Timely insights on whole room disinfection.
DisinfectionJune 25, 2021
Can Dry Hydrogen Peroxide Generators Effectively Kill Germs and Viruses?
It’s no secret that effective disinfection has become a hot topic since the COVID-19 outbreak, challenging industries that were often less focused on the spread of illness to improve their cleaning and disinfection standards. As part of this shift, alternate methods of disinfection have entered the spotlight as companies search for the best-fit solution for their needs.
Dry Hydrogen Peroxide (DHP) is one such method that has received increased attention since the pandemic began. DHP systems generate small amounts of hydrogen peroxide through an ionization process of air, which contains moisture/humidity and oxygen. While manufacturers claim the low levels of dry hydrogen peroxide (H2O2) produced is effective at microbial reduction and efficiently fights viruses, bacteria, mold, and odors, there are unanswered questions as to whether this approach works. One thing is for certain, however: DHP systems—as opposed to dry mist or dry fog systems—are not EPA registered.
Has the EPA vetted dry hydrogen peroxide generators?
The EPA is the regulatory body that evaluates disinfectants and sterilants used on environmental surfaces. Any approved solution will receive an EPA registration number that validates its kill claims, uses, dwell or contact time, and more (e.g. EPA Reg. No. 84526-6).
Currently, dry hydrogen peroxide generators are not regulated by the EPA or FDA. While they have an EPA establishment number—which may look similar to an EPA registration number—these numbers are simply used to report production figures to the EPA and there are no requirements to acquire them. Despite this, some DHP companies use the establishment number to mislead customers into believing it is a registration number that confirms the system has been evaluated by the EPA or FDA. It is important to be aware that the technology has not been evaluated or approved by either agency.
Is it considered safe for use around humans?
The premise of DHP is that it is continuously circulated throughout rooms to kill germs. While the H2O2 will come into contact with pathogens in air, people within the rooms are also constantly exposed. Since high levels of H2O2 can be dangerous to humans, OSHA has set a permissible exposure limit (PEL) of 1 part per million (ppm) as an 8-hour Time Weighted Average (TWA) for hydrogen peroxide exposure. Constant monitoring must be done to assess that an area remains within the accepted thresholds for safety. Even if safety thresholds are maintained, this does not consider that, if made aware, many individuals would not want to continuously breathe in H2O2, regardless of approved levels.
Is it practical and works reliably?
Currently, there is limited data published regarding dry hydrogen peroxide, calling into question the very notion that it can work in a real-world environment. Most notably, the premise of these generators is that they maintain a continuous, low level of H2O2, and when this level is maintained, germs are killed. However, the environments that are being treated are being ventilated regularly. For instance, buses and trains open their doors constantly to fresh air, and HVAC systems in buildings exchange air several times each hour indoors. When faced with these real-world scenarios, there is limited data to show that the necessary levels can be maintained. Further, because these devices are not regulated, manufacturers can use general statements to claim efficacy against certain viruses—some of which are easy to deactivate. But higher-level pathogens like spore forming bacteria likely will not be eliminated with these devices.
Is it proven to be effective?
Companies that sell DHP generators say that they produce H2O2 in very low ppb or fractions of ppm. But the problem is that measuring these low amounts is very difficult and nearly impossible for the average user. Rather than being able to test it themselves, or rely on EPA research and clearance, users must believe the manufacturers claims. Data has also suggested that these systems only produce a 1-log reduction. Comparatively, other registered disinfection solutions—like Halosil’s HaloMist™—have up to a 6-log rate kill claim.
So, what’s the answer?
Before investing in a dry hydrogen peroxide generator, it is critical to consider these fundamental concerns. If looking for a hydrogen peroxide-based solution that has been evaluated by the EPA, it is better to consider dry foggers. These systems are used only in unoccupied rooms, and uniformly reach every nook and cranny of an environment with a hydrogen peroxide dry fog. The concentration of hydrogen peroxide is high enough that it is proven to effectively disinfect against germs, and then decomposes into harmless water and oxygen particles before a disinfected room is reoccupied.
Speak to a Halosil specialist today to learn more about the power limitations of dry hydrogen peroxide generators and to discuss alternatives.