# UVC Sanitizer Box - mostly fake



## PhotonWrangler (Apr 17, 2021)

I bought a couple of "UVC Sanitizer Box" devices recently out of curiosity to see if the LEDs might be useful for other projects. This is a white plastic tub with a door that's marketed as something for sanitizing your cellphone, keys or other small objects. Put your phone inside, close the door and push the button to "sanitize" it in 5 minutes.

The photos on the carton show an array of bluish LEDs running along both sides of the tub and imply that the device bathes your cellphone in UVC light.

Upon close inspection I found that all of the LEDs look the same except for one larger metal encased one on the left side. The others are smaller ones with white plastic cases. Hmm.

I unboxed a second unit and found the same thing. This wasn't a manufacturing fluke; they intended to have one LED that's somehow different from the rest of them. Could it be that only one of the LEDs is actually UVC and the rest are fake?

It turns out that this is indeed the case. I used a UVC-detecting phosphor indicator and confirmed that this sanitizer contains exactly ONE actual UVC LED, and the rest are regular blue LEDs whose wavelength was carefully chosen to resemble the same visible color that's emitted by the actual UVC LED. This means that if you put your cellphone in thiis unit, it will only sanitize the upper left corner of the phone! The rest is just Covid sanitization theater.

I wanted to give everyone a heads-up on this so you don't wind up fake-sanitizing your phones or other devicves. The SKU on the bottom of the carton is 7498603211,, Item # 03211 from TV Direct LLC, sold in the DIY chain that rhymes with petards for around $10.


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## Blades (Apr 17, 2021)

Good to know, thank you.


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## KITROBASKIN (Apr 17, 2021)

From wikipedia:

"*Hoist with his own petard*" is a phrase from a speech in William Shakespeare's play Hamlet that has become proverbial. The phrase's meaning is literally that a bomb-maker is blown up ("*hoist*" off the ground) by *his own* bomb (a "*petard*" is a small explosive device), and indicates an ironic reversal, or poetic justice.


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## PhotonWrangler (Apr 17, 2021)

Thanks Kitrobaskin. I couldn't think of another two syllable word that rhymed as well. No hidden meaning intended for the store chain!

**Edit** 
Ok, it also rhymes with Bernard's. I'll use this going forward.


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## KITROBASKIN (Apr 19, 2021)

PW, your posts are always appreciated. 
Having heard the 'hoist petard' phrase in the past, I thought petard might be trousers or underwear or something. 

Would you consider that the inside of these sanitizer boxes might somehow reflect the UVC emissions, thereby exposing more of the object to the waves?


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## PhotonWrangler (Apr 19, 2021)

Thank you for your kind words, Kitrobaskin.

The inside of the box is white plastic. I will conduct an experiment to look at reflections and post my findings here.


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## Dave_H (Apr 20, 2021)

PhotonWrangler said:


> I bought a couple of "UVC Sanitizer Box" devices recently out of curiosity to see if the LEDs might be useful for other projects. This is a white plastic tub with a door that's marketed as something for sanitizing your cellphone, keys or other small objects. Put your phone inside, close the door and push the button to "sanitize" it in 5 minutes.
> 
> The photos on the carton show an array of bluish LEDs running along both sides of the tub and imply that the device bathes your cellphone in UVC light.
> 
> Upon close inspection I found that all of the LEDs look the same except for one larger metal encased one on the left side. The others are smaller ones with white plastic cases. Hmm.



Good piece of detective work...thanks. I noticed these products in a number of stores generally in the range of $25-$40 or more but was suspicious by the lack of meaningful specs on the packaging, and some dubious claims.

Based on reading about UV-C LEDs they have very low efficiency for a number of reasons, no doubt cost a lot more than regular visible LEDs, and not likely to find a whole bunch of them in a low-cost consumer product.

BTW which phosphor(s) work for UV-C versus near-UV? I imagine some specific minerals would work, if you have them.

Digressing a bit, there are line-powered LED near-UV bulbs out there claiming germicidal properties but rather vague on that, and not claiming COVID specifically, which we know near-UV is not good for. One is even "dual-mode" with regular visible light, with one vague warning about eye exposure. Lots of opportunistic products to be wary of.

Dave


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## badtziscool (Apr 20, 2021)

I'm pretty sure we all had the feeling this was the case. Nonetheless, thank you for confirming our suspicions PhotonWrangler.


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## PhotonWrangler (Apr 24, 2021)

Update - 

It looks like the single UVC LED is a dual wavelength UVC/UVA unit with two separate emitters in it, one for UVC and the other for UVA. The other LEDs in the unit appear to be just UVA, which can kill some bacteria but cannot deactivate Covid or other viruses. I have not identified the UVA part yet.

The UVC led appears to be a "3535 UVC UVA" part. The link includes a photo of the sanitizer box in question.
[h=1][/h].


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## snakebite (Jul 13, 2021)

however the safe and healthy uvc wand does emit plenty of uvc.
it will erase eproms in 2 power cycles.
roughly the same time my g15t8 takes to consistently pass a blank check.


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## PhotonWrangler (Jul 14, 2021)

Erasing eproms... gosh that takes me back. I used to use a g15T8 tube to wipe eproms in about 20 minutes. That was before they had the improved glass bulbs that blocked the ozone-generating wavelength.


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## Dave_H (Dec 28, 2021)

I've just picked up a wand-style UV LED disinfectant device cheap at a second-hand store. It parallels description of the box-style earlier described: 18 of 20 SMT LEDs have white body and appear to give off near-UV. Two have gold-tinted bodies, hard to tell how much far-UV they put out but not much; these have distinctly purple (v. violet) visible glow.

Product brand is Medic Therapeutics.

Unit seems to work but not useful to me for disinfection. It uses 18650 with USB charger and makes my day-glo posters light up, not brightly, but OK for about $4.

Dave


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## PhotonWrangler (Dec 28, 2021)

Dave_H said:


> I've just picked up a wand-style UV LED disinfectant device cheap at a second-hand store. It parallels description of the box-style earlier described: 18 of 20 SMT LEDs have white body and appear to give off near-UV. Two have gold-tinted bodies, hard to tell how much far-UV they put out but not much; these have distinctly purple (v. violet) visible glow.
> 
> Product brand is Medic Therapeutics.
> 
> ...


The ones with gold bodies could be UVC. See if they can fluoresce some postage stamps, which might contai n UVC activated phosphors.

The white-bodies UVA or near-UVA leds might be able to kill certain types of bacteria but not viruses, so it's not an entire loss in terms of "sterilizing," however in the current context most are looking for devices that can kill (deactivate) viruses.


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## Dave_H (Dec 30, 2021)

PhotonWrangler said:


> The ones with gold bodies could be UVC. See if they can fluoresce some postage stamps, which might contai n UVC activated phosphors.
> 
> The white-bodies UVA or near-UVA leds might be able to kill certain types of bacteria but not viruses, so it's not an entire loss in terms of "sterilizing," however in the current context most are looking for devices that can kill (deactivate) viruses.


 Good on both points. Gold SMT LEDs resemble dual UVA/C 3535 part by Dongguan Uchi Elec. "35UVA+UVC06-003" but can't be sure.

"Stamp test" seems less conclusive. Patterns on current Canadian stamps are not visible under normal light but show up dimly with UVA flashlight and this wand light. Under strong UVC (mercury tube w/filter), patterns are visible, also border lights up yellow-green. UVC from LEDs must be fairly weak but wand having been used may have some impact. List price of the wand is US$75 plus taxes and shipping.

Dave


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## PhotonWrangler (Dec 31, 2021)

Back in the days of air mail stamps, the USPS used a UVC reactive phosphor coating on these stamps and a different coating on regular surface mail stamps so the sorting machines could differentiate them and route them accordingly. I believe that the continued use of UVC reactive phosphors is probably mostly an anti counterfeiting measure now. They're still handy for detectming the presence of UVC.


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## Dave_H (Feb 17, 2022)

I recently spotted a small handheld UV LED "disinfection" light in a Canadian chain store for only $10. Part of me thinks that if/when feeling like buying one, I should lie down until the feeling goes away. OTOH, perhaps they will go on sale for half-price, happens fairly often with this store. At least it might be a good UVA-mostly light.

In the same store I saw a very small tube-type UVC light running on 4AA. Cost was $13 but was the last one and didn't bite, interesting though.

Dave


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## PhotonWrangler (Feb 17, 2022)

This one is the real deal. I picked it up for $50 at the DIY chain that rhymes with Bernards and confirmed the UVC output with my phosphor detector card.


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## Dave_H (Mar 8, 2022)

PhotonWrangler said:


> This one is the real deal. I picked it up for $50 at the DIY chain that rhymes with Bernards and confirmed the UVC output with my phosphor detector card.


The small handheld sanitizer wand at the store which rhymes with "petards" or "Bernards" looks similar to the one I picked up which uses a UVC tube (by appearance of the image). SKU #3460672.

Dave


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## PhotonWrangler (Mar 8, 2022)

I bought one of those UVC tube-based sanitizers at the "M" store and it was DOA. I just set it aside for now. One of these days I'll try to isolate whether it's the HV power supply or the tube. This is why I'm happy to see progress on UVC LED development.


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## Dave_H (Mar 9, 2022)

PhotonWrangler said:


> I bought one of those UVC tube-based sanitizers at the "M" store and it was DOA. I just set it aside for now. One of these days I'll try to isolate whether it's the HV power supply or the tube. This is why I'm happy to see progress on UVC LED development.


I've already had mine apart to look at the HV supply, small power transformer; no measurements though.

Mine does not operate unless pointed downwards, at first thought it was NF, could that be your problem?

Dave


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## alpg88 (Mar 9, 2022)

at the begining of covid i bought 3 8w uvc fluorescent lights, installed 2 in my bathroom. i turn them on for about 15 min, after that the whole bathroom smells like chlorine, it does make plenty of ozone, which is a good thing. We no longer disinfect clothes, but i run that thing daily anyway. it removes all smell of poop from cat's litter box. however it has no effect on urine smell. guess it is not caused by bacteria, so UV cannot kill it.


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## Dave_H (Mar 9, 2022)

Exposure to ozone can be a health hazard...be careful!

Dave


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## PhotonWrangler (Mar 9, 2022)

I tried it at all angles with no response so I don't think it's the tip switch. Good thought though!


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## Dave_H (Jul 7, 2022)

I recently acquired a Globe brand UVC disinfectant box model 60057 obviously on surplus/clearance as the price was $10 (on sale for $5).

Inside are four square gold-coloured SMT LEDs (280nm), only on with box lid closed. I found the interlock is magnetic, easily fooled. It runs from USB (2W max.) and uses a 15-minute timer. Other than that, no technical info.

It lights up some of my day-glo posters and other fluorescent material.

I bought it not for its original purpose, but with COVID surging once again who knows (except experience suggests most transmission via "aerosol" versus solid surfaces).

Dave


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## fulee9999 (Jul 7, 2022)

To avoid this issue ( being sold a blue LED instead of UVC ) I actually made my own small sanitizer







You can buy these 3,5mW 275nm UVC LED modules and you can daisychain them, so the whole assembly runs off of one USB-C connector.
One module was around $10, so this is a $50 contraption, but tested with an UVC dosimeter this actually works.

Whenever you buy something that is claimed to be UVC:
1, Make sure it actually emits any UVC at all, you only need a cheap tester card for that, like so:





2, Check the dose it emits, you will need a dosimeter card for that, like this one:
( this is what some hospitals in the US tend to use )


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## alpg88 (Jul 7, 2022)

Dave_H said:


> Exposure to ozone can be a health hazard...be careful!
> 
> Dave


Yes it can be if you get exposed to high concentration for certain amount of time, but it also has many benefits.


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## PhotonWrangler (Jul 7, 2022)

alpg88 said:


> Yes it can be if you get exposed to high concentration for certain amount of time, but it also has many benefits.


I don't think UVC LEDs will generate ozone. IIRC the mercury vapor line that produced ozone was in the ~180nm range.


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## alpg88 (Jul 8, 2022)

PhotonWrangler said:


> I don't think UVC LEDs will generate ozone. IIRC the mercury vapor line that produced ozone was in the ~180nm range.


They should if they are of proper bandwidth, oxygen does not care if it is a led produces uvc or a fluorescent bulb. problem is all those fake uv sterilizer boxes do not have such leds, and even if some do their power is way to small to make any measurable amount. those leds make milliwatts.
I use fluorescent bulbs 2x 8w, i get plenty of ozone, it would be extremely expensive to make 16w with true uvc leds.


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## PhotonWrangler (Jul 8, 2022)

alpg88 said:


> They should if they are of proper bandwidth, oxygen does not care if it is a led produces uvc or a fluorescent bulb. problem is all those fake uv sterilizer boxes do not have such leds, and even if some do their power is way to small to make any measurable amount. those leds make milliwatts.
> I use fluorescent bulbs 2x 8w, i get plenty of ozone, it would be extremely expensive to make 16w with true uvc leds.


Back in the 80s or 90s they revised the formula for the glass envelope on fluorescent germicidal lamps to cut off the shorter wavelengths and thus cut back on ozone production. I've had both types of 8w tubes and the newer ones are much less stinky. Wavelengths longer than 240nm won't react with oxygen to produce ozone. I haven't seen any UVC LEDs that produce spectra shorter than 255nm yet. That doesn't mean it won't happen someday though.


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## Dave_H (Jul 14, 2022)

I've found yet another (locally) heavily-discounted Globe-brand LED "disinfection" light #26180, which combines regular white LEDs in a USB-rechargeable 14" light strip, with some UVA/UVC LEDs and motion detector. 

I think I payed less than $10. Still seeing regular price US$59 and up, not worth that much in my opinion.

Besides visible SMT LEDs, inside are eight LEDs which appear to be UVA, and one gold square LED which is likely UVC (they state 352nm and 280nm respectively). UVA is barely mentioned on package.

It's designed to do a disinfect cycle but shut UV off when motion is detected. Interesting feature but not sure how well it works in reality, and no plans to use it for this. So while the claims are not exactly untrue, it seems to create confusion as to how useful it is for COVID (on most peoples' minds).

Dave


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## PhotonWrangler (Jul 14, 2022)

Dave_H said:


> I've found yet another (locally) heavily-discounted Globe-brand LED "disinfection" light #26180, which combines regular white LEDs in a USB-rechargeable 14" light strip, with some UVA/UVC LEDs and motion detector.
> 
> I think I payed less than $10. Still seeing regular price US$59 and up, not worth that much in my opinion.
> 
> ...


Interesting. This sounds similar to a "Honeycomb" UVC puck light that I picked up from the chain that rhymes with Bernard's. It contains one visible white LED and two gold UVC LEDs driven by a motion sensor. It's meant to mount under a cabinet or inside a medicine cabinet. When it see motion, the white LED turns on for around 30 seconds, then it turns off and the UVC LEDs turn on for 30-60 seconds or so. I thionk I paid $25 for it (regular price at the time).


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