UV LED's for sterilization???

[travelinman]

I'm sorry, it just doesn't work that way. Stop shining that UV LED into your pants, and get a real vasectomy like the rest of us...

That's why I keep getting a real bad sunburn down there! :thinking:

 

[travelinman]

Steripens are a great way to get sick. They only work in water. If you dip your drinking vessel into the contaminated water source, then use the steripen, what is going to purify the germs you got on the outside and top of the container? You will just recontaminate trying to pour across the top of the container to put it into another container to drink it.

The military tabs tell you to loosen the lid and shake the canteen to get antiseptic water onto the threads. The steripen purified water is not antiseptic so it would not kill anything by itself. The chemicals in the military tabs do actively kill bugs.

Also, sterilized crap is still crap. The solids in the water actually will protect germs inside the solids. Light can't get to it so it lives through the treatment and goes into your belly.

Use a real water filter.

I love my Steri pen, got two of them in fact. I used it all over S. America last year and didn't get the runs at all. I also didn't eat salads, or any fruits that I couldn't peel myself. You can also get bacteria from any food that you buy at a stand or restaurant so it's really hard to tell where you pick it up if you travel in any poorer part of the world.

Steri pens work great though, if you are careful, but if you use the poison pills I wouldn't trust what the "poisons" do to you after they kill the bacteria.

 

[batmanacw]

I love my Steri pen, got two of them in fact. I used it all over S. America last year and didn't get the runs at all. I also didn't eat salads, or any fruits that I couldn't peel myself. You can also get bacteria from any food that you buy at a stand or restaurant so it's really hard to tell where you pick it up if you travel in any poorer part of the world.

Steri pens work great though, if you are careful, but if you use the poison pills I wouldn't trust what the "poisons" do to you after they kill the bacteria.

Did you use them in the field or just in a hotel? Too totally different situations. I would not hesitate to use one in my hotel room, but try dunking a glass in a river and not getting any bad stuff on the outside of the glass where you put your lips.

I also tend to avoid eating anything not really well cooked when traveling in Mexico. That is when I can't avoid it totally.

Those poisons taste terrible. that is why I use a katadyn hiker pro. The water from our local streams taste better than bottled after I am done. I am going to pick up a pocket filter by the same company in the near future.

I travel for a living. A sweetwater filter, straw type filter, and micropur tablets come with me every time I travel anywhere.

 

[turbodog]

Steripens are a great way to get sick. They only work in water. If you dip your drinking vessel into the contaminated water source, then use the steripen, what is going to purify the germs you got on the outside and top of the container? You will just recontaminate trying to pour across the top of the container to put it into another container to drink it.

The military tabs tell you to loosen the lid and shake the canteen to get antiseptic water onto the threads. The steripen purified water is not antiseptic so it would not kill anything by itself. The chemicals in the military tabs do actively kill bugs.

Also, sterilized crap is still crap. The solids in the water actually will protect germs inside the solids. Light can't get to it so it lives through the treatment and goes into your belly.

Use a real water filter.

Except filters do not get viruses....

I've got something nobody has mentioned, a uv aquastar
http://www.uvaquastar.com/skins/2008Style/standard2.aspx?elid=201&plk=69&SkipFlip=201

Fits to a normal 1l nalgene bottle. Had it for about 4 years now. Comes with a little set of prefilters (like a coffee filter) to screen out big chunks.

 

[turbodog]

For those reading this in a 'here's some good water filtering/etc advice':

Chemicals such as chlorine and iodine can leave a nasty taste. They also have a dwell (wait) time that can be short (in warm water) or 4 hours or more (in cold water). They also DO NOT GET cryptosporidium.

Filters can let viruses such as cryptosporidium through.

UV kills all nasty bugs if the water is clear enough. Keep the threads of the bottle clean and fitler out the chunky stuff and you'll be fine.

MSR makes a device which delivers some sort of mystery liquid (paraphrasing their words) based on salt water breakdown through electric current. It's supposedly effective against bacteria AND viruses. It suffers from dwell time, but taste is not affected much.

Boiling vigorously for 5-10 minutes kills everything.

Contaminants are somewhat removed by filtering as filters often contain charcoal 2nd stage filters which help with taste issues.

Personally, when in the backcountry, I filter then dose with UV. My msr filter screws on to top of the uv aquastar bottle. Filter comes off, uv goes in, and I am ready to go.

So that's it. Not going to derail thread anymore. Questions? PM me.

 

[MountainVoyageur]

It is now almost a year since the last post -- any update on when we might see SteriPEN products using UV LEDs?

:twothumbs

 

[PhotonWrangler]

I still don't see any major movement in the shortwave UV LED arena. I'd like to have an LED-based SteriPEN also, but there are apparently some serious manufacturing challenges. For now I'm sticking with conventional mercury-vapor UVC lamps.

**EDIT**

Maybe I should post this one under Pet Peeves, but I'm seeing some 365nm longwave UVA LEDs being marketed as "UVC" (shortwave germicidal) LEDs. Buyer beware.

UVA = 400-320nm longwave "blacklight"
UVB = 320-290nm medium wave
UVC = 290-100nm "germicidal" shortwave

 

[Wangstang]

Another year down...any updates?

Wes

 

[PhotonWrangler]

I still haven't seen any breakthroughs in shortwave UV LEDs. We're still stuck with germicidal fluorescent lamps for awhile longer.

 

[slebans]

I still haven't seen any breakthroughs in shortwave UV LEDs. We're still stuck with germicidal fluorescent lamps for awhile longer.

I keep updating a folder whenever I come across anything to do with UV LEDs and disinfection. The latest entry I have is:
http://www.crystal-is.com/press.cfm/newsitem/86372

Some day, I want to have a LED based sterilization room for the daily disinfection of metal greenhouse production carts.

Stephen Lebans

Stephen Lebans

 

[PhotonWrangler]

Interesting - thanks Stephen.

 

[slebans]

Another "breakthrough" but still only half the WPE of the current non LED solutions.

http://www.s-et.com/news.html
[h=6]SETi reaches milestone UVC LED efficiencies of over 10%[/h]Sensor Electronic Technology, Inc (SETi) announced record efficiencies of ultraviolet light emitting diodes (UV LEDs) operating in the germicidal UV-C range of 11% external quantum efficiency (EQE) with a corresponding wall-plug efficiency (WPE) of 8%. This industry beating result was achieved under the DARPA Compact Mid-Ultraviolet Technology (CMUVT) program and in collaboration with Army Research Laboratories (ARL). read more (pdf)

 

[PhotonWrangler]

Another interesting find. Thanks Slebans.

Even with a WPE that is half of fluorescent-based counterparts, I think there will be a number of applications where this is the preferred solution just from the standpoint of ruggedness. I've never liked the idea of carrying around a fragile glass tube when I need a portable UV source.

 

[eseemann]

I know they work but I guess since I can not see the magic smoke I harbor some caveman type fear of it. Same with the water purification tablets. I would use them in a pinch but if I have time I think I will still boil.
Thing the lights are really good for is going to some place like Mexico with a less then 100% water supply. Many an american has fallen before the might of the single cell.

 

[Inkidu]

The pdf link didn't work for me for the 278nm uv led so I thought I would post it again.
Anyone know the usual length between a press release and the actual availability for this company.

Might be a DARPA hard problem.

Any help would be appreciated.

 

[slebans]

Another breakthrough to keep an eye on.
http://www.hexatechinc.com/news_events.html#aug072012

 

[slebans]

http://www.ledinside.com/news/2013/1/japan_deep_ultraviolet_led_20120122

Japanese researchers Akinori Koukitu and Yoshinao Kumagai, who are professor and associate professor, respectively, at the Division of Applied Chemistry, the Tokyo University of Agriculture and Technology (TUAT), and researchers of Tokuyama Corp. , have made breakthroughs on a deep ultraviolet LED that has the world's highest levels of output characteristics.

With a forward current of 150mA, its output and external quantum efficiency are 20mW and 3.0%, respectively.

 

[JohnR66]

Nichia has some high power deep UV LEDs:
http://www.nichia.co.jp/en/about_nichia/2012/2012_122601.html

 

[PhotonWrangler]

Nichia has some high power deep UV LEDs:
http://www.nichia.co.jp/en/about_nichia/2012/2012_122601.html

Wow. I'll bet those will cost a pretty penny.

 

[The Electrician]

I just found this forum with a search for UV flashlights. I'm interested in finding fluorescent minerals, some of which require short wave UV. In the past I've used a mercury lamp with a filter to pass the 254 nm radiation, but I've been wondering if LED technology has progressed to the point where a short wave (deep) UV LED flashlight would be possible for a reasonable price.

I see the Nichia LEDs linked a couple of posts up, and the power level is amazing, and more than needed for my purpose.

So far, I've been a little OT, but LEDs suitable for short wave mineralogy are also good for sterilization. Here's a link to a source of LED sterilization items I found. The radiant power of these LEDs is much lower than the Nichias, but the price is probably also lower. This is the US web site for a Chinese supplier:

http://www.ledwv.com/en/uv-sterilizer-c-21.html

It looks like you could actually buy these and not have to try to get a sample, although for the LEDs a minimum order quantity of 20 is required.