100 watt lightbulbs are dangerous for home use?

I was buying some today which I use in my outdoor light by the backdoor to keep burglars at bay. The grocery clerk who checked me out told me not to use these as they can burn the wires in the fixture and start a fire. Is this true? If so, why do they sell them at a grocery store?

For the same reason they sell matches, knives etc. It’s about personal responsibility. Some bedside type lamps can handle nothing over 40w, but an overhead light fitting should be good for 150.

They are not dangerous if the fixture you’re using is rated for 100W light bulbs or higher. They will melt stuff if they are placed in fixtures that are not rated for a wattage that high. Same goes for power strips and extension cords.

It really depends on the fixture and what it calls for. A lot of my ceiling fixtures call for nothing larger than a 60 watt but thats because the bulb sits so close to the fixture. A 100-watt bulb should be fine in certain lamps where the shade is far enough from the bulb or the bulb isn’t in close contact to a surface.

In some fixtures, there’s a warning against using bulbs over 60w. The grocery clerk (who thinks he’s an electrician) might have expanded from those warnings to think it applies to all fixtures. It doesn’t. However, if your fixture has such a warning, you can safely substitute a Compact Fluorescent Bulb of 26w. That will give you the same brightness you had from an old-style 100w bulb.

In the past, I confess I have used bulbs bigger than the warning approved. I didn’t burn down the house, but I might have been stupid-but-lucky.

I’m not an electrician, either, so apply salt to taste.

There are actually two separate overheating issues, here. First, the heat of the bulb itself might damage some fixtures. Second and more importantly, though, if the wires connecting to the bulb aren’t rated for that current, they can overheat, too, damaging things inside the fixture, or near the power cord, or inside the wall. That said, if everything is rated for the power you’re using, then there’s no problem. And as AskNott says, it’s the power that’s relevant, not the brightness, so a compact fluorescant can be safely used in almost any fixture.

Which is good advice for everyone, everywhere. CFB’s use less energy, put off less waste heat (thus lower fire risk) and save significant amounts of money over their quite-lengthy service lives by being more efficient. There is no reason to buy incandescent bulbs instead of a CFB. Whatever you think you’re saving at the register you will pay out several times in your electric bill.

Yes, there is at least one good reason not to, for some - the quality of light is unacceptable to me in terms of brightness and colour.

All your other points are very valid, but please note there are valid reasons some people don’t embrace CF lights.

Let’s not go crazy here, there are still plenty of reasons (personal preference of light spectrum, instant full brightness, cold weather performance, lower initial cost to name a few) , but as a outdoor fixture security light CF bulbs would seem like a much better choice, almost ideal unless it is in very cold temperatures (reduces light output), and as long as the bulb fits you should be able to get 100W of light output with using about 1/4 the power.

Were you buying these light bulbs from the grocery area in Walmart ?


I have some light fixtures removed from service which I use to drive home the point in adult evening education. The paint is burnt off the back of the fixture, the aluminized reflector is scorched, and the fixture wires have hardened, broken insulation.

Unfortunately, I find this scenario too often in the homes of elderly people, who want to brighten things up a bit to compensate for failing eyesight.

Since it’s Fire Prevention Week, take a few minutes to see if any of your fixtures are overlamped, and if you have elderly neighbors or relatives who live alone, checking their residence for this potential ignition source could be a life saving gesture.

All lamps have a maximum wattage. Don’t exceed it and your fine.

Most of the ceiling fixtures have a 60W max rating, but always check the fixture.

I guess the 200, the pair of 150s, and the 3-way 75-150-225 I had in my dorm room was downright arsonistically suicidal, then?

There are CFLs made to duplicate other colors, including incandesent and “natural”.

I need a good bright light to read (many of my books have small-print footnotes, etc). I have yet to find a CFL which can adequately replace the 150, 200 bulbs that I normally use.

  1. CFLs are advertised as such, but they still are not an exact match.

  2. If anyone on this board can be assumed to know this, it is Una.

I agree with this. I have a ceiling can fixture above a Jacuzzi-type tub which
will not take a 100-W bulb. Yet a 75W incandescent puts out more light than
CFLs which supposedly replace a 100W incandescent.

That said, I use CFLs for most purposes, especially in the summer, when the
reduced production of waste heat is a plus.

I thought people didn’t embrace them because they could get electrocuted in the shower. :slight_smile:

They also give off a LOT less light than they are rated for. I bought a 23 watt CFB bulb that claimed to be the equivalent of 100 watt incandescent and I actually measured it (with an oil-spot test) and it gave about 2/5 as much light. It was new and the incandescent bulb was not, incidentally.

This is quite correct - but wires insufficient to carry 100w would be shockingly substandard.