Bright ideas on what to look for, plus tips for safer burning

Which wax to use for candles matters.

Paraffin The most common type of wax, it is also generally the least expensive. Paraffin keeps in shape really well, so it is great for pillar candles – the tall, wide kind.
Beeswax The airy honey-combed kind burns faster than paraffin because it contains less wax. These candles are delicate, so make sure they are well prepared before you carry or store them.
Soy and palm If a candle is made with either of these vegetable waxes, you may see a note on the label. The candles are often found in jars.

Test quality by gently tugging on the end of the wick to make sure it’s secure (You’d be surprised by how many slip out right in the store). A loose one may bury unevenly or, if it falls into a pool of melted wax, not at all.
Look closely at the shape of the wick. You want one that’s braided, not twisted. The braid will help the candle burn slower and with more controlled flame.
Avoid wicks that have metal cores (a sliver of metal in the center). Wicks made with a lead or lead-alloy core were banned in 2003 because they give off unsafe emissions. But these may still turn up on store shelves.

Buy heavy, thick jars. Wax – especially the gooey, transparent-gel kind – can get really hot, so you need a sturdy holder. Make sure you check the glass for cracks and bubbles too.
Throw away the candle when there’s an inch of wax left in the counter. When the flame nears the bottom, it can heat the jar enough to leave a burn mark on the furniture. To be safe, always place candles on a heat-resistant surface, such as a ceramic dish or tile.

Keep candles away from windows, air-conditioning vents, fans and drafts to prevent soot from forming. Every time a candle flickers, that black substance is emitted.
Limit burn time. If you let a jar or pillar candle stay aflame for too long, it can end up lopsided. To avoid that, follow this general rule: Burn up to one hour for every inch of the candle’s diameter (so you’d burn a three-inch wide candle for a maximum of three consecutive hours).
Trim the wick to a quarter of an inch before you light it. The smaller and more controlled the flame, the less the chance of smoke.
Use a snuffer. It can keep wax from splattering when you extinguish the flame.
Be careful with decorations. Trimmings on the outside of candles or items like dried leaves embedded in the wax can catch fire.