Magma Copper Co.
Superior Div.
Superior, AZ
Notable for: first air-conditioned mine in North America
Plaque location, if specific:
mounted on wall in old office bldg
More about . . .
The warm rock formation at the Magma Copper Company Mines created a need that brought about the first air-conditioned mine in North America, improving health and safety factors in mine operations and making deeper excavation possible. The very first units had been built by Willis H. Carrier in South Africa and then Brazil some years earlier.
With the rock temperature standing at 101 F at the 3,600-foot level, short work shifts were necessary, requiring the constant transport of workers in and out of the torrid mine shafts. Several centrifugal refrigeration machines of 140-ton capacities were lowered through shaft compartments and set to work, lowering the temperature in six weeks to better conditions than could be achieved with traditional ventilating fans after three years. After the area was mined out, the two original units were abandoned and remain in the mine.
Ceremony Notes: May 1976
Comments from Visitors/Members: Plaque is presently displayed in a prominent place at or near the actual equipment. I visited the Magma Copper Co. mine office where the plaque was displayed. This is the same office where the actual ceremony took place in 1976. The office building itself is now run down somewhat from the freshly painted building with a manicured lawn that I remember from 1976, but the plaque is obviously something they are still proud of. It is on the wall in the main entry to the office. The clerk I talked with assured me that the plaque would be relocated to their new office in Superior if the old office building was closed. - V. Webb Etheridge, June 1992.
Image: Copyright authorization is limited to the promotion of the ASME landmarks program, in most cases, and therefore permission to use this image is restricted. An ASME Historic Mechanical Engineering Landmark
* Indicates that item has survived, but is not on display | 
