A thermostatic mixing valve (TMV) does the same thing as a standard tempering valve. It keeps the hot water supply below scalding temperatures. But thermostatic mixing valves have a quicker response to pressure variations and temperature changes. As they are more sensitive and reliable, TMVs have to be put in at places like primary and secondary schools, child care centres and nursing homes where they are set at a lower temperature of 45°C. As such, they offer a safer option for people in these environments using heated water for personal hygiene purposes.