54/Plumbing Engineer August 2021
sensor-operated products. With this technology, there is minimal use of batteries and the need for facility staff to spend time and effort replacing batteries is significantly lower. Hard-wired fittings and fixtures are considered the most sustainable option because they minimize the use and disposal of batteries. It's important to note that in order to ensure compli- ance with OSHPOD and FGI guidelines mandating the ability to function during a power loss, these devices should be specified with battery backup capability. Most high-quality, sensor-operated fittings and fixtures include this feature built into them. With a loss of power, these units will function nor- mally until power returns to the facility. This feature is highly recommended in areas prone to seismic activity and severe weather that can potentially interrupt power supplies. To avoid the cost and complexity of installing hard- wired power supplies to each fixture and fitting in a facil- ity, it is common to use battery-powered sensor devices. This is particularly true in existing facilities that are being upgraded from manual to sensor operation that do not wish to complicate a project by installing hard-wired power supplies. The benefits of using just batteries alone are a reduc- tion in project cost and the time required for project completion. Unfortunately, this is the least sustainable power solution over time because of ongoing battery replacement and disposal. Time and money saved during the installation phase do not translate into a lower total cost of ownership over time for the facility - particu- larly when the time and labor needed to replace batteries are considered. When a facility has no option to install hard-wired, sensor-operated products and must rely upon battery power, two hybrid power-generating technologies are designed to generate their own power onsite and, there- fore, extend the life of batteries. These hybrid power solutions come as optional features on battery-powered devices and include solar cells and miniaturized hydro- electric turbines. Solar-powered units collect natural and artificial light as the energy source from a built-in solar cell. The cell converts ambient light into usable energy that the device will use to avoid expending battery power whenever pos- sible, extending and potentially doubling the life of the batteries. If a facility has poor water quality with higher levels of hardness, sediment, turbidity or iron, the selec- tion of a solar cell is desirable because it has no moving parts that are in contact with the water supply. While solar cells are very efficient and can operate under low light conditions and in conjunction with occu- pancy sensors, they will supply only a fixed amount of hybrid power regardless of the frequency of use. In very high-use scenarios - such as airports, stadiums, concert halls and large schools - the use of turbines might be the best hybrid power choice. Touch-free, sensor-operated devices with turbines use the pressure and flow of the water to create hybrid energy, much like the turbines in a hydroelectric dam, device. Handwashing and scrub sink fixtures shall not be equipped with wrist or elbow blades but shall be equipped with sensor controls or controls that do not involve contact with the upper extremities. The Facility Guidelines Institute's (FGI) "Guidelines for Design and Construction of Hospitals and Outpatient Facilities" recommends handwashing station sinks used by medical and nursing staff, patients, the public and food handlers shall have fittings that can be operated without using hands. Single-lever or wrist blade devices are permitted on handwashing stations - the blades shall be at least 4 inches in length and the location and arrangement of the fittings shall provide proper clear- ance for operation of blade type handles. Sensor-regulated water fixtures shall meet user needs for temperature and length of time the water flows and be capable of functioning during loss of normal power. The use of sensor-regulated faucets with manual temperature control shall be permitted. Freestanding scrub sinks shall be trimmed with foot, knee or electronic sensor controls. Note that the term "hands-free" does not refer to faucets operated using wrist blades or single-lever faucets. Public Health Ontario's "Best Practices for Hand Hygiene in All Health Care Settings" recommends con- trols (faucets) shall be hands-free. Electric eye operation or foot-, elbow- or knee-operated handles/blades are acceptable. Faucets shall not swivel or be fitted with aerators or similar aspirating devices. The U.S. Department of Homeland Security, Science and Technology Directorate's "Desk Reference for COVID Recovery and Future Pandemic Preparation" recommends touchless fixtures (e.g., faucets, trash cans) and self-cleaning bathrooms in its list of material inter- ventions in built environments. Manual Vs. Automatic Sensor Operation Prior to the COVID pandemic, many facilities had begun the transition to touch-free sensor fittings and fittings operation to conserve water and prevent run- ons. Codes and standards such as Cal-Green, California Energy Commission and Leadership in Energy and Environmental Design made water conservation and sustainability a primary objective in most commercial facilities; sensor-operated devices supported them. In some facilities, touch-free operation was viewed as a method for reducing normal wear-and-tear and vandal- ism. The same touch-free aspect was highlighted during the pandemic and led to a surge in replacements and retrofits from manual to automatic sensor operation. Automatic sensor-operated fittings and fixtures always require a power supply, be it battery, solar cells, minia- turized turbines or a connection to the building electrical grid. The use of power supplies has permitted the devel- opment of several features that simply cannot be added to manually operated products. Some of these enhance- ments include functions that can help reduce waterborne pathogens in ways that can improve outcomes and mini- mize risk. Hard-wired technology uses the building electri- cal system as the energy source to operate touch-free,
Touchless
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