Chlorine dioxide (ClO2) off-gassed from an aqueous solution and reacted incrementally with potassium iodide solutions (sinks). After 30 min, 45% of the initial dose was detected as chlorite ion in the sink, whereas 35% of the initial dose was still in the source. "

****!!!! {Medical device sterilisation.} "As a sterilising agent, ethylene oxide’s days are numbered," "Furthering the progression away from EtO, the FDA newly approved a contract sterilisation facility for medical devices utilising CD gas in late 2020.1 This breakthrough advancement was awarded to ClorDiSys Solutions. The company was established in 2001, beginning as an adoption of technology the founders originally created within Johnson and Johnson. There, medical devices such as interocular contact lenses, sutures, artificial hip joints and more were sterilised internally using CD gas. This facility recently processed the first commercially sold medical device sterilised with CD gas that has US approval. *****A draft Reference File for the use of CD gas has been created, which is developed from ISO and AAMI EtO guidelines. This serves to aid in submission packages to both the FDA and EU regulatory agencies. These tools provide a regulatory roadmap for validating the sterilisation process"

****!!!!****!!!!**** Efficacy of chlorine dioxide (CD) gas generated by two distinct generation systems, Sabre (wet system with gas generated in water) and ClorDiSys (dry system with gas generated in air)" "exposure time is more critical than CT as long as the concentration is maintained within a target range. Additionally, in future building cleanup efforts, lower concentrations may be favored in many instances to avoid issues with material or equipment compatibility" "The CD dose required for complete spore kill on biological indicators (typically, 1E6 spores of Bacillus atrophaeus on stainless steel) was significantly less than that required for decontamination of most of the building materials tested." "for all of the other five materials, the time required to achieve successful fumigation was determined to be independent of the fumigant concentrations used"

Fogging Chemical Disinfectant is a highly refined blend of oxychloro species containing purified sodium chlorite. ...

****!!!!****!!!! "Under the tested treatment conditions, the highest population of surviving spores was found on the paper surface and the lowest was found on the plastic surface (p .05). The 5 mg/L ClO2 gas treatment inactivated 2.5, 3.6, 4.0, and 4.9 log spores per surface on paper, wood, epoxy, and plastic surfaces, respectively. A greater than 5-log reduction of spores was achieved on each surface after the 15 mg/L ClO2 gas treatment. The minimum ClO2 gas concentration needed to completely inactivate the inoculated spores was 30 mg/L for paper and wood surfaces, 25 mg/L for epoxy surfaces, and 20 mg/L for plastic surfaces."

****!!!!**** "Collection of a positive sample from a distance more than 2 m away from the nearest patient traffic implies the virus was in an aerosol." "A pilot SARS-CoV-2 air sampling study conducted at a clinic within a university student health care center" "Following detection of SARS-CoV-2 in air by our March 20 air-sampling study, remediation was accomplished by performing a 2-day decontamination process using a stabilized chlorine dioxide solution (VitalOxide™) delivered through a handheld electrostatic mist sprayer"

"determine differences in treatment (dry or liquid reagent; chlorine dioxide concentration; or illuminated or dark fumigation) means for perchlorate and chlorate" "2 h fumigations with 36ClO2. Across trials approximately 12% of the system radioactivity was present on the tomato itself; 2 to 13% was rinsed from the fumigation tank and its associated parts (stir bar, glass pedestal); 15 to 19% was purged from the tank and trapped into sodium thiosulfate; and 44 to 49% was associated with the reaction sachet itself. Total recovery of radioactivity was 80 to 84%"

"[Chlorine dioxide] gas should punch holes in the hard coating around the anthrax spores and destroy its genetic matter," he said. ``It'll take that spore that's now a hard ball and make a whiffle ball out of it,''

Chlorine dioxide could be safely used to fumigate a US Senate office building, says the US Environmental Protection Agency

"Workers in Washington have finished fumigating offices in the Hart Senate Office Building that had been contaminated with anthrax... Officials involved in the decontamination effort at the Hart building say it is unlike any other cleanup they have ever done before." "So we ended up with essentially a short list of technologies that we believed would be effective," he said. "We went through a lot of those and quickly arrived at chlorine dioxide as being the one that had the best chance at being effective."

" A batch treatment of strawberrieswith 4 mg/liter ClO2for 30 min and continuous treatment with 3 mg/liter ClO2for 10 min achieved greater than a 5-logreduction for bothE. coliO157:H7 andL. monocytogenes.After continuous exposure to 3.0 mg/liter ClO2gas for 10 minfollowed by 1 week of storage at 48C, no aerobic microorganisms were detected and the color of the strawberry surface didnot change significantly (P.0.05). Residues of ClO2and chlorite on strawberries after the treatment were 0.1960.33 mgClO2per kg and 1.1762.02 mg Cl2per kg, respectively, whereas after 1 week of storage no ClO2residues were detectedand residual chlorite levels were down to 0.0760.12 mg Cl2per kg. These results suggest that ClO2gas treatment is aneffective decontamination technique for improving the safety of strawberries while extending shelf life"

"Studies have concluded that the usage of high-volume evacuators, fumigation using chlorine dioxide and hydrogen peroxide vapor (HPV) are effective for aerosol reduction in dental operating sites"

"(BS EN 17272:2020: Chemical Disinfectants and Antiseptics – Methods of airborne room disinfection by automated process – Determination of bactericidal, mycobactericidal, sporicidal, fungicidal, yeasticidal, virucidal and phagocidal activities.)" "Prior to October 2020, regulators have required efficacy data produced using the French standard NFT 72-281. However, the new European standard EN 17272 has replaced this" "The BS EN 17272:2020 standard determines the disinfectant activity of processes used in the medical, veterinary, food, industrial, domestic, and institutional areas, using automated processes for distributing chemicals by air diffusion with no operator manually applying the disinfectant. This includes the disinfection of nonporous surfaces but not that of the air."

"The unpopulated operating room after consulting hours can be kept clean by the use of 4 mg/L of ClO2 gas together with the ACP and the HEPA filter."

***!!!!***!!!!*** "virucidal efficacy was tested in three locations of the room after 1 hour and 2 hours of dwell time. The estimated nominal peak concentration was 15 ppmv in the room." "CD was 99.91% effective for eliminating human coronavirus OC43 in both sachet and capsule fumigant form using both ***fast and slow release mechanisms.**** Rapid fumigant application is suitable for contaminated rooms, ambulances, emergency vehicles, and many types of PPE, most particularly porous PPE materials. The gaseous state of CD allows for rapid diffusion and transfer of the virucidal stable free radical to all surfaces of PPE and indoor areas that would favor virus survival. Additionally, this work suggests CD can be effective at levels with significant margins of safety (little to no exposure and rapid degradation of residuals) providing minimal public health risks associated with the use of CD. "

"At a given ClO2 gas concentration, ClO2 residues on tomatoes significantly (P < 0·05) increased with increasing RH, and there were close correlations between log reductions of pathogens and ClO2 residues on tomatoes."

"Pathogen populations reduced more under 90% than under 50 and 70% relative humidity. No significant differences in reduction levels between 50 and 70% relative humidity."

"Bacillus subtilis subsp. niger spore and Staphylococcus albus are typical biological indicators for the inactivation of airborne pathogens." "inactivation tendency and kinetics for ClO2 gas under different RH conditions (30 to 90%)"

The aim of this study was to investigate the lethal effects of simultaneous treatments with gaseous chlorine dioxide (ClO2) and mild wet heat (55 °C at 100% relative humidity [RH]) on Salmonella enterica in chicken feces on the surface of eggshells. Gaseous ClO2 production decr …

"40 ppm ClO2 had no effect on the internal quality of the table eggs, when comparing with the UV treatment method. The hatchability of hatching eggs was not statistical different between formaldehyde fumigation and 80 ppm ClO2 gas treatment, though the value was decreased at high concentration of 160 ppm ClO2 gas.

"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

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.

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