Despite this variation, the notion of a thermal optimum persist. The American Society of Heating, Refrigeration, and Air-conditioning Engineers (ASHRAE) has published standards for thermal comfort that are used across the country and have been incorporated into many municipal and state building codes. There is an underlying assumption that the best thermal environment never needs to be noticed and that once an objectively”comfortable” thermal environment has benn provided, all of our thermal needs will have been met. The use of all of our extremely sophisticated environmental control systems is directed to this one end-to produce standard comfort zone conditions.