Does any1 own a UV dropin?

Such as this:

I'm interested if it does work good on blood not just urine.


I have one or two. Couldn't say about blood though, never tried. The usual advice is to use a blue LED for following blood trails so a UV LED might, or might not work. Trying to think of anything bloodstained around here I could test it on. I imagine this is for hunting use so it will be fresh rather than dried blood?

From a quick Google you want 250-300nm and a lot of power (as in wear eye protection) to get dried bloodstains to fluoresce properly. I don't think any LED can produce light of that short a wavelength, AFAIK the shortest wavelength LEDs are more than 350nm.

However, I can say that that dropin will show just how eventful a life a mattress has had. Having checked the mattress in a friend's rented place, we took it outside and burned it.

I have a 501B with the UV drop-in DX sells... somewhere. I haven't really played with it in ages but whether you can see body fluids depends almost entirely on the wavelength of the light emitted. The lights DX sells are supposed to be around 400nm and even the visible light is rather bright (as an aside, it's a good idea to err on the side of caution when playing with UV, even if the light emitted is supposedly within "safe" ranges). According to Wikipedia, the wavelengths used for forensic purposes are between 250 and 300nm and I recall reading somewhere that the sweet spot is supposed to be around 260nm for body fluids. Since the "glow" (think CSI & Luminol) you see is due to the reaction of amino acids with the UV light, I'd guess that it comes down to wavelength plus how degraded the blood is (as bacteria break down the amino acids, there should be less of an reaction).

Edit: I'm a bit late. Sorry. ;)

Thanks to both. Off to reading, and searching for the correct wavelenght IR emitter of some type.

I grabbed that one one, if turns out not suitable for blood i might at least have the "pleasure" to find where that furry fat-cat of mine did his thing on rare occasions. works on dried body fluid too?

Certainly does! Never use it to check a hotel mattress unless you enjoy sleeping on the floor.

Lol i'll keep that in mind. :) Oh and yes, hunters wanted one to play with. Not for CSI series fetishists.

They actually make small germicidal UVGI wands these days that look pretty much like a blacklight from the 70s.

I always wondered if those actually do anything because I know that the medial UVGI stuff is either almost entirely automated or specifically requires a "operator-presence" device (fancy name for a safety switch located well away from any harmful rays and gases) to be in compliance. And, well, there's a very good reason for that because that kind of equipment will not just kill germs - mess with it long enough, and it will kill you. That's why I'd expect the stuff they sell at Walmart to be far less powerful and thus far less effective.

*filing this one under ignorance is bliss* ;)

Certainly don't use them in the hospital I work in.

Heavily contaminated stuff ends up in a place about 30 miles away. And most of it ends up being burned at very high temperatures.

I am not even sure what they use the UVGI stuff at my wife's place of work for. You need a separate access card to go there (not because someone is going to walk out with a machine weighing a dozen metric tons with its own separate air treatment/control/power systems but rather because the insurance company requires it) and they don't allow visitors so I've never been there. As I understand it, it's basically an airport x-ray machine on steroids. ;)

Germicidal UV stuff is essentially soft X-Rays. I'd definitely want access and operator controls.

There was a guy at Edinburgh University in the late 70's called Dr. Charlie Beevors. He'd got into X-Ray crystallography in the late 1930's and had worked with his hands in the beams from a ludicrously powerful machine. The wall at the end of each beam line was charred. I'll never forget him saying that X-Ray burns are nasty as they burn from the bone out. He didn't have fingers any more, but ten tumours instead. High energy radiation is best not messed with.

One cannot beleive how much can be learnt on a flashlight forum. :) Thanks for sharing.