Hidden Hazards of Halogen Lamps

Why must halogen lamps always be used with a piece of glass in front of them? Because they are hot to the touch running hotter than ordinary incandescent bulbs?
Yes, but the heat causes other, less obvious, even invisible issues that you need to be aware of. Issues that the glass protects you against.
In this video, I take a closer look at them.

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#Halogen #LED #Ultraviolet

[bigclivedotcom]

For reference, I used to use a 500W halogen lamp with no front glass above my workbench in winter for the light and heat. I didn't experience any adverse effects despite it being about 800mm above my head.

[Enjoymentboy]

Back around 93 to 2000 I had halogen track lighting in one room with the lights aimed towards one wall. While the bulbs were replaced a few times they were never re-aimed but none of them had any glass covers...just the bare bulbs. The walls were painted blue and when we finally decided to redo the room we were surprised to see a very clear bleaching of the paint only where the lights had been aimed and it was even more evident where the lights had overlapped each other.

[dino]

The main safety function of the glass cover is to contain the hot halogen capsule glass if it explodes.
There is quite a difference in the front/rear direction heat is emitted between the standard aluminised reflector and dichroic coated glass reflector.
Metal halide lamps emit considerable UV, some types have UV block glass, others rely on the glass on the enclosure.

[aarongreenfield]

Yes do more on the incandescent bulbs please.

[AWcinema]

Thank you for shedding light on this subject😁

[Basement-Science]

In most cases the amount of UVB you can possibly get from halogen lights is so insignificant compared to any amount of Sunlight and cannot give you a sunburn even if it shines on you all day long.

That said, there were also specialized "Sunbathing" halogen lamps that ran so hot they actually looked blue. Very short lifetime on those as well.

[BoHolbo]

Another thing that the front glass on halogen flood lights and the 12V PAR16 lamp you showed us do, is it helps to maximize the lifespan of the bulb by prolonging the cooling time of the bulb glass.

And for the halogen flood light, the front glass will also catch flying glass shards in case the bulb explodes.

[Raintiger]

Awesome video and never something I had thought about before. I worked in a steel mill for nearly 25 years and we used tons of those 500W halogen and many had no glass just to aid in replacement (I, myself, am guilty of blowing up a few halogens in that time by touching it taking it out of the packaging).

[xxxxx]

Recently the US outlawed lots of halogen and incandescent bulbs. But they did not put in an import ban into the law. As someone who sells lightbulbs for a living this is kinda infuriating. People come in looking for a specific bulb and I have to tell them that I can't sell them one but they can order it online from China...

[blueredbrick]

I bought a handheld 1000w halogen lamp from a second had store that specializes in photography. It's tiny, not that long tube format but a bulb type of several cm.
When it's powered up there's seemingly an extra sun under the sky. After a while you can smell litte dust particles just being incinerated. I'm always impressed with that monster light.
I wonder what the spectrum is like.

[Elnufo]

You can see a UV Stop in Halogen Lamps if you shine a UV light source at them, they will glow Blue-ish if a Filter is present.

[Mrdibzahab]

I used to get similar halogen bulbs from the fusers of old laser printers. They were really long, but probably a few hundred watts at most. They scared the hell out of my dutch rabbit once, when she must have thought that the sun moved into my living room.

[faxezu]

The EU ban hit me hard...
But not for private lighting. I'm currently working on my PhD in semiconductor technology and using a sputter chamber.
The tool has a heated chuck to put the wafer on. The heater has to withstand ultra high vacuum and temperatures of around 300°C.
The tool manufacturer decided to use three 400W halogen lamps as heat sources since the glass perfectly isolates the hot metal from the vacuum and thus prevents contamination of my samples.
We build up a stock as spare parts but they break way faster than anticipated...
Without some good connection to a friend outside of EU they would be unobtanium.

[johnnemo]

I was at a fashion show (a long time ago) and the big halogen lamp in a reflector ABOVE the catwalk melted, and the molten glass missed one of the models by just a few centimeters. The lamp was obviously unprotected. Imagine the horror if the glass had fallen on the head of a model.

[hjf]

The MR16 that you noticed filter UV lights are known here as "Dichroic" lamps, the UV light is NOT reflected by the metallized coating, which is a dichroic mirror that only reflects visible light. You may also see a smaller amount of IR with them as well. Try putting your spectrometer to the back of the lamp and you'll probably find your missing spectrum. You can't measure it like you did because the filament is vertical so most of the energy is radiated sideways for the parabolic mirrors to catch. You can also try with an AR111 lamp which is a metalic reflector, not dichroic (AR111 = Alu reflector, 111mm). These are often used in applications where you can't release the heat into the recessed ceiling behind.

[BritishBeachcomber]

I did sometimes get mild UV suntan from working under high power halogen lamps. But not as bad as from arc welding on a hot day without skin protection from the arc .

[Ultrazaubererger]

50h bulbs are actually quite common for microscopes and projectors.
For reference, check out the OSRAM 64640 HLX
There are other versions with 300h and 2000h iirc and they are not that much more expensive.
Although prices might vary quite a bit now as availability gets worse.

[JustPyroYT]

I personally never noticed that halogen lamps are always behind a glass cover...

Really interesting Video! 👍

[erikziak]

What about H4 car lamps? They are halogen too. But only behind a super thin plastic cover. At least on my e-up. But the old Škoda 130L from 1986 has thick glass headlights. Are new cars emitting UV light from their halogen bulbs through their super thin plastic headlights? Or does it filter it out?

[alfepalfe]

I believe some lamps used for photography had super thin filaments for a colder color temperature resulting in an avrage life in the tens of hours, that may be what that is.