Airborne application methods for chlorine dioxide provide immensely powerful tools, and can be further refined for more widespread use in safe and effective ways.
Studies strongly suggest that SARS-CoV-2 coronaviruses can be transmitted between people not only through large droplets in the air, but also smaller aerosols that travel farther and stay in the air much longer. These aerosols can also settle on surfaces and spread contagion there, or be blown back into air again for further distribution.
For many years, airborne disinfection using chlorine dioxide has been applied by machines in unoccupied areas, or by workers wearing protective equipment. These methods allow rapid disinfection of large spaces, and are now being used extensively to fight the COVID-19 pandemic.
Some uses of chlorine dioxide can require advanced knowledge, handling and equipment to avoid serious risks. Most commercial airborne use has customarily required professional evaluations of room space and air flow, and complex equipment. Chlorine dioxide applications have been used extensively by hospitals, airlines, schools, agriculture, businesses, and governments. However, in more recent years many Chlorine Dioxide disinfectants have been developed, both for businesses and individuals, that are simpler and safer to use. Several of these are on the EPA's List N of disinfectants to use against the coronavirus.
Additional exploration of ideas, and testing can also develop even more new capabilities and products, particularly specialized for use in combating this pandemic emergency. Need for airborne application of a safe disinfectant in areas occupied by people has not previously been as urgent of a need, and Chlorine Dioxide products in the US need registration approval by the EPA before they can be applied in airborne uses in areas where people are present. Useful parallels would be creating interactive website tools to provide customized suggestions for optimal airborne applications based on size and use of rooms in buildings.
Chlorine dioxide at low concentrations in the air has been the subject of many studies. Applied as a gas or in airborne mist, even at very low concentrations it makes strong reductions in pathogens in air and on surfaces. Several studies with people present have been conducted in medical centers, schools and other facilities, with notable success. If application conditions are managed appropriately, chlorine dioxide can be used in ongoing, pulsed, or periodic air distribution to provide consistent, convenient, in-depth disinfection for many occupied areas during this pandemic, including schools, hospitals, businesses, public areas, and homes.
Chlorine dioxide liquid solutions can be dispersed through simple methods at low levels through equipment such as an ultrasonic humidifier or an HVAC system. They can also be sprayed in more concentrated solutions in specific areas via a very fine mist spray bottle, or a hand-held fogger.
When applied through airborne means, chlorine dioxide attacks pathogens not only in the air but also on surfaces where it lands in sufficient amounts. Chlorine dioxide distributes in the air more evenly than many other disinfectant mists, resulting in more comprehensive coverage of surfaces. Because of its small molecule size, it also permeates porous surfaces exceptionally well, and it does not cause bleaching or corrosion concerns in low-level concentrations.
In addition to viruses, chlorine dioxide destroys bacteria, fungus and mold. For people already sick with coronavirus, reducing the quantity of coronaviruses plus a broad spectrum of other pathogens in the environment can give people’s bodies a better chance to fight off sickness. Chlorine dioxide can help clean the air for people who have allergies, who are more vulnerable to coronaviruses. However, it might be best for people who have breathing troubles to not be present in a room when Chlorine Dioxide is sprayed, and to return after letting it dissipate. Chlorine dioxide is already used in some countries in airborne applications to help control spread of flu viruses.
Slow-release products are available that gradually release low levels of chlorine dioxide gas from gels or powders, and are sometimes packaged as deodorizers. Be sure that you only place this kind of product where there is sufficient space and air flow to prevent build-up of high concentrations in air.
Be aware that some products may not have the effectiveness levels claimed, particularly if they are not registered through a regulating agency. For instance, some brands of wearable Chlorine Dioxide lanyard badges have shown little to no effectiveness when tested.
Guidelines for effectiveness and safety should be followed. Concentrated fumes are temporarily released when liquid mixes of Chlorine Dioxide are first being "activated," and should not be inhaled. If making a large quantities, mixing should be done in an area with good ventilation, and a mask may be appropriate. However, the amount is small when mixing a consumer product, and is soon diluted into water.
Important: The fogging/spraying methods and concentrations commonly done by professionals for commercial disinfection are NOT safe for occupied areas. Those methods require people to evacuate an area first, except those who are applying the disinfectant (who need to wear PPE).
Specific ways airborne applications can help with the COVID-19 pandemic
Through using airborne application methods of chlorine dioxide, individuals can be greatly helped to be able to better quarantine and isolate in their homes when they or sick (or know they have been exposed to risk). This will reduce crowding at hospitals.
Also, many people are not careful about possible sickness in their home before someone shows symptoms, though contagion starts well before then. Ongoing airborne disinfection would offer an easy way for people to have general disinfection going on in homes before they even realize a resident is sick.
Disinfection also extends to surfaces on which the chlorine dioxide lands, providing more comprehensive disinfection of areas than just hand-wiping a few spots.
Low-level airborne disinfection can also reduce contagion in other occupied places such as medical, business and public locations. This can help businesses to more safely stay open for employees and customers.
Airborne disinfection by adequate but safe levels of chlorine dioxide through effective diffusion methods can not only reduce coronavirus in air, but also reduce bacteria, mold, and fungus, which helps reduce other infections as well as asthma-related problems. This can help people in homes and hospitals.
Tools for airborne application
Various types of equipment and methods exist that are either designed for airborne applications or have correlated airborne impacts.
Some products we are aware of include spray bottles of liquid, small "shocker" gas-release containers for whole room or auto treatment, high-power sprayers, HVAC systems, slow-air-release encapsulated chlorine dioxide packages, bottles of slow-release gel, packets and sheets with embedded chlorine dioxide that are boxed with fresh produce, evaporation from liquid in containers or on surfaces, small slow-release cannisters for odor and mold control, commercial foggers, and sprayer and fogging vehicles driven on streets.
Related products include chlorine dioxide gas level test strips and detectors, UV-blocking spray bottles and other containers, aquarium-type aerators to speed up liquid evaporation, and various types of humidifiers, including ones specifically designed for diffusion of chlorine dioxide.