Shattering lightbulbs and light fittings

We’ve had reports of lightbulbs shattering unexpectedly when in use, whether they were halogens, CFLs or LEDs. Not just flickering or dying, but actually cracking or shattering. We’ve also had reports of light fittings shattering, especially small enclosed glass fittings that can crack from the trapped heat of the lightbulb inside.

Our lightbulb buying guide notes that small enclosed light fittings can trap heat even from a CFL or LED light bulb and reduce its life, so a halogen lamp, which is less susceptible to heat, may be the solution in that case. Or, get a new light fitting that’s not enclosed and won’t trap the heat.

Shattering lightbulbs and light fittings are obviously a hazard. Have you experienced this problem? Do you think that all LED and CFL lightbulb packaging should carry a warning to not install them in an enclosed light fitting, or state clearly whether they are suitable for that purpose?


Hi @ChrisBarnes, clearly if there is a danger of injury to a person or damage to property (rugs for example) associated with the failure of the product then the buyer should be aware of the limited, but safe use, of the product. This, of course, begs the question of whether they should be on the market at all. Normally when a product can fail catostrophically it is subject to a recall. Is this a design fault you are describing or simply misuse of a product caused by a lack of information? In short, as a minimum, clear, unambiguous warnings should be provided however my preference would be to see a re-design of the product to prevent the failure.

I hate to “burst your bubble” so to speak but halogen bulbs may not be the answer either. I have a ceiling fan with 3 open ‘cone-shaped’ glass light fittings beneath the fan. In each of these I have a 28 watt, small Edison screw halogen bulb made by a brand I have used continuously since the fans were installed nearly 10 years ago. Recently I turned on the light as usual and the globe (and therefore the glass fitting) exploded in small shards in every direction. The rest of the globes and fan continue to work perfectly. There does not appear to be any reason why the bulb should have exploded but the glass was very hot when I attempted to pick it up from the floor.

Maybe the issue is not the enclosure per say but poor ventilation. Having a good enclosure in the ceiling which is covered by insulation will also cause overheating of the globe (irrespective of being halogen, CFL or LED). Maybe it would be better to have a caution statement which states that the bulb, should be adequately ventilated to prevent overheating. Overheating may cause premature failure, bulb disintegrating or fire.

I can see having a statement about enclosures suitable for purpose may trigger some electricians to unnecessarily recommend the replacement of enclosures when retrofitting energy efficiency lighting because they are older and don’t have a corresponding suitability statement…rather than ensuring the existing enclosures are free from dust, insulation etc and well ventilated.

The other question, if the disintegration solely due to heat buildup and/or from say a manufacturing fault which can lead to the failure? These are different and if mainly the later, could result in unnecessary cost to the consumer.

The other risk with unenclosed fittings in the ceiling is over the extra long life of a bulb (esp. CFL and LED), there will be significant dust accumulation which will affect ventilation and increase fire hazard.