a surprise when you have a category of products so carefully watched. Those that don’t pass often feature additional elements such as glitter or decorations that might be flammable.
“Knowing more about the rigorous testing of candles is the first step in improving consumer safety when it comes to lighting candles at home. But while these tests and quality controls are there to protect against potential defects or hazardous features, it’s up to the consumer to decide how they want to use them. The same goes for regulations. Consumers should be aware of what controls and guidelines are in place”.
After understanding more about the candle manufacturing and testing process, it might also prompt consumers to consider where they place them? Are they in reach of children or pets? Or close to a source that can catch fire, such as a Christmas tree? And what warnings if any are on the manufacturers’ instructions? Like we said, you’ll never look at candles the same way again.