While heating companies in many European and Nordic countries have long used meters to measure how much heat is used to warm buildings, upon the conversion to private home ownership, Chinese residents did not use nor did utility companies require the use of such measurement devices. Fees have generally been charged based on occupied square meters. In recent years, due to higher energy costs, the use of heat meters became compulsory in some Chinese cities. Meters indicate heat in legal heat units and the calibration of such meters in many countries is regulated by government agencies and subject to local or national guidelines.
