EXP Casino + Resort White Paper

RISK REDUCTION | 27

Our gaming experts advise for heat pipe, pump around an air-to-air heat exchangers to be considered.

ULTRAVIOLET LIGHT Conventional germicidal Ultraviolet Light (UVC) has been proven effective in inactivating viruses. As noted earlier, the issue with this type of light is that it is a safety hazard for humans if installed in occupied spaces. This light has a wavelength of approximately 240- 300 nanometers. UV light in this wavelength penetrates the outer layer of the skin and eyes and does damage which may lead to cancer or other health issues. (27)

downstream in the fresh air path will eliminate the potential source pathogen source. UPPER AIR UVC Various upper-air UVC devices are designed to generate a controlled UVC field above the heads of occupants and to minimize UVC in the lower, occupied area of the room. The primary objective of upper-air UVC is to interrupt the transmission of airborne infectious pathogens with the indoor environment. For occupied spaces with lower ceilings, various louvered upper-air UVC devices (wall- mount, pendant, and corner-mount) are available for use in combinations and are mounted with at least 2.1 m from the floor to the bottom of the fixture. The fixture should be mounted so that its UV energy is distributed parallel to the plane of the ceiling. Device construction and placement prevent excessive ultraviolet energy from striking occupants below. In areas where there is not a viable

Figure 29. UVC Air Handling Unit and Ductwork Application (29)

When installed inside air handling systems, humans are protected from the light while the viruses in the airstream are effectively irradiated. These conventional germicidal UVC lights have been utilized in air handling systems for a long time and can easily be implemented as a protection device against viruses if the UV energy is distributed uniformly at the appropriate UV dose. There is still a potential safety aspect to using these lamps if access doors to the equipment are not interlocked with the UV light operation, however manufacturers of listed systems have the required safeties built into their equipment. ENERGY RECOVERY Many dedicated outside air system (DOAS) units and fresh air casino air handling units have energy recovery incorporated into their systems to recover energy from the return air, as it is exhausted to the outdoors. Units shall be designed to incorporate energy recovery approaches that do not have the potential to leak back to the fresh air stream being supplied to the space. Our gaming experts advise that heat pipe, pump around and air-to-air heat exchangers be considered. Existing air handling systems with energy recovery should be reviewed by a qualified engineer to confirm if modifications should be made. If systems do have the potential to leak potential virus and/or containments from the exhaust air stream to the fresh air stream, existing UVC installed

opportunity for duct mounted UVC (i.e. spaces with minimal or no ventilation), upper-air UVC is a very promising approach.

Figure 30. Typical Elevation View showing UVGI energy placed above heads of room occupants (29)

Even if space is ventilated and has duct

mounted UVC, upper-air UVC could provide a “one-two- punch” where floating viruses that remain uncaptured by the HVAC system are inactivated before they can fall into the occupied zone. Ventilation patterns (natural and mechanical) should promote good air mixing in a space equipped with UVC so that infectious microorganisms are drawn through the UVC “ kill zone .”