when did they change the wind chill formula
Wind chill In November 2001, Canada, the United States, and the United Kingdom implemented a new wind chill index developed by scientists and medical experts on the Joint Action Group for Temperature Indices (JAG/TI).[5][6][7] It is determined by iterating a model of skin temperature under various wind speeds and temperatures using standard engineering correlations of wind speed and heat transfer rate. Heat transfer was calculated for a bare face in wind, facing the wind, while walking into it at 1.4 metres per second (5.0Â km/h). The model corrects the officially measured wind speed to the wind speed at face height, assuming the person is in an open field.[8] The results of this model may be approximated, to within one degree, from the following formula:
Convection heater The Model “S”, here as illustrated in 1924, is an example of an early model convection space heater, by the Sala Heater & Mantel Co. in Dallas, Texas. The Model "S" was considered to be highly efficient radiant type of gas heater at the time. The heater utilizes radiant heat, and, by virtue of draft construction, supplements its power by drawing cold air through the facing, heating it and forcing it into the room through the register. This not only forces the circulation that provides an even warmth in every section of the room, but enables the heater to operate at all times with a perfectly cool exterior. Positive circulation provides an even warmth throughout the room, and guarantees a clean, humid, healthful[citation needed] air to occupants.