Urban Airshed Model® (UAM®)
modeling system, developed and maintained by Systems Applications International
(SAI), is the most widely used photochemical air quality model in the world
today. Since SAI's pioneering efforts in photochemical air quality modeling
in the early 1970s, the model has undergone nearly continuous cycles of
application, performance evaluation, update, extension, and improvement.
Other photochemical models have been developed during this long period,
but no model today is more reliable or technically superior.
is a wholly-owned subsidiary of