The higher humidity wouldn't create more ozone, the main use of the ozone in the UoC report was generated by the ozone generator. 80% of the ozone created from the light is used in the production of hydroxls and hydrogen peroxide (H2O2) so it is adding those extra oxygen molecules to the H2O already in the air. The Uof C report also said that the ammount of ozone coming from the RCI was so little that it couldn't even inactivate stuff, so the inactivation was noted as from the RCI plasma itself.
At one section they were useing the ozone generator itself...they broke it down to see what does what. That was where the level reading come from.
If you run it on normal and put a meter in front of it you wont pick up anything. in a tube it maintains .01-.02ppb, which is why EQ has a dual RCI based machine without the ozone generator for Canada...since ozone generators are illegal there.
So if ozone is such an issue toyou trial an RCI cell (not a unit- no ozone generator) and throw it in your system for a week and see if you like it...you will smell a difference within hours.
I think a reasonable person reading the Grinshpun, et. al. report would look at the data saying that the ozone in the 10'X11'X8' chamber with the RCI device operating went from 6ppb to 50ppb in 35 minutes and in the smaller chamber to 50ppb in 5 minutes that the ozone was going to be over 50ppb. In fact in a similar experiment in the same size chamber 10'X11'X8' using an ionizer conducted by the National Center for Energy Management and Building Technologies (NCEMBT 061101) it was found that the ozone level went from 0ppb to 50ppb in one hour. But when the device was left on for six hours the ozone level was 175ppb. Given the fact that the RCI device achieved the 50ppb level in 35 minutes who knows what level it would go to if allowed to run for multiple hours.
Ozone levels, when it comes to ozone producing devices, are based on various factors:
1. Production of ozone (and yes, generally, more ozone is produced in higher humidity)
2. Natural ozone decay
3. The size of the room or chamber in which the device is operating
4. The number and types of surfaces in the room or chamber where the ozone can react
5. The type of and the amount of VOC's and other organic matter in the air in the room or chamber
Inside of a building or residence a 6th factor is outdoor to indoor ozone transfer. This usually runs 20% to 70% of outside levels.
To be fair measuring ozone levels in a chamber is somewhat misleading. There are no surfaces to react with and VOC's are introduced in controlled amounts. However, in my experience the levels produced by the RCI device are sufficient to produce relatively high levels of ozone in small, poorly ventilated rooms which is what I say in the article.
Just as importantly the level of ozone produced appears to be enough to activate indoor ozone chemistry. When you understand this you will understand my concerns with any device that generates ozone indoors. You see, the ozone reacts with VOC's to create millions of sub-micron sized particles and other unhealthy byproducts such as formaldehyde, acetaldehyde, ketones, acids and other nasty stuff in various quantities. The biggest culprits in this chemical soup are the ozone reacting with terpenes or basically anything with a scent like cleaners, perfumes, air fresheners, baby wipes, etc.
It looks like we have some people following this thread that like to read so let me give you some good resources to learn about this:
1. Charles Weschler - was the first to find these reactions - do a search on his name and ozone/terpene and you will get tons of good reading material.
2. A simple explanation is in an article by Richard Corsi entitled "Smog and Lemons"
3. One of the best explanations (more detailed) is by William Nazaroff entitled "indoor Air Chemistry: Cleaning Agents, Ozone and Toxic Air Contaminants" which he did for the California Air Resources Board.
To really understand indoor air chemistry one needs to be familiar with these reactions. Although most of the research has been done with ozone, more is being done with other reactive oxygen species (ROS) such as hydroxyl radicals. (see Nazaroff)
Let me give you an example of what can happen. I placed a small bowl of Pine Sol in a 10'X12'X8' room with an ionizer that produced 2.2 milligrams of ozone per hour. This is the same one mentioned in the NCEMBT report above. The ozone in the room was 30ppb. The baseline particle count was 1,250,000 particles over 0.3 microns per cubic foot. After one hour the particle count maxed out the particle counter at over 9,999,999. The ozone level was 20ppb. To put this in some perspective the highest particle count I have ever had outdoors on a red ozone alert day was 6,500,000. And that was 200 feet away from a major superhighway with over 250,000 vehicles per day of traffic. Some "air purifier."
The truth is indoor air chemistry is complex. When you add elements to the mix such as ozone and hydroxyl radicals, you really do not know the outcome. In fact often what you want is not what you get. And what you get can be more unhealthy than what you started with.
I am curious about your product. I have seen pictures of filters eaten by UV light. BE stated that your PCO units use MERV 12 filters. How do you avoid damage to the filters from it being so close. Does the TiO2 surface block exposure on the filter or is it just far enough away?
Breatheasy, I am not disputing that it may go over in the smaller room, as I have stated before it is not meant to be used in an area that small, so you are using it against manufacturer specs if you put it in one. It did say it was fine when run continuously in a room 100m3.
Even if the ozone level was to go up with the higher humidity, so would the hydrogen peroxide levels which would entail stealing that extra O molecule to complete the process, so as ones production rises so does it's level of consumption leaving you with the same end point of barely no ozone in the end. That is why I ststaed that the Ozone levels won't rise. Maybe in the initial process but not what actually makes it's way out of the machine. The purifying plasma will be more concentrated but that is what you want, more concentration means faster nutralization of microbes without higher ozone levels.
The Ozone function is mainly for sanitization purposes on away mode(which would imply you not being present). The RCI cell itself has no ozone function. It will hit .02ppm if you are lucky in a tube.
I would be curious to see what the difference would be had you only used a cap of pinesol in a gallon of water like normal people would use when cleaning with the product. A bowl of it isn't even going to simulate the results of what actual real-life use would, that is just displaying that when in contact with a bowl of concentrated pine-sol it does create issues. I would want to see it done with a DuctwoRx specifically with no ozone function and see if the hydroxls, hydroxl radicals, Super oxides, peroxides, and hydrogen peroxides didn't take care of the majority of it. That shows what can happen with ozone alone. Ozone is only a very small part of RCI, it is just basically what is left at the end of the process .01-.02ppm.
Since you have test facilities why don't you try one and do the testing yourself and see what the result? As genesis stated UVx Photo Plasma is a very new concept and hasn't been tested as much as PCO... though a lot of the reactions are the same. It is basically PCO on steriods. RGF did a lot of testing with the weaker PHI cell though the plasma is the same...just a weaker version of it. I don't have one right now but I would be willing to lend you one when I get some more if you were willing to test it.
The limitations on running the devices in small, poorly ventilated areas creates a problem with all of the other findings in the U of C study. The data on particle removal was derived from using the device in the 10X11X8 chamber. With no air exchanges and a relatively small space you are maximizing the air cleaning of the ionization. That creates even more concern with the less than 25 cfm Clean Air Delivery Rate on 2 micron size particles found in the study.
Secondly, the findings on the bacteria and viruses were derived in a 3X4X8 foot chamber. Clearly the device would not be advised in such a space. And to claim any effectiveness on surfaces in a room, house or other building would not be warranted based on these tests.
The reactions would be the same with the ozone and Pine Sol (terpenes)whether it was in a small bowl (100 ml) or used in cleaning solutions with water. The difference would be that the ozone/terpene reaction would be quenched quicker. You would probably achieve the same high levels of particles but for a shorter period of time. You might look at the University of Texas study done using a Living Air and various terpenes. (Search for Sarwar, et. al. ozone/terpene reactions) One interesting thing about this study is that they measured particles in the 0.1 and 0.2 micron size ranges. Their results are several orders of magnitude higher than mine.
Also the University of California Irvine is doing some work in this area. I believe they sprayed the terpenes into the chamber.
I have been busy testing other products and have a business to run. However, I have made arrangements to obtain a Fresh Air for testing. Hopefully I will have some results this week.
Just checking my references and I found a great review of the ozone/health impact issue written by Charles Weschler at http://www.ehponline.org/members/2006/9256/9256.pdf
Definitely worth reading to understand the issues. Notice the number of times that nasty formaldehyde comes up in these reactions.
Cool, you should test a Ductworx too, but in a standard system like what you deal with in houses too to see the difference because The cell itself gets you away from the ozone and ionization. The RF ionizer is supposed to go 60ft in all directions so I would be interested in the particle count a day or two later after the air is saturated with ions.
Anyway I will check out those references and add them to my library of stuff I can't seem to organize. Have a great day.
I've been thinking about getting one of these myself. I've seen the references to NASA and found out that NASA actually used a similar product called Airocide. Airocide makes wall mounted systems. They use Titanium as their catalyst and they don't mention any hydro peroxides as one of their scrubbers. How safe are peroxides? I read something about how peroxides could become explosive when combined with other compounds. What kind of metals does DUCTWORX use as a catalyst? If I installed DUCTWORX, is it true that I would have to keep my blower running constantly to avoid a build up of gases? What is the drawback of allowing a buildup of gases? Is there a particular odor associated with DUCTWORX? I don't run the blower constantly. I can program my thermostat to run the blower for ten minutes, every thirty minutes. I do this in the non-ac months and it does get rid of stagnant air. Would wiring DUCTWORX to operate only when the blower does a good idea?
Originally Posted by NHMoldInspector
The TiO2 with UVX creates mostly hydrogen peroxide which is safe. It does also produce hydroxls, hydroxy radicals, peroxides and friendly oxidisers. The Clinical Guide to Pharmacology says that H2O2 is harmless.
Originally Posted by NEWAC
The Ductworx uses TiO2 (Titainium) copper, silver and rhodium. They speed up the process with the titainium and one does something to nitrogen oxide that is good...I would have to look it up. The odor kinda smells a little like ozone at first but after it is in a few days you will only notice it when you first walk in but it will fade withing seconds. It just smells clean.
As for the fan you could use it in bursts or you could put a variflow fan in...just basically a lil fan that is on all the time. You can wire the cell into the blower too if you wanted and that will work fine, I just would prefer to have it running all the time so the veriflow would be better but if you are doing it in cycles it would be fine, it just may take a little longer to do its thing.
-Leaving it on without the fan...The only drawback to a build up of gases is it will smell strong when you first turn the fan on on...with the other two options this would probably be at the bottom of the list of how I would do it though.
NASA's page makes the same claim about RCI. I think they are just talking that type of technology was developed on the international space station, anyway the airocide is the same technology but for a lot larger areas. They have a lot of testing done too. EQ doesn't want to have RCI to be listed as a medical device because there are more restrictions to marketing that type of product but it is cool to see people acknowledge the technology of being worthy of an operating room. We are in a lot of hospitals though...
Their catalyst bed is weird though and it has 6 uv bulbs but the exposure surface in the bed are just strips so I would be willing to bet you get the same ammount of exposure from a 14" Dual core as theirsmaller unit...
Thanks a lot. I think I'm going for it. I'm pretty handy around the house and am planning to install it myself. However, I wouldn't know how to wire it to the air handler. Do you know of a website that explains how to?
Originally Posted by NHMoldInspector
It should have the instructions with it. I got one a month ago and flipped through the book real quick. It comes with a plug on the end so it is more than likely just the same as splicing anything together, maybe if you just look an the air handler specs it will tell you what is what and it should be relatively easy to install. You could always just plug it in to begin with until you find the info. I will ask around. Most of us just hire people to install them. As I understand it, wherever the fan connects is where you wire it to. It might be easier to cut the hole in the supply plenum yourself and have a licenced electrician or HVAC pro wire it. I wouldn't do it myself. (other than mounting it).
The Dual commercial pro comes without a plug specifically for that purpose. Do me a favor and email me after you have had it for a week or so and tell me what you think. NHMoldInspector@ecoquestintl.com or firstname.lastname@example.org.
Have a great week!
I have read almost all the links that have lead to this one. I am confused as to how all these products fit into the HVAC system. I have just completed 3 years of HVAC training at Tidewater Community College " I know Community College" ,but none the less this RCI was never discussed or referred to as a worthwhile product. Filteration was discussed in some detail along with humidity control. With proper filteration and humidity control your IAQ "as taught" should be great. Mine is.:)