Ionisers are tops for scent killing. There's 2 basic kinds, high voltage corona discharge types and ultraviolet (UV).

Corona types are very cheap, very effective scent killers and easily home built. They are nothing more than a stack of diodes and capacitors connected as a string of voltage doublers to AC mains voltage. However, corona types create nitrogen oxides (NOx) which mix with humidity to form nitric acid (HNO3). Grow exhaust air treated with corona ionisers must vent directly to outdoors. If you vent into a building void (attic, crawlspace), the nitric acid could corrode steel structural parts like joist nailer plates. Bad bad bad. Grow op not allowed to hurt house.

UV types are much more expensive, but do not give off NOx and thus don't create HNO3. However, most UV types are single 10-15 watt fluoro tube units and can not treat large volumes of air.

The answer is more UV tubes. Here's a commercially made multi-tube UV ioniser by Big Blue Air:



The 5 tube, 10" version makes 4000mg/hr of ozone, suiting up to 1200CFM of airflow.

Problem is... it's $US600, would cost $150 to deliver from the US and would need a 110v-240V transformer (another $150) just to run on my local AC mains.

I strongly suspect I can replicate this for a lot less than $900 and build it to suit 240V 50Hz. Mounting 5 UV tubes inside a piece of steel duct sounds like quick work.

I've started combing the lighting suppliers for ballasts and tubes. Found some 20W tubes and if the cost is OK, I'll use 5. Should be able to get 5500mg/hr O3 our of 5x 20w tubes. Housed in a length of 10" duct, it should have no trouble treating my exhaust fan's 280litres/sec (600CFM) flow rate.

yee haw, babay... bigger, better, more.

Will post construction notes & pix as I accumulate the parts. Will be an afternoon's assembly project.

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Get a harvest every 2 weeks - A batch of clones in rockwool - Al B. Gone

Curious, aren't those the bulbs used in an aotoclave (sp) used by Doctors and tattoo artists? VV

Dunno VV, I've never torn an autoclave apart. It would make sense as these UV lamps are also germicidal.

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Get a harvest every 2 weeks - A batch of clones in rockwool - Al B. Gone

what is the nanometer reading of those lights you found? i have been looking for some UVB bulbs (280-300nm) but cant really find much more than 6" bulbs use to dry finger nails.

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fdd2blk she said she wanted 12 inches, so i gave her 4 three times.
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Pretty sure they're at 253.7nm. I think that's the frequency of emission for all mercury vapour germicidal lamps. The tubes I've found I believe are UVC.

I have just found a 115 watt single tube as well, but it is in a 4' long conventional fluoro tube, type TUV115VHO-R. One of these 115 watt UV death monsters could theoretically do the job for me. Checking into this a little further.

Thought about this a bit and decided that the scent of ozone itself is a giveaway, so I'm going to continue on the multi-lamp path, with individual, remote power switches for each of the 20W tubes. This way I can dial down the O3 if it is noticeable where it should not be.

Seeing which UV tubes have lighted would be hard in a duct, which is tucked in a difficult to reach place in my op. I could put some photocell operated nightlight circuits in the duct housing the UV tubes, photocells masked so they only see one UV tube at a time, to trigger some indicator lamps (or LEDs) to indicate if any the UV tubes has burned out. Might also be able to simplify this with some optical fibres run to the switchbox. Optical fibres would allow one to see the actual UV tube light.

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Get a harvest every 2 weeks - A batch of clones in rockwool - Al B. Gone

ive been looking for a few UVB bulbs for a while now with no luck. if you come cross any drop me a PM and let me know please. all i can find are the 6" and those would be pointless to try on a large area without haveing 20000 of them. im looking for atleast 2' but 4' would be better

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fdd2blk she said she wanted 12 inches, so i gave her 4 three times.
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Will do.

Lamps On Line seem to have a very wide selection of UV tubes. UK based.

They have some bigmuthahompin' UV tubes. Surely they have something big enough for your application.

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Get a harvest every 2 weeks - A batch of clones in rockwool - Al B. Gone

i took a look at that site and didnt find any UVB lights at all, but i may have over looked them. but thanx for the link ill look at it more when i get the chance

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fdd2blk she said she wanted 12 inches, so i gave her 4 three times.
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damn, sorry about that. If I find anything else, I'll let you know.

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Get a harvest every 2 weeks - A batch of clones in rockwool - Al B. Gone

eBay.co.uk: 240VAC IONIC BALL AIR PURIFIER IONIZER BREEZER W OZONE (item 220113811487 end time 22-May-07 07:00:00 BST)
I got one of these when i started growing.

I think it works along the same lines to what your saying and for its little size it is quite effective in odour control and so far I havent felt compelled to buy anything else, I may well invest in a carbon scrubber aswell once i start flowering all these clones i got growing.