Working with UV-C on independent project

AI Thread Summary
UV-C light from a low-pressure mercury lamp penetrates various materials, with reports indicating it can pass through plastics, raising concerns about protective eyewear effectiveness. The discussion highlights the importance of understanding UV-C exposure, noting that even brief exposure may be less harmful than that from arc welding. The project aims to isolate and expand bacteria with natural UV-C resistance, inspired by the resilient bacterium D. Radiodurans. It is emphasized that the culture will not adapt but rather select for existing resistant strains. This research could yield valuable insights into bacterial resistance mechanisms.
Super Monkey
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Hello,
I'm using UV-C (Hg low pressure lamp) and I wanted to see if someone could give me some insight.

I have a couple of questions:

1) How far does UV-C penetrate through various materials? In my testing, it seems to go straight through plastics. I have UV blocking glasses - but those are most likely designed for UV-A/B. Some literature I found indicates that any eyeglasses should be more than adequate for stopping all UV-C - but I'm nervous because it seems to have no problem with plastics (not sure the type)

2) What effects of UV-C could I expect to feel on myself? I would only be exposed a few seconds at a time - I imagine that this is much less radiation than I would be exposed while arc welding (used to do that a lot). The bulb I am using is a Ushio G25T8 25 Watt bulb. I can't imagine that this UV source is more dangerous than a 130 ampere arc...

Anyways, I'm working on a biology project to see if I can encourage a culture of bacteria to adapt a resistance to UV-C with the hopes of earning a scholarship or something along those lines. Any help would be great - even if you just point me in the direction of a book!

Thanks.
 
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Super Monkey said:
Hello,
I'm using UV-C (Hg low pressure lamp) and I wanted to see if someone could give me some insight.

I have a couple of questions:

1) How far does UV-C penetrate through various materials? In my testing, it seems to go straight through plastics. I have UV blocking glasses - but those are most likely designed for UV-A/B. Some literature I found indicates that any eyeglasses should be more than adequate for stopping all UV-C - but I'm nervous because it seems to have no problem with plastics (not sure the type)

2) What effects of UV-C could I expect to feel on myself? I would only be exposed a few seconds at a time - I imagine that this is much less radiation than I would be exposed while arc welding (used to do that a lot). The bulb I am using is a Ushio G25T8 25 Watt bulb. I can't imagine that this UV source is more dangerous than a 130 ampere arc...

Anyways, I'm working on a biology project to see if I can encourage a culture of bacteria to adapt a resistance to UV-C with the hopes of earning a scholarship or something along those lines. Any help would be great - even if you just point me in the direction of a book!

Thanks.

Your culture will not 'adapt' to the UV light. Rather, there will be a very small sample in the culture that's already resistant to UV. Once your lamp kills off all the non-resistant strains, the resistant strains will flourish (keeping in mind that the mutation responsible for the UV resistance is a hindrance in non-UV environments, which will explain their small numbers in the culture).

Your lamp will give you a deep suntan.
 
I did not mean to imply that I expect bacteria to "adapt" actively in a Lamarckian sense - I meant exactly what you said - I intend to isolate those bacteria which have natural resistance to UV and expand on that culture. If I can determine what mutations render a single cell more resistant to UV, that would be useful information, don't you think? I was inspired to do this experiment by the bacterium D. Radiodurans.
 
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