RPM is the acronym used for revolutions per minute. It measures the number of revolutions completed in one minute around a fixed axis, giving the speed of a mechanical component. It is commonly used to describe the performance of automobile engines.
Like most ballparks built from the 1990s onward, Safeco Field is a 'retro-modern' style ballpark that incorporates many of the features of ballparks built in the 1950s and earlier with modern amenities.
Safeco Field Footnotes - Facts & Figures. 1  Construction cost: $517.6 million (NBBJ) 2  The most expensive single-use stadium in North America. 3  Construction began on March 8, 1997 and the first game was on July 15, 1999.  Owned by the Washington/King County Stadium Authority.