By ECRI
The spaces through which we move … sometimes they are barely noticed. But these days, the microscopic details about those spaces are front of mind. With the threat of COVID-19 ever present, technologies that can be used to disinfect the spaces through which we move are garnering significant interest.
To help organizations assess the options, ECRI has produced a series of Technology Briefings on large- and small-area disinfection technologies, including those outlined below. ECRI’s Briefings explore in more detail how a given technology is used, which applications it is best suited to, and the strength of the evidence to support its use.
Chemical Fog Room Disinfection Devices
Chemical fog room disinfection systems disperse a controlled amount of chemical fog to provide supplemental disinfection after manual cleaning and disinfection of nonporous surfaces within an enclosed, unoccupied space. They can be used to disinfect the surfaces of some medical equipment, but are not intended for disinfecting porous surfaces. These systems can be mobile or installed in a permanent location (e.g., OR wall). When used according to the instructions for use (IFU), chemical fog room disinfection systems can help reduce the bioburden on clean and dry solid surfaces in a variety of settings, including for health care applications (e.g., ambulances), in industrial settings (e.g., manufacturing clean rooms), and in commercial environments (e.g., offices).
A few cautions, though: Facilities must verify that the equipment in the room can tolerate both the chemical disinfectant and the fogging application of the disinfectant. In addition, trained staff must temporarily seal HVAC vents, smoke detectors, and outer doors in an enclosed, unoccupied space to prevent the escape of fog during disinfection.
Electrostatically Augmented Disinfectant Spray Devices
Electrostatically augmented disinfectant spray devices, also known as ionic spray devices, apply a layer of disinfectant to a surface after manual cleaning. The electrostatic charge applied by the device improves the dispersion of the spray compared with standard spray bottles. This can reduce the application time and amount of disinfectant needed to provide surface coverage.
These systems provide low-level disinfection of pre-cleaned surfaces. Low-level disinfection is appropriate for noncritical medical devices – devices that may come into contact with skin but not mucous membranes – provided that devices can tolerate both the chemical disinfectant and the spray application of the disinfectant.
The systems are intended for use only in environments that have periods of vacancy and where the occupancy can be controlled. Examples include unoccupied patient rooms, open public spaces, enclosed public spaces that can be closed for several minutes, classrooms, conference rooms and auditoriums.
Far-UVC Disinfection Devices
Far-UVC disinfection devices emit light in the far-ultraviolet C (UVC) range to disinfect air and nonporous surfaces within unoccupied spaces in a variety of settings (health care, industrial and commercial). These devices are permanently installed and may be continuously active or have motion sensors or switches for activation when a room is unoccupied.
Although far-UVC light has been used in some applications for several years, these devices have not been commonly installed in health care facilities. During the COVID-19 pandemic, far-UVC devices have been garnering interest due to claims that the light is safe for human exposure. Research into this question is preliminary, however, and compelling evidence of safety for human exposure is lacking. Thus, ECRI and many other experts currently recommend against using these devices when a room is occupied.
Hydrogen Peroxide Vapor Room Decontamination Devices
Hydrogen peroxide vapor (HPV) room decontamination systems disperse a controlled amount of hydrogen peroxide gas to decontaminate manually cleaned and disinfected surfaces within an enclosed, unoccupied space. The systems can be used to disinfect porous surfaces, such as fabrics, as well as nonporous surfaces, such as compatible medical equipment. (Some equipment may be damaged by HPV decontamination.)
HPV room decontamination systems can be mobile or installed in a permanent location. When used according to the IFU, these systems can decontaminate pre-cleaned, pre-disinfected, dry environmental surfaces in health care, industrial and commercial settings. To prevent the escape of hydrogen peroxide gas during decontamination, trained staff must temporarily seal HVAC vents, smoke detectors and outer doors in an enclosed, unoccupied space.
Upper-Air UV Disinfection Devices
Upper-air UV disinfection systems are installed above the occupied space in a room to disinfect the air. They emit germicidal UV light in a directional manner, with the intention that the UV light stays in the upper portion of the room, away from the occupants. As the air circulates, either actively or passively, it enters the disinfection zone and then returns to the occupied space.
Importantly, upper-air UV disinfection systems do not disinfect surfaces; they are intended only for disinfection of air within a room or other enclosed space. The systems require little effort to use and are well suited for continuous air disinfection in many public and private areas, including patient rooms, public waiting rooms and meeting rooms. Systems with active air circulation may not be suitable for use in ORs with laminar flow systems.
UV Room Disinfection Devices
UV room disinfection devices most commonly take the form of portable towers that emit ultraviolet light to disinfect surfaces and reduce healthcare-associated infections (HAIs). These devices are intended for use on nonporous surfaces within a room or other enclosed space. They supplement manual cleaning and disinfection procedures.
UV room disinfection devices can be used to treat patient rooms, ORs, procedure rooms and other moderate-size, enclosed spaces. Some devices may be used in multiples to facilitate treatment of larger, enclosed spaces, like a physical therapy room.
UV Shoe Sole Disinfection Devices
UV shoe sole disinfection devices emit UVC light to disinfect the bottom of users’ shoes. Some products generate ozone gas in addition to UVC light as part of the disinfection process. When used according to the IFU, these devices can disinfect pre-cleaned shoe soles in health care settings, such as in OR anterooms, as well as in industrial and commercial settings.
ECRI recommends caution when considering this technology. Peer-reviewed evidence showing the effect of UV shoe sole disinfection devices on infection rates is lacking. In addition, the potential exposure to UVC light and ozone gas is a safety issue. Facilities should require manufacturers to verify that UV light is contained within the region of a user’s footprint; UV leakage outside of the footprint could expose users to unsafe levels of UV light. Similarly, manufacturers of devices that produce ozone gas should state the ozone concentration generated during a disinfection cycle. ECRI recommends against purchasing or using devices that expose users and nearby people to levels of ozone gas that exceed the permissible exposure limit set by the U.S. Occupational Safety and Health Administration (OSHA). Moreover, before these devices are used, users should be alerted to wear closed-toe shoes and to cover skin that could be exposed to UVC light.
This article is adapted from ECRI’s series of Technology Briefings on large- and small-area disinfection technologies. Each article features detailed technology overviews and ECRI’s recommendations for selecting systems for specific applications. To learn more about ECRI membership, visit www.ecri.org/solutions/device-evaluations, or contact ECRI by telephone at (610) 825-6000, ext. 5891, or by e-mail at clientservices@ecri.org.