Electric fans promote cooling through convection (heat transfer to a fluid, in this case air) and evaporation (heat transferred into the process of water vaporization). Fans are effective at reducing heat stress and promoting thermal comfort, though there is no evidence regarding their effectiveness specific to preventing unplanned health care visits, hospitalization, or death. Fans are more effective for healthy younger adults and people who sweat normally and are not recommended as a cooling strategy for elders on common medications above 37°C (99°F). Fans are relatively inexpensive to obtain and operate, are widely available, and provide immediate relief when operated. There is no evidence regarding implementation of fan distribution programs. Fans should not be used as a sole cooling strategy at high temperatures (above 45°C [113°F]) and ideally would be used as part of a suite of individual cooling strategies, many of which are at least as effective.