Air CD Disinf--High Concentration

"The operational aspects of [Chlorine Dioxide gas] treatments are very similar to traditional fumigations with the exception of a humidity requirement of about 60% RH. Spaces can be sealed or materials tarped with common sealing or tarping materials. Gas is introduced and monitored to reach a CT of 760 ppm-hours for efficacy. Bioassay methods are available to check treatment quality as well.. Low concentration safety monitors are used for leak detection or aeration. Aeration is to the atmosphere. Food processing facilities have been treated from small rooms and spiral freezers, to nearly a million cubic feet... The intention is surface decontamination with the capability to penetrate scratches and equipment assemblies that can harbor pathogens, but not penetrate quite like a traditional insecticidal fumigant. "

****!!!!***** (2020) {This study was done via computer modeling that predicted some significantly different results than real-world. Example: Degradation of ClO2 throughout room was based on rate 1 m from fluorescent lamp. In actuality, little UV reaches beyond a couple meters, so rest of gas in room is unaffected other than gas blown into close proximity.} {Negative byproducts from chlorine dioxide gas fumigation} "previously unconsidered potential consequence of such cleaning technologies: the photochemical formation of high concentrations of hydroxyl radicals (OH), hydroperoxy radicals (HO2), organic peroxy radicals (RO2), and chlorine radicals (Cl) which can form harmful reaction products when exposed to chemicals commonly found in indoor air." "Steady-state Cl concentrations are elevated at all OClO concentrations under bare fluorescent and attenuated outdoor lighting, with little dependence on OClO concentration... because species involved in the reactions that lead to Cl formation, as well as Cl itself, can undergo competing reactions" " Sunlight is attenuated as it passes through windows, such that 3 and 10%, respectively, of UV and visible light ingresses" "We assume a ward volume of 35 m3 with an area to volume ratio of 1 m2/m" " temperature was assumed to be 293 K and 50% relative humidity" "The emissions were set to provide the approximate concentrations reported in the literature for NTD use... 3000 and 350 ppm for OClO (to reflect two commonly used concentrations). This required emission rates of... 0.8 and 0.1 ppm/s to deliver 3000 and 350 ppm of OClO " "The emissions were assumed to last for one hour and then stop. After another hour (at noon), ventilation was resumed at 2 per h. There is very little information in the literature on how long the gases will be emitted during cleaning" "Maximum... concentrations occurred [of] RO2 and Cl with OClO [chlorine dioxide] photolysis. Elevated concentrations may persist for hours... Products from reactions involving radicals could significantly decrease air quality when disinfectants are used, leading to adverse health effects for occupants" "OClO photolysis under attenuated sunlight is ~20 times faster than under bare fluorescent lighting," "O3 levels generated from OClO photolysis are much higher than those commonly attained using O3 as the primary fumigant""Photon fluxes will vary greatly throughout a room" "we suggest that the efficacy of NTDs on reducing loadings of several strains of bacteria should be further studied in the dark and under illumination from different indoor lighting. It is possible that efficacy will be greatly enhanced under common lighting sources such as fluorescent lights due to the production of radicals that may inactivate bacteria more effectively than the disinfection agents." "[This info needs verification:] There is no ClOO absorbance at wavelengths longer than 280 nm"

"Adults of phosphine-susceptible and -resistant strains of [insects] exposed for 2–12 h to a chlorine dioxide gas concentration of 1.40 g/m3 (520 ppm) in an outdoor trailer during July and October of 2015. The mean ± SE temperatures in July and October were 32.8 ± 0.5°C and 24.8 ± 0.6°C, respectively. In July, complete mortality after 5 d was achieved"

2016

{Treatment of stored wheat grain} {PureLine chlorine dioxide used} "Mode of Action of chlorine dioxide against insect pests •Oxidative stress--ClO2 enhances the production of reactive oxygen species (ROS) inside larvae of Tribolium castaneumand Plodiainterpunctella. It also causes more antioxidant enzymes (superoxide dismutase and thioredoxin-peroxidase) being synthesized by gene up-regulation. However excess ROS eventually accumulates and imposes oxidative stress to cells, which leads to the lethal effect."

{ClorDiSys Minidox equipment} {Some ppm concentrations may need revision}

Gas treatment: "Place one gallon of water in a pail, hang the battery-powered aerator on the edge and extend the hose with an air stone to the bottom. Place the pail in the center of the truck on the floor, turn on the aerator and place a 100 gram ClO2 tablet into the pail and exit the truck cab, closing vents, doors and windows for five hours or until vapors cease and water is clear. Leaving overnight is ideal. When the ClO2 solution has turned clear, it can be disposed of." Spray/fog treatment: "Between 250 ppm and 500 ppm, and fill a wet fogger or sprayer with the ClO2 solution. Wet fog or lightly spray all surfaces, ceiling to floor, allowing five minutes of wet contact time... Chlorine dioxide can be used in vapor- or a liquid-form, but as a liquid it is more fragile and its effectiveness is vulnerable to sunlight. Once diluted from tablet- to liquid-form, it has a shelf life of up to six months if stored correctly in an air-tight opaque container out of direct sunlight."

Articles about on using chlorine dioxide gas for decontamination by fumigation, including data about effectiveness against pathogens in different environments.

"Our cost for a full interior disinfecting service is 2 ½ cents a square foot. Same as it has been for the last 17 years. It is a $100 minimum for a service call. This includes all buildings 4000 square feet or less."

Doses for using Clidox-S chlorine dioxide in aerosol foggers in animal facilities ~Univ of S Florida

{Helpful basic info on chlorine dioxide} Fast disinfection of spaces (including inside equipment) using chlorine dioxide gas

**Difficult to use. Learn how to use PureLine's PureVista chlorine dioxide gas to deodorize any odor in cars, trucks, animal transport vans, RV's, boats, campers and more. PureV...

Coronavirus Aircraft Disinfectant spray - the Callington Haven Coronavirus aviation disinfectant sprays have been tested against existing viruses and have been proven to be effective at destroying these germs.

Stratus disinfecting services include commercial deep clean, disinfection services and sanitizing services for your business, office, medical facility or other commercial location. Stratus uses

For

Area Calculator for Gas/Vapor Treatments and Liquid Solutions for mold, smoke or deodorization. Liquid Solution calculator for Water Tank & Line disinfection. Globally, all in-place made chlorine dioxide is sold in grams of ClO₂ produced and in 100 ppm & 500 ppm generation levels.

{Disinfecting from anthrax} "Twenty-seven pilot-scale tests were conducted overall. Test surfaces, or coupons, were typical indoor and outdoor building materials and included carpet, ceiling tile, concrete, glass, laminate, painted wallboard (PWB) paper, galvanized metal, and wood. Known amounts of B. atrophaeus spores were inoculated onto the material coupons, and then the coupons were placed in three locations in a mock office: under a desk, on top of a desk, and above the ceiling tiles (one ceiling tile was removed to allow for fog distribution). The chlorine-based decontamination solutions investigated were pH-adjusted bleach (pAB), diluted bleach (1 in 4 dilution), sodium dichloro-s-triazinetrione (dichlor), and aqueous chlorine dioxide (ClO2)."

2014. {Sabre was the company that did government anthrax fumigation} ***Detailed instructions on fumigation procedures. "C1O2 solution at a concentration level of approximately 1,000-4,000 ppm percent" "minimum temperature of 70° Fahrenheit (F) for at least one hour at all temperaturemonitoring points before introducing C1O2 gas" " three C1O2 precursor chemicals and neutralization chemicals (e.g., 25% sodium hydroxide, 36% sodium bisulfite, 50% hydrogen peroxide, or Erythorbic acid--Note: type and quantity dependent on active scrubbing solution media chosen)" "Dehumidify the building promptly after completion of C1O2 gas removal" "Minimum temperature of 70° F, minimum RH of 70%, and either (a) a minimum C1O2 concentration of 500 ppmv or (b) a minimum C1O2 concentration of 3,000 ppmv at all monitoring locations to start the concentration by time (CT) building exposureclock. Conduct fumigation with a minimum duration of either (a) 12 hours or (b) 3 hours that achieves a minimum CT Clock value of at least 9,000 ppmv-hours at all monitoring locations"

****!!!!****!!!!**** "In comparison, chlorine dioxide required an exposure period of 60 min to reduce both B. atrophaeus and G. stearothermophilus by 5 logs." "For chlorine dioxide treatment, increased the relative humidity within the chamber to 65%." "ClO2 tests at 25°C due to problems with condensation at 35°C on the Minodox/ ClorDiSys/ PrimaTec) photometer lens in the ClO2 generator (external to the chamber and therefore at a lower temperature) causing the decontamination cycle to continually abort." "Recommended (by ClorDiSys) biological indicator to validate processes for ClO2: B. atrophaeus." ***** "The increase in the humidity above that normally found in the chamber may allow the water vapor to microcondense onto surfaces and penetrate into a dried population of microorganisms. Chlorine dioxide readily dissolves in water; if this water has condensed onto the surfaces and surrounds the spores, then there will be greater penetration into the coupons and a quicker kill... Initial slow reduction in survival fraction may be a lack of penetration of water vapor during the preconditioning and conditioning phases, followed by absorption of the ClO2 into the dried spore population on the coupons." [???]

2016

"Comparison of liquid vs. gas showed a 3.7 log reduction with liquid CD and a 7.4 log reduction with gaseous CD with equal concentrations and exposure times" "The (ClorDiSys) Chlorine Dioxide Decontamination Proces"