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Doc_T
Random Dude




Registered: 03/06/09
Posts: 42,395
Loc: Colorado
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Re: Perhaps, a legitimate mycology use for UV [Re: andymc]
#14800021 - 07/20/11 08:19 PM (12 years, 6 months ago) |
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Good stuff man! See if you can get pics of the plates at equal intervals, every 8 hours or every 12. That will give you a more even comparison.
-------------------- You make it all possible. Doesn't it feel good?
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CheeseBurgler
Lurker Aficionado



Registered: 03/31/11
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Re: Perhaps, a legitimate mycology use for UV [Re: Doc_T]
#14800485 - 07/20/11 09:46 PM (12 years, 6 months ago) |
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this is my favorite thread, as of recent time.
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sandman420
Saint PP



Registered: 06/17/04
Posts: 5,384
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Re: Perhaps, a legitimate mycology use for UV [Re: CheeseBurgler]
#14802158 - 07/21/11 08:39 AM (12 years, 6 months ago) |
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you should wear welding goggles if you are going to be in the vicinity. There are some good uses for UV light for sure. Sterilizing flowhood work surfaces, foil squares, tools, empty plates that are suspected of having the package breached, even poured plates can be doubly sterilized for shits and gigs.
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Doc_T
Random Dude




Registered: 03/06/09
Posts: 42,395
Loc: Colorado
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Re: Perhaps, a legitimate mycology use for UV [Re: sandman420]
#14804143 - 07/21/11 04:31 PM (12 years, 6 months ago) |
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^^^ bad advice, UV is too dangerous for casual use. Would you sterilize your surfaces with gamma rays? Hard x-rays? UV light is the same stuff, it's high-energy ionizing radiation. Not as bad as that stuff I mentioned, but bad.
Using welding goggles (and gloves!) reduces the risk, but there's still not enough benefit to make it worthwhile.
-------------------- You make it all possible. Doesn't it feel good?
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andymc
cocoa beetles from zanzibar



Registered: 11/25/09
Posts: 2,395
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Re: Perhaps, a legitimate mycology use for UV [Re: Doc_T]
#14804973 - 07/21/11 07:07 PM (12 years, 6 months ago) |
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Here are some photos after 48 hours.
Here we have the untreated plates on the left, and the UV-treated plates on the right (can't see much from these):

The untreated plates are obviously contaminated with bacteria. The whole area where the spore solution dropped is a shiny pool:

But here are the UV-treated ones. At first glance they don't look great either, but you can see little dots of mycelium:
 
If these work out the way my other one did, the treated plates should start to take off and grow out from that initial spot. Unfortunately I think I might have ruined one of these whilst taking photos; I touched the inoculated spot with my zoom lens
-------------------- How I make spore prints Trade List My flow hood If he asks me "Did you have a good time?" I'll say, "Get the lights, Mr. Grim Reaper" -odds
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CheeseBurgler
Lurker Aficionado



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Re: Perhaps, a legitimate mycology use for UV [Re: andymc]
#14805151 - 07/21/11 07:49 PM (12 years, 6 months ago) |
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yeeeeeeaaa pictures!
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andymc
cocoa beetles from zanzibar



Registered: 11/25/09
Posts: 2,395
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Re: Perhaps, a legitimate mycology use for UV [Re: andymc]
#14814943 - 07/23/11 07:31 PM (12 years, 6 months ago) |
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48 more hours. I had a difficult time getting my camera to focus on them tonight, but you can see that the mycelium is spreading out from the dodgy spots:

The one on the right, which I smushed with my camera the other night, seems to be doing surprisingly well. It's got a little spot of something near the edge of the dish, but I'm not too surprised, given that I keep opening them up to take pictures. The experiment seems to be working out, in any case
-------------------- How I make spore prints Trade List My flow hood If he asks me "Did you have a good time?" I'll say, "Get the lights, Mr. Grim Reaper" -odds
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Fungi4TW
Hillbilly



Registered: 06/27/11
Posts: 40
Loc: Northwest Georgia
Last seen: 11 years, 4 months
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Re: Perhaps, a legitimate mycology use for UV [Re: andymc]
#14818953 - 07/24/11 05:51 PM (12 years, 6 months ago) |
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The light from a UV lamp is hardly a danger to anyone. I would (might) wear regular old clear safety glasses. Polycarbonate blocks 99.9% of all UV rays. Wearing a welding hood? Now THAT would be dangerous, as you'd be at a high risk of walking into shit/tripping.
Seriously, that little ass lamp is nothing compared to spending a day in the sun, or your GF going to a tanning bed.
On top of it all, most of the vitamin D in your body came from being exposed to UV rays. During the winter something like 90% of all Americans have a vitamin D deficiency. This is why there is a flu "season", why you are more prone to getting sick in the winter.
-------------------- Yes ma'am, that IS a screwdriver in my pocket!
Edited by Fungi4TW (07/24/11 05:52 PM)
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andymc
cocoa beetles from zanzibar



Registered: 11/25/09
Posts: 2,395
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Re: Perhaps, a legitimate mycology use for UV [Re: Fungi4TW]
#14824373 - 07/25/11 08:01 PM (12 years, 6 months ago) |
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Alright, last one. 48 more hours.
I think it's safe to say these guys are home free

It's not very scientific, but I think I'm satisfied that UV disinfection can salvage a bacteria-infected spore syringe, at least on agar. My experiment ended up 6-for-6 with this syringe: 3 contaminated dishes without UV, and 3 clean dishes with.
-------------------- How I make spore prints Trade List My flow hood If he asks me "Did you have a good time?" I'll say, "Get the lights, Mr. Grim Reaper" -odds
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mushroomfever
Stranger


Registered: 03/24/13
Posts: 23
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Re: Perhaps, a legitimate mycology use for UV [Re: andymc]
#18109367 - 04/14/13 06:05 PM (10 years, 9 months ago) |
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This thread is worth a bump for sure.
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fastfred
Old Hand



Registered: 05/17/04
Posts: 6,899
Loc: Dark side of the moon
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Re: Perhaps, a legitimate mycology use for UV [Re: mushroomfever]
#18110866 - 04/14/13 11:12 PM (10 years, 9 months ago) |
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Funny to see there is still fearmongering going on over UV. It can give you a nasty burn, especially your eyeballs. It's much more of a red painful burn than sunburn, so don't even think about using it to tan. But any plastic lense glasses will protect your eyes, and you can use any normal method to protect your skin. Limit exposure, limit exposed skin, and/or wear sunscreen. If you take even the most basic and simple of precautions you should have no problem. One good burn will teach you the lesson anyways.
Here is my quick guide on getting your UV going...
Google "t8 uv germicidal lamp". Click on shopping, that should give you any number of sites. I suggest the one that is the cheapest source, around $6.88. You want one that is G15T8. This should work in a F15T8 light fixture.
Go to your local MegaMart or hardware store. Buy an 18" fluorescent light fixture for one 15W bulb. Under-Cabinet types will usually have a switch on the cord or fixture and be cheaper. Strip light type will be a little more and probably not have a switch, but they will be metal (withstands/reflects UV better). They are about $8 and $14, respectively. Make sure to take any plastic cover or diffuser off.
Now you've got a 15W, 18" germicidal lamp for just under $15.00!
Remember you're not trying to replace all your good sterile technique, such as swabbing down surfaces with disinfectant. But "LYSOL Professional Brand III Disinfectant" is $9.99 at my local MegaMart, and you can certainly reduce your disinfectant consumption significantly by letting UV do the work.
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Khii Khwaay
black tooth grin

Registered: 04/16/12
Posts: 2,277
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Re: Perhaps, a legitimate mycology use for UV [Re: fastfred]
#18111145 - 04/15/13 12:39 AM (10 years, 9 months ago) |
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Fucking very cool. 5 for you.
Are you the gentleman that wrote my favourite agar recipe?
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jjhitman
The Harley Guy



Registered: 09/27/09
Posts: 286
Last seen: 3 years, 5 months
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Re: Perhaps, a legitimate mycology use for UV [Re: Khii Khwaay]
#18111252 - 04/15/13 01:19 AM (10 years, 9 months ago) |
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-------------------- Put water in a cup, it becomes the cup. Put water in a tea pot, it becomes the tea pot. Water can crash or water can flow. Be water my friend.
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veda_sticks
Cultivator




Registered: 07/29/07
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Loc: UK
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Re: Perhaps, a legitimate mycology use for UV [Re: jjhitman]
#18111468 - 04/15/13 03:42 AM (10 years, 9 months ago) |
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Ive heard of UV-C ligth being used to sterise or at least clean stuff I think water.
But bear in mind that those UV lights dont specifically affect just bacteria or molds or stuff you just want to kill. It affects everything. Mushroom mycelium and spores i guess.
Quote:
Ultraviolet germicidal irradiation (UVGI) is a disinfection method that uses ultraviolet (UV) light at sufficiently short wavelength to kill microorganisms.[1] It is used in a variety of applications, such as food, air and water purification. UVGI utilises short-wavelength ultraviolet radiation (UV-C) that is harmful to microorganisms. It is effective in destroying the nucleic acids in these organisms so that their DNA is disrupted by the UV radiation, leaving them unable to perform vital cellular functions.
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Effectiveness
The effectiveness of germicidal UV in such an environment depends on a number of factors: the length of time a micro-organism is exposed to UV, power fluctuations of the UV source that impact the EM wavelength, the presence of particles that can protect the micro-organisms from UV, and a micro-organism’s ability to withstand UV during its exposure.
In many systems redundancy in exposing micro-organisms to UV is achieved by circulating the air or water repeatedly. This ensures multiple passes so that the UV is effective against the highest number of micro-organisms and will irradiate resistant micro-organisms more than once to break them down.
The effectiveness of this form of sterilization is also dependent on line-of-sight exposure of the micro-organisms to the UV light. Environments where design creates obstacles that block the UV light are not as effective. In such an environment the effectiveness is then reliant on the placement of the UVGI system so that line-of-sight is optimum for sterilization.
Sterilization is often misquoted as being achievable. While it is theoretically possible in a controlled environment, it is very difficult to prove and the term 'disinfection' is used by companies offering this service as to avoid legal reprimand. Specialist companies will often advertise a certain log reduction i.e. 99.9999% effective, instead of sterilization. This takes into consideration a phenomenon known as light and dark repair (photoreactivation and excision (BER) respectively) in which the DNA in the bacterium will fix itself after being damaged by UV light.[5]
A separate problem that will affect UVGI is dust or other film coating the bulb, which can lower UV output. Therefore bulbs require annual replacement and scheduled cleaning to ensure effectiveness. The lifetime of germicidal UV bulbs varies depending on design. Also the material that the bulb is made of can absorb some of the germicidal rays.
Lamp cooling under airflow can also lower UV output, thus care should be taken to shield lamps from direct airflow via parabolic reflector. Or add additional lamps to compensate for the cooling effect.
Increases in effectiveness and UV intensity can be achieved by using reflection. Aluminium has the highest reflectivity rate versus other metals and is recommended when using UV.
Quote:
Inactivation of microorganisms
The degree of inactivation by ultraviolet radiation is directly related to the UV dose applied to the water. The dosage, a product of UV light intensity and exposure time, is usually measured in microjoules per square centimeter, or alternatively as microwatt seconds per square centimeter (µW·s/cm2). Dosages for a 90% kill of most bacteria and virus range from 2,000 to 8,000 µW·s/cm2. Dosage for larger parasites such as Cryptosporidium require a lower dose for inactivation. As a result, the US EPA has accepted UV disinfection as a method for drinking water plants to obtain Cryptosporidium, Giardia or virus inactivation credits. For example, for one-decimal-logarithm reduction of Cryptosporidium, a minimum dose of 2,500 µW·s/cm2 is required based on the US EPA UV Guidance Manual published in 2006.[6]:1-7
Advantages For more details on this topic, see Disinfectant.
UV water treatment devices can be used for well water and surface water disinfection. UV treatment compares favorably with other water disinfection systems in terms of cost, labor and the need for technically trained personnel for operation: deep tube wells fitted with hand pumps, while perhaps the simplest to operate, require expensive drilling rigs, are immobile sources, and often produce hard water that is found distasteful. Chlorine disinfection treats larger organisms and offers residual disinfection, but these systems are expensive because they need a special operator training and a steady supply of a potentially hazardous material. Finally, boiling water over a biomass cook stove is the most reliable treatment method but it demands labor, and imposes a high economic cost. UV treatment is rapid and, in terms of primary energy use, approximately 20,000 times more efficient than boiling.[discuss] Drawbacks
UV disinfection is most effective for treating a high clarity purified reverse osmosis distilled water. Suspended particles are a problem because microorganisms buried within particles are shielded from the UV light and pass through the unit unaffected. However, UV systems can be coupled with a pre-filter to remove those larger organisms that would otherwise pass through the UV system unaffected. The pre-filter also clarifies the water to improve light transmittance and therefore UV dose throughout the entire water column. Another key factor of UV water treatment is the flow rate: if the flow is too high, water will pass through without enough UV exposure. If the flow is too low, heat may build up and damage the UV lamp.[7]
-------------------- PF TEK - writeup by EvilMushroom666 Lets Grow Mushrooms - RogerRabbit & RoadKills website with sample videos plus the full PF TEK video series. Alot of great information - BUY THE DVD Cakes can and will pin! - So you think cakes suck for pins. Your wrong Franks Simple Coir/Verm Tek Franks Proper Pasturisation Tek Franks Spawning To Bulk - Monotub Professor Pinheads RTV Injection Port Tek Foo Mans No Soak WBS Prep Tek
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wildernessjunkie
Reshitivest



Registered: 06/13/10
Posts: 8,118
Loc: HTTP 404 Not Found
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Re: Perhaps, a legitimate mycology use for UV [Re: veda_sticks]
#18111530 - 04/15/13 04:41 AM (10 years, 9 months ago) |
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Using these lights, how much exposure time is required to sterilize? Anyone have an educated guess on the time that would be necessary to sterilize air, surfaces, or exposed agar?
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fastfred
Old Hand



Registered: 05/17/04
Posts: 6,899
Loc: Dark side of the moon
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Quote:
Are you the gentleman that wrote my favourite agar recipe?
Quite possibly, although I can't take credit for much more than a bang up cut-n-paste job.
Quote:
Using these lights, how much exposure time is required to sterilize? Anyone have an educated guess on the time that would be necessary to sterilize air, surfaces, or exposed agar?
That's the tough part. It usually has to be determined experimentally.
There's just too many factors to consider. The power of your light is a big factor, and that can vary by the quality of the ballast and also over the life of the bulb. An 18" 15W bulb will also have a different concentration of UV than an 8" 15W bulb, and so forth.
Distance from the contam and the type of the contam also matters. Most organisms are used to dealing with some amount of UV from the sun. Some are tricky and have pigments or form protective films.
UV works best to sterilize clean surfaces. A surface you wipe down will accumulate a fine layer of contams, and UV can quickly burn these up.
UV won't burn through a bunch of grime and anything shaded from the light will not get sterilized. Generally all plastics and most glass will stop UV rays also.
The best setup is for a sterile room, hood, or transfer station. You simply turn the UV on when you leave and off when you come back. That way you always start with a sterile area and clean air. UV can only really sterilize still air where the contams drift slowly through the UV light and get burned up.
Normally the UV will work in a couple minutes at close range. UV is very effective at what it does, but because of it's limitations you still need to practice good sterile technique. It will give you better results if your technique is weak or you have a high contam load or poor facilities.
Restaurants, hospitals, etc. often use UV to help keep the air clean. They use UV tubes shining against a wall with a shield to protect the room. Normal convection and the heat from the tube(s) will keep air slowly moving up through the UV "kill zone". This is a great way to reduce the contam load in your air.
I'll probably put together a guide at some point, but heed the warnings now! UV will give you a nasty burn, and it will NOT feel like a nice day in the sun, nor will you get a tan from it. Tanning beds use UVA and UVB rays, NOT germicidal UVC! UVC is the "bad" rays that do the most damage to any DNA in their path.
Burning your eyeballs with UVC does NOT feel good! A buddy told me (didn't listen to my adamant warnings) that his eyes felt like sandpaper for almost a week. UV is implicated in cataracts and skin cancer, so use protection!
But, just use common sense and you'll be fine. Never look directly at UV light, and always wear eye protection. Any kind of plastic lense glasses or safety glasses will work just fine for protection. You should never need to have even a moment of bare eye exposed to UV.
Your skin is a lot tougher, but still should be protected. A couple minutes of normal strength UV on your skin per day will cause no effect. However, it is very easy to forget about the UV and end up working for awhile and getting exposed. A half hour can often burn you, and an hour can give you a nasty burn. I've only ever been lightly burned, but it's something I'll not repeat. I thought I was not getting much exposure, but even 15-20 minutes at close range is too much.
So you should never work under UV light. It's too easy to forget and work too long, or underestimate your exposure level. Working under UV is not that useful and isn't using UV in the optimum way. If you do want to use UV while you work, that's fine. Just make sure to wear gloves and a long sleeved lab coat. Make sure to check if any skin is exposed. If it is then cover it up or put on some high SPF sunscreen.
One last note... UV is destructive to just about everything. It will fade paint, crack vinyl, and make plastics brittle over time. Don't be surprised if all your plastic starts to crumble after a few months of leaving the UV on when you're not around. If that's a problem for you then get electrical twist timer so you can kick the UV on for an hour or two before you want to work.
-FF
-------------------- It drinks the alcohol and abstains from the weed or else it gets the hose again. -Chemy The difference between the substances doesn't matter. This is a war on consciousness, on our right to the very essence of what we are. With no control over that, we have no need to speak of freedom or a free society. -fireseed "If we are going to have a war on marijuana, the least we can do is pull the sick and the dying off the battlefield." -Neal Levine (MPP) I find the whole "my drug should be legal but yours should be illegal" mindset disgusting and hypocritical. It's what George Bush and company do when they drink a cocktail and debate the best way to imprison marijuana users. -Diploid
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andymc
cocoa beetles from zanzibar



Registered: 11/25/09
Posts: 2,395
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Re: Perhaps, a legitimate mycology use for UV [Re: mushroomfever]
#18113671 - 04/15/13 03:50 PM (10 years, 9 months ago) |
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Quote:
mushroomfever said: This thread is worth a bump for sure.
Thanks!
Quote:
wildernessjunkie said: Using these lights, how much exposure time is required to sterilize? Anyone have an educated guess on the time that would be necessary to sterilize air, surfaces, or exposed agar?
Just using my little wand, powerered by AAA batteries, 10-15 seconds of UV per spot on the agar seems to do the trick (each spot was 2-3 drops of spore solution).
Thanks also for the additional info fellas.
-------------------- How I make spore prints Trade List My flow hood If he asks me "Did you have a good time?" I'll say, "Get the lights, Mr. Grim Reaper" -odds
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