Occupants have a direct impact on water use and are key to a building’s water conservation program. Significant water can be wasted from occupants inadvertently leaving water fixtures running or not correctly using water-efficient plumbing and kitchen equipment. A conventional kitchen water faucet kept open at fifty percent for only a quarter of an hour wastes nearly ten gallons of water. Conversely, occupants that are well educated on the benefits and proper use of all directly-contacted water system components can ensure that water reductions are realized from water efficiency retrofits. For example, occupants should be trained on the use of dual-flush toilets. Occupants can also be incentivized through contests or award programs to assist with environmentally conscious practices.

Leaks in the water system, if left unidentified and untreated, can serve as a catalyst for mold growth within the building space. Prolonged exposure to molds may result in negative health effects such as eye, throat, or skin irritations as well as respiratory problems. Installing sunlight covers on cooling towers and other external water components helps inhibit algae growth, while meticulous metering and monitoring of water use assists in identifying leaks.

If utilizing non-potable water resources on-site, human health must be considered and protected. State and local regulations and permit requirements should be followed during installation and throughout operations. Regular maintenance of greywater and stormwater harvesting systems will ensure proper water reuse without exposing humans to potentially negative health effects from direct interaction. Improve water quality whenever possible; for example with additional filtration or water softening as needed.

Water, sometimes coupled with suppressant foam, is used to subdue fires in the event of an emergency by distribution of a fire sprinkler system. The sprinklers become active when ambient temperatures near the sprinkler head reach a designated level and as a result promote human safety. Fire safety sprinklers use roughly ten times less water than would be needed by a fire department.