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mogur
regnartS

Registered: 11/15/05
Posts: 322
Loc: Puget Sound
Last seen: 11 years, 2 months
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EPROM eraser- UV germicidal
#5367466 - 03/05/06 01:48 PM (17 years, 10 months ago) |
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I was erasing some EPROMs with my UV eraser, and happened to notice the bulb said germicidal right on the glass, so I looked up some info on the internet. If you don't want to go blind, skip to the last paragraph of this post.
Quote:
From this link-
The germicidal spectrum of the ultraviolet wavelength is from 2000 to 3000 Angstroms, with the peak of 2537 Angstroms. The total UV energy emitted from all sides of the UV lamp is expressed in watts. The total exposure of the liquid is expressed in microwatt-seconds per square centimeter, which is a product of energy, time, and area. The same number of micro-watt seconds per square centimeter can be accomplished with a short exposure at a high intensity of UV or a long exposure at a low intensity of UV.
All known micro-organisms are destroyed with proper exposure to ultra-violet radiation in the 2,000 to 3,000 Angstrom Unit range. Most water-borne pathogenic (disease-causing) Micro-organisms are destroyed with under 10,000 Microwatt seconds per square centimeter.
Ultraviolet Energy Levels at 2537 Angstrom Units Wavelength required for 99.9% Destruction of Various Microorganisms. UV Energy in Microwatt- seconds per Square Centimeter
Bacteria- Bacillus anthracis 8700 Bacillus megaterium (vegetative) 2500 Bacillus megaterium (spores) 52000 Bacillus subtilis (vegetative) 11000 Bacillus subtilis (spores) 58000 Clostridium tetani 22000 Salmonelia enteritidis 7600 Salmonelia typhosa (typhoid) 6000 Staphylococcus epidermidis 5800 Streptococcus iactis 8800
Mold Spores- Aspergillus glaucus 88000 Aspergillus niger 330000 Penicillum expensum 22000 Rhizopus nigricans 220000
Algae- Chlorelia vulgaris 22000
Protozoa- Nematode eggs 92000 Paramecium 200000
Viruses- E. coli 6600 Hepatitis virus 8000 Influenza virus 6600 Tobacco masaic virus 440000
Yeast- Baker's yeast 8800 Brewer's yeast 6600 Common yeast cake 13200 Saccharomyces sp. 17600
The output of my G6T5 bulb is 1.7 watts. This computes to at least 1000 uW/cm2 at 4 inches, the furthest point of the jar from the bulb. This includes loss from travel through air, through the glass (or PETE plastic) and through the liquid with an assumed coefficient of UV absorption of .15 (most tap water is about .05). Eight hours (overnight) is almost 30,000 seconds, or a total of 30 million uW-secs/cm2, which should be enough to purify the pope.
I'm not saying that this is a replacement for a PC, or that anyone should run out an buy a UV lamp (the bulb sells for about ten bucks). I happened to have one, so I'm using it in conjunction with other aseptic methods. It does little beyond the surface of any material that isn't fairly transparent and free of visible particles. But it can help with ensuring sterility of liquid cultures. Of course, if you skipped the technical details above, don't UV the culture after noc'ing, it is a fungicidal agent, and will kill mushroom spores and mycelia. Can also help battle the bugs on surfaces and in the air, as UV lamps are frequently incorporated in flow hoods for that purpose. I know that this is all old news to most of you, just thought I would mention it in case some happen to have an EPROM eraser hanging around.
Btw (by the way), black lights are UV, but the wrong spectrum. You need UV-c output.
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agar
old hand


Registered: 11/21/04
Posts: 9,056
Loc: Somewhere Else
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Re: EPROM eraser- UV germicidal [Re: mogur]
#5367542 - 03/05/06 02:13 PM (17 years, 10 months ago) |
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In another life, when I had a positive pressure quasi/clean room.
I installed a UV bulb in the sheet-metal duct work running from the hepa filter into the room.
I worked out WELL.
However, unless shielded (100%), they are dangerous puppies to play with. As they cause skin cancer and/or blindness with exposure.
Currently, I use a shielded turbo twist UV sterilizer (for up/scale aquarium water filtration)to decontaminate water.
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Delinquentes
TIMMMAYYYYYYY


Registered: 02/07/06
Posts: 543
Loc: Hidin' in a bowl of rice
Last seen: 3 months, 16 days
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Re: EPROM eraser- UV germicidal [Re: agar]
#5367566 - 03/05/06 02:22 PM (17 years, 10 months ago) |
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UV light is another way to create ozone. There are plans for a UV ozone generator evailable, but the precautions involved are a lot more stringent. UV light is commonly used to treat water in spas and whirlpools.
The plan I saw used the inner bulb of an HID fixture. Once the outer bulb is broken, the inner bulb puts out MEGA UV rays.
-------------------- "The price of meat has just gone up, and your old lady has just gone down!" ~~ Zappa Click Here for a ghetto ozone generator Tek. Want to learn more about ozone as a bacteria killer? Click Here
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mogur
regnartS

Registered: 11/15/05
Posts: 322
Loc: Puget Sound
Last seen: 11 years, 2 months
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Re: EPROM eraser- UV germicidal [Re: agar]
#5367575 - 03/05/06 02:25 PM (17 years, 10 months ago) |
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Damn, forgot about the exposure warnings. Thanks, agar.
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mogur
regnartS

Registered: 11/15/05
Posts: 322
Loc: Puget Sound
Last seen: 11 years, 2 months
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Re: EPROM eraser- UV germicidal [Re: Delinquentes]
#5367629 - 03/05/06 02:46 PM (17 years, 10 months ago) |
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Yeah, there are special bulbs at 185 angstroms in wavelength meant to create ozone, but as you probably know, it only creates about 1/10 the ozone that your ozone corona discharge tek will create with the same energy input. Any disinfecting agent, chemical or otherwise is dangerous to humans without proper understanding of safe handling procedures. Even a PC can create an unwanted tunnel through your head. A little fear can sometimes be prudent.
EDIT: Make that 1850 angstroms, my head is only remotely connected to my fingers. Or, 185 nm.
Edited by mogur (03/05/06 03:04 PM)
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Delinquentes
TIMMMAYYYYYYY


Registered: 02/07/06
Posts: 543
Loc: Hidin' in a bowl of rice
Last seen: 3 months, 16 days
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Re: EPROM eraser- UV germicidal [Re: mogur]
#5367638 - 03/05/06 02:49 PM (17 years, 10 months ago) |
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This is true...plus the corona discharge is SOOOOO cool to watch while you are under the influence. A darkened room and a couple of shrooms and it would be a party
-------------------- "The price of meat has just gone up, and your old lady has just gone down!" ~~ Zappa Click Here for a ghetto ozone generator Tek. Want to learn more about ozone as a bacteria killer? Click Here
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cappa
Nerd
Registered: 02/12/06
Posts: 854
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Re: EPROM eraser- UV germicidal [Re: Delinquentes]
#5368285 - 03/05/06 06:51 PM (17 years, 10 months ago) |
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Very informative, thank you, I will be looking into it.
~Cappa.
-------------------- Their are 10 types of people. Those that understand binary, and those who don't. ~Cappa.
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DrAbominable
derp

Registered: 01/18/06
Posts: 155
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Re: EPROM eraser- UV germicidal [Re: cappa]
#5514621 - 04/14/06 01:31 AM (17 years, 9 months ago) |
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They are efficient, but be careful. Thought about putting one inside a flow hood before. On the inside , between the exhaust of the fan and the filter as an extra measure of sterility! The light being encased with in the unit would eliminate exposure correct? Any body have any insight?
Peace......  Maybe I should have Finished reading before I posted!
-------------------- lolwut
Edited by DrAbominable (04/14/06 01:35 AM)
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