Big Ass Fans
Big Ass Fans entered the commercial business market in 2008, debuting a line of fans ranging from to in diameter. The following year, it began manufacturing fans in sizes suitable for residential settings. In late 2011, Big Ass Fans acquired a manufacturer of energy efficient residential fans. Haiku models incorporate direct current, permanent magnetics and aerodynamic airfoils making them 80% more efficient than conventional ceiling fans. They held the top 10 spots on Energy Star's Most Efficient 2014 list. In 2014, the company added smart technology SenseME to the Haiku ceiling fan. Haiku with SenseME integrates with the Nest Learning Thermostat through a smartphone app.
Fan death
Air movement will increase sweat evaporation, which cools the body. But in extreme heat – when the blown air is warmer than the body's temperature – it will increase the heat stress placed on the body, potentially speeding the onset of heat exhaustion and other detrimental conditions. The American Environmental Protection Agency (EPA) discourages people from using fans in closed rooms without ventilation when the heat index is above . The EPA does, however, approve of using a fan if a window is open and it is cooler outside, or when the heat index in a closed room is lower.