[UVC SAFETY WARNING] strange UVC lamp from AliExpress

[Fandyus]

UV SAFETY] UV-C Light Is Dangerous

 

NEVER look at a UV-C light.

NEVER let UV-C light hit your skin or eyes directly or by reflection.

UV-C light can cause:

• severe burns of the eyes and the skin, and
• DNA damage from broken chromosomes.

When working with UV-C illumination, you MUST:

• cover up completely, 
• wear head & eye protection, and
• have strong ventilation.

 

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Hello there. It's been a long time since I posted. Life got in the way. But this video just came in and it is honestly a little bit concerning.

Brainiac75 tests the output of halogen lamps and finds out they emit a small amount of UVC. I have an unfiltered 125w spotlight that I have used a few times as a lightsource and I am wondering what the implications of this are.

 

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So I was browsing AliExpress for fun last night, and I ran into this.

https://www.aliexpress.com/item/4000805185239.html?spm=a2g0s.8937460.0.0.2f5b2e0eAat3SH

It's extremely cheap and if you would have shown me this and asked me what it is, I would say it looks like an incandescent lightbulb judging off of the looks. But it's not? I have no idea what this could be, is it simply filled with mercury vapor and there's a current jumping between the two electrodes? Also they sell a "With Ozone" and "No Ozone" versions which confuses me further.

I wont buy it since I don't own any UVC safety gear, but I'm still curious.

[Andy Perrin]

I can’t even see it because I get a big “This item can’t be shipped to the United States.”

 

Can you post some screen caps?

[Fandyus]

Here's an alternative link.

https://www.aliexpre....1ccb2e0e3rkeHz

But just to make sure, here's the screenshot.

[Stefano]

From here:

 

"An older design looks like an incandescent lamp but with the envelope containing a few droplets of mercury. In this design, the incandescent filament heats the mercury, producing a vapor which eventually allows an arc to be struck, short circuiting the incandescent filament".

 

I think that's what it is.

[Stefano]

David knows very well the difference between ozone-free and ozone-producing. It is about blocking/allowing the 185 nm line.

[Andy Perrin]

Yeah, unless you design your setup to somehow exhaust the ozone to the outdoors, you really don’t want the 185nm line. Ozone is very bad for your body. It’s considered an air pollutant.

 

By the way the alternative link can’t be seen from the US either. It is probably illegal here because of the risk to the environment from the mercury.

[Fandyus]

I see, thank you guys for all the info!

[dabateman]

It looks like they are coming down in price again.

Fandyus, that image looks like a legitimate 3W E17 base UVC lamp. You need a special ballast to run them. If you use a E26/E27 (standard house fixture) to E17 adapter, they will explode. I blew up 3 that way.

The ballast can be expensive and best to buy with the bulb. They can be run off DC (a battery) or with AC (plugged in to an outlet).

 

I think I have one that should output 185nm. But at only 3W, they are dim.

 

The ideal use case was to screw into an appliance fixture inside an oven to "sterilize it". This will not sterilize it and its not possible as most in the USA run 120V not 11V and the bulb will explode.

[Fandyus]

It looks like they are coming down in price again.

Fandyus, that image looks like a legitimate 3W E17 base UVC lamp. You need a special ballast to run them. If you use a E26/E27 (standard house fixture) to E17 adapter, they will explode. I blew up 3 that way.

The ballast can be expensive and best to buy with the bulb. They can be run off DC (a battery) or with AC (plugged in to an outlet).

 

I think I have one that should output 185nm. But at only 3W, they are dim.

 

The ideal use case was to screw into an appliance fixture inside an oven to "sterilize it". This will not sterilize it and its not possible as most in the USA run 120V not 11V and the bulb will explode.

Thanks for the tips but as I said, I'm not getting it. My camera can't see UVC and I don't have any suitable protective gear, or a suitable space to run such "angry" light sources.

[Andrea B.]

You know in the past I have considered "banning" UVC here because I worry about the danger. But the only sensible thing to do is to treat everyone as adults and request that anybody messing around with UVC take strong precautions because some UVC wavelengths are extremely harmful and some are not so much. But you cannot know what kind of UVC illumination you might encounter if you buy off the 'Bay.

 

And I also ask anyone discussing UVC to create and post a little warning phrase about the dangers of UVC at the beginning of their topic. (Not in every post. Just at the begining of a topic.) David/dabateman had one once. Hey, where is it? Maybe you could post it for others to use??

 

Thanks, all!!!

 

UVC = Bad JuJu. Many potatoes rolled away......

^{No, don't use that as a warning. I was just riffing.}

[Stefano]

Here there's one: https://www.ultravioletphotography.com/content/index.php/topic/3672-last-and-final-185nm-attempt

 

And another: https://www.ultravioletphotography.com/content/index.php/topic/3585-uvc-uvb-uva-monochrom-acorn-series

[OlDoinyo]

.. It is probably illegal here because of the risk to the environment from the mercury.

 

Yet it is quite legal to sell fluorescent tubes and other mercury-containing devices. I don't think the US authorities would go so far as to censor mention of such a device on the internet. Perhaps the seller might want the product displayed only in markets to which they can ship, however.

[Andrea B.]

Stefano, thanks for finding David's warning info. I'm going to extract it and pin a warning.