Decontamination FAQs

It’s true that ozone can degrade materials such as plastic. However, under normal use the concentration produced by the BIG BLUE and the short contact time is not nearly enough to cause any kind of problems. It takes a tremendous amount of ozone to cause this type of damage, and the contact time would have to be months/years, not hours/days.

Most growers will find the BIG BLUE  works well for two applications: sterilizing your grow space between grows, and as part of a grow room exhaust system for controlling odor. To rid the grow room powdery mold, mildew and insects simply pair your BIG BLUE with an inline fan and timer. A 6in BIG BLUE will clean a 2600 cu ft grow space in under an hour. When using the BIG BLUE as a scrubber you can use a high static pressure, low cfm fan. Ozone works best when it can maintain a high concentration in an enclosed space, so shut off your exhaust and carbon filters. Circulating fans are helpful to leave on, if you have them. Generally we recommend running the BIG BLUE for a couple of extra hours just to make absolutely sure everything is killed. Give yourself enough time for the ozone to react and then decompose before you re-enter your space (an hour or two is usually sufficient). Use the “sniff test”; if you can’t smell the ozone in the air then you can be certain it’s safe to re-enter.

The ozone produced by the BIG BLUE will kill spider mites and most insects. The concentration of ozone you need to achieve in your space is very high. In this case we would recommend sealing the room completely and running the BIG BLUE for a number of days to build up an extremely high level of ozone in the space. The ozone produced by the BIG BLUE will saturate everything inside of the room and get in spaces chemical sprays just won’t – e.g. behind reflective sheeting and in cracks and crevices. We would recommend airing the space out for at least a few hours and not reentering until the smell of ozone is gone.

There are certainly Ozone meters on the market that will give you a readout in parts per million (PPM), but there’s no need to spend money on an ozone detection system. Your nose will tell you when it is safe to enter. Ozone has a very distinct smell; if you’ve ever been caught in a lighting storm you will remember an acrid, caustic smell produced by the lightning – that’s ozone. Ozone can also be smelled on fresh photocopies. Ozone smells like pool chlorine. Some people also describe it as having a metallic smell. If you smell ozone you should wait to re-enter the room. If you have an exhaust fan now would be a good time to turn it on. Once the distinct smell of ozone is gone, it is safe to enter.

Under normal circumstances you should not need a mixing chamber. The BIG BLUE is designed as an air purification chamber. As the odor-bearing air is exhausted from your grow space it is directed through the ducting and into the BIG BLUE. There, the air is exposed to high intensity ultraviolet light that kills viruses, odors and other volatile organic compounds (VOC’s)  on contact. The BIG BLUE’s polished stainless steel surfaces help to increase this intensity so that “baffling systems” and long lengths of ducting are not required. However, if you are using a BIG BLUE to control odor and the fan is perhaps too strong for the model you chose then the contact time may not be long enough. In this case, simply lengthening the duct run should be enough to sufficiently increase the contact time.

Corona Discharge ozonators use an exposed electrical arc to generate ozone. A byproduct of Corona Discharge ozonation is nitric acid. When mixed with moisture from the humidity in the grow space this corrosive “syrup” contaminates the surfaces that produce the ozone. This requires frequent cleaning of the arcing surfaces or the contamination will reduce the ozone output of the generator.

UV lamps use concentrated ultraviolet light waves to produce ozone. These bulbs do not produce harmful residues. Humidity does not affect their function. There is no need to constantly clean the UV lamps during your grow cycle, unlike with Corona Discharge style ozonators.

Some Corona Discharge units can produce more ozone, but not in high humidity environments. You may have experienced static electricity. This usually happens in extremely dry conditions. However, when it’s damp outside, not so much. For grow room applications where humidity is almost always a factor, this gives a huge advantage to the BIG BLUE and its UV lamps.

One other issue with Corona Discharge units is that you need to run them with some type of baffle. The reason is that these units produce ozone in “chunks”; they generate a set amount of ozone and then release it. It is not a continuous process. We frequently hear from customers who complain that they tried a Corona Discharge unit in their exhaust systems and it did not work because they would smell strong ozone coming out of the system and then smell garden odor because the ozone did not have a chance to mix with all the air exiting the room. The worst part of this is that most ozone manufacturers don’t even offer a baffle box for their units!

The four most effective methods of purifying the air we breathe are: ultraviolet light, active oxygen, purifying hydroxyls, and negative ions. Ultraviolet light produces all of these odor fighters. Ionizers, by themselves, create negative ions which attach themselves to solid particles, such as dust, pollen, soot, smoke, etc.. This particulate then drops from suspension to form a harmless dust. Ionizers alone will not eliminate 100% of the odor causing contaminates.

No. But Ionizers are known to create the “black wall” effect. This is a condition where high levels of negative ions, although considered healthy for you, can blacken walls and furnishings by “magnetically” attaching to themselves.

A filter is not required. But we do sometimes suggest a simple filter to extend the life of your fan. Dust, pet hair and other airborne particles mix with the growing humidity and become a wet mess. This mixture can foul fan blades and mechanisms. Using some old panty hose material stretched over the inlet to the exhaust fan and secured with duct tape will help minimize this contamination. This “panty hose” filter is easily replaced when you do your regular garden maintenance

Small or timed ozonators help remove airborne pathogens, bacteria, viruses, molds and mildew. Though ozone only has a half life of about 30 minutes (before it reverts back to oxygen) these ozonators must be on a timed system. When the smell of ozone becomes objectionable or you experience a headache, it is typically at too high a level.

It is possible to use the BIG BLUE in a sealed room. Short bursts of ozone rather than long, continuous ones are superior when incorporated within your garden setting. It is easy to run your BIG BLUE unit on a repeat cycle timer. For low odor levels 1 to 3 minutes on and 10 minutes off will not produce dangerous levels of 0³. As the odor increases, longer on and off times of up to 3 minutes on for every 10 minutes off will clean the air from a 10 x 10 foot room without harming your plants. Less is more when it comes to ozone.

It is always best to err on the side of caution and not expose yourself unnecessarily to high concentrations of ozone. If you follow the BIG BLUE instructions, (though you may find the odor of ozone objectionable) ozone will not be at dangerous levels in the room. We suggest running the BIG BLUE with  the aid of a timer so that you can turn off the ozonator at least 30 minutes before you enter the grow space. We would also suggest trying to get 5 or 6 complete air exchanges in your room to make sure the ozone is fully dissipated. Functionally, ozone only lasts about 60 minutes before it reverts back to oxygen (O2).

Quote from the American National Standards Institute-ANSI Standards for Ozone.

Page 31 Appendix D.

“Although the decomposition (half life) precludes the possibility of large amounts of ozone being present, ozone, like all chemicals capable of oxidation, is a hazardous substance, and ozone-generating equipment can produce dangerous levels of the gas. The United States Occupational Safety and Health Administration (OSHA) has standards for the exposure to ozone. Research indicates that there are no irreversible effects caused by accidental exposure to low non-lethal concentrations of ozone. As a general principle, however, breathing even low levels of ozone should be avoided at all times. Further information can be obtained from OSHA or the International Ozone Association, Pan American Group, 31 Strawberry Hill Avenue, Stamford, CT 06902”.

A small percentage of people can be considered ozone sensitive. These people will find the smell of ozone, at any level, to be too much. The EPA and the FDA have stated that levels below 0.05 ppm are safe for humans. Again, some people will find any level of ozone approaching this level to be overpowering. Fortunately, it takes long term exposure at levels approaching 0.1ppm to cause any harm. We suggest using a timer with the BIG BLUE and then waiting an hour or so before entering your room just to be on the safe side.

Unlike corona discharge systems, it is not necessary to clean the unit every 3 to 4 weeks. However, you may want to wipe the UV bulb and stainless surfaces clean after every grow cycle. This will keep the BIG BLUE functioning at optimal levels. Be especially careful around the tiny starter lamps as these are fragile.

The volume of air (3000 cfm) that you are pushing through 8 inch ducting is not the issue – ozone contact time is (watch this video for more info). On the one hand the faster the air moves the more ozone is created as the smashing of the oxygen molecules (02), in this environment, creates more 03 ozone molecules. But the downside is that the odors exposure time, to the ozone, is diminished. If you have the space, I would recommend using a 12 inch BIG BLUE, this would allow for shorter ducting runs, if needed. Or exhaust into the attic. Using reducers/enlargers to fit it into your 8 inch ducting. Also, you may wish to have a sheet metal shop construct a baffle box/mixing chamber (click here for a video reference) that would be installed on the downwind/pressure side of the ozonator. This would aid in a more thorough mixing of the odor/ozone in the shortest possible distance.

As you know, ozone is the most dangerous component of smog. This ozone is created when the sun reacts with hydrocarbons (the major component of smog) in the atmosphere. Ozone can be very harmful if you are asthmatic or have allergies. You are also probably aware that ozone is extremely unstable. The measurement of ozone in cities is taken out of doors. If the same measurements were taken inside your home (with the HVAC running and the windows open) it would only be 1/10th of the outside measurement. Also many of the machines that we have in our homes (i.e. laser printers or copiers) can produce harmful levels of ozone for some people! If you have these conditions Blue Air Products would never recommend that you use our products while you are in your enclosed hydroponic garden. When you are using the BIG BLUE to sterilize your grow space between harvest and planting, it should be run on a timer or be turned at least 30 minutes before you re-enter the enclosed garden. This time allows the unstable ozone molecules to revert back to harmless oxygen.

The total life of the lamp (depending on the manufacturing quality and all in use conditions being optimal) is about 18 months of continuous use (to know more, click here for the video). Understand that an old Ultra Violet lamp is much like an old MH lamp – the light may be on, but its growing potential has long since perished. From about the 12th month the ozone output begins to decrease until the 18th month and then you probably will smell very little ozone. It is best to err on the side of caution when replacing the bulbs. Therefore our recommendation is usually 14 to 18 months for replacement.

With the 8 inch BIG BLUE you have 3 bulbs. Unless you’ve undersized for the application, it is unlikely you will have all bulbs working all the same time. In other words you may only have one bulb burning for the first quarter of the growth cycle and then add lamps as the growth and odor increase. Therefore, you would not have to replace all the bulbs at the same time. If you are very serious about your garden maintenance you could date the times for each lamp and buy replacements as needed. The replacement cost as of 03/20 is approximately $50 per lamp. As for maintenance at the end of each grow cycle, it might be prudent to clean the inside reflective surfaces of your BIG BLUE. The polished surface almost doubles the effectiveness of the UV lamps. Also wipe down the bulbs as dust, oils, and fingerprints can negatively affect their performance.

Sizing a fan for the BIG BLUE isn’t like sizing for a carbon filter. Fan size and the CFM rating are not the variables you need to account for. Contact time is the important variable. If you have a 5 CFM fan blowing through a BIG BLUE then you’ll have more contact time for the UV light to kill malodors vs having a 500 CFM fan blow through the same unit. This is more related to the number of air exchanges in a given period you desire for proper plant transpiration. It is not a question of what is best for odor elimination. It is best to use the lowest cfm fan available to accomplish this exchange. Watch this video. BIG BLUE ozonators come in varying diameters from 4 to 12 inches. The larger diameters are not only designed to fit your existing ventilation ducting but also ever higher fan volumes. In other words the 12 inch BIG BLUE will handle more cfm than the 4 inch.