Guest guest Posted December 12, 2006 Report Share Posted December 12, 2006 Don, If you check with chemical disinfectant product manufacturers, most of them do not have efficacy data for microbial indices involving a biological cleanup in sewage or mold contaminated buildings. In fact, their EPE rating is based on killing a certain amount and type of organisms on a clean surface. In calling a couple of chemical manufacturers several years ago, their product claims are based on cleaning up the contamination first before applying their product. One manufacturer said, their product is for hospital use, where non-porous surfaces are present. They would not support dilution claims for use on porous or soft surfaces. From: iequality [mailto:iequality ] On Behalf Of Schaezler Sent: Monday, December 11, 2006 6:12 PM To: iequality Subject: Re: QPCR : I am talking about disinfecting clean, hard and/or semi-porous surfaces like wood, metal, vinyl, and concrete with diluted bleach. The surfaces should be well-cleaned prior to disinfecting. Obviously porous material like carpet should be discarded. The main point I was trying to make is that the mass of water added is not a problem if the disinfectant is used judiciously. The second point is that diluted bleach works well as a disinfectant. Diluted bleach was specifically recommended by CDC for removing mold and cleaning mold-contaminated hard surfaces following hurricanes. Don Schaezler Moffett wrote: > > Don, > In our own in-house study right after the 1994 water damage standard > came into public domain, we looked at disinfecting carpet back to its > pre-loss condition: When the carpet was sewage saturated, any amount of > disinfectant wouldn't work until the biological load was removed and the > carpet was purged of its effluents. Even then, the carpet samples were not > considered disinfected to a sanitary condition until they were detergent > washed multiple times, where the disinfectant was considered worth trying > under those conditions. > If you have a disinfectant magic bullet or wand that can be waived > over sewage contaminated carpet for example, please let us know. > In 1995, from our studies we determined, if you have 1 gallon (e.g., > 8.5 pounds) of sewage soaked into a carpet and then soak the same carpet > with an equal amount of wide-spectrum disinfectant, the carpet was > found not > to be clean or sanitary after drying. > Moffett > > Re: QPCR > > : > > I think these percentages, out of context, are meaningless. The > questions are: > How many lbs/sf of disinfectant solution will be used? > Will this application effectively disinfect the surfaces treated with > respect to fungal and bacterial contaminants? > Will this application significantly raise the moisture content of the > material treated? > If so, will the dehumidification in place dry the material in a > reasonable time frame? > > For example, assume one gallon of disinfectant solution is used to treat > 100 sf of material (a fairly generous amount, I think), and that the > solution soaks into the material a depth of one inch. I calculate that > we will be adding about 8 pounds of water to 8 cf of material. If the > material is concrete, we will raise the moisture content about 0.7%. If > the material is wood, we will raise it about 2.5%. > > These moisture increases are relatively minor. The remaining question is > will the 0.04 pounds of hypochlorite do the required disinfecting or > will a higher mass and concentration be required? > > On sewage backup/flooding projects, I have had good results with bleach > solutions disinfecting surfaces (i.e., no enteric bacteria remaining), > if a good cleaning job has been done prior to application of the bleach. > > Don Schaezler, Ph.D., P.E., CIH > ETC Information Services, LLC > 19349 Old Wiederstein Road > Cibolo, Texas 78108 > > fax > mobile > donaldschaezler (DOT) net <mailto:donald%40schaezler.net> > > Moffett wrote: > > > > , > > > > On a side note: Your comment about using bleach - I spoke extensively > > with Dr. Chin Yang some years ago and it was his opinion, and I agree, > > that household chlorine bleach is 5.25 active ingredient > > (hypochlorite), and diluting it to a 10% solution results in an active > > ingredient of .5% with the other 99.5% being water. The activity of > > the .5% is overcome in mold remediation by the 99.5% water. Chin and I > > feel scenario outweighs the benefit of using household bleach when it > > is diluted to this degree. > > > > > > > > ---------------------------------------------------------- > > FAIR USE NOTICE: > > This site contains copyrighted material the use of which has not > always been > specifically authorized by the copyright owner. We are making such > material > available in our efforts to advance understanding of environmental, > political, human rights, economic, democracy, scientific, and social > justice > issues, etc. We believe this constitutes a 'fair use' of any such > copyrighted material as provided for in section 107 of the US > Copyright Law. > In accordance with Title 17 U.S.C. Section 107, the material on this > site is > distributed without profit to those who have expressed a prior interest in > receiving the included information for research and educational purposes. > For more information go to: > http://www.law.cornell.edu/uscode/17/107.shtml. > <http://www.law.cornell.edu/uscode/17/107.shtml.> > If you wish to use copyrighted material from this site for purposes of > your > own that go beyond 'fair use', you must obtain permission from the > copyright > owner. > Quote Link to comment Share on other sites More sharing options...
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