Here is a quick run-down on the types of bulbs used in UV, Accelerated weathering tests.
There are many different spectral irradiances of UV bulbs. Generally speaking:
500 hours under UV-B bulbs = 1 year of South Florida exposure
1000 hours under UV-A bulbs = 1 year South Florida exposure
1000 hours under Xenon Arc = 1 year South Florida exposure
There are additional UV exposure categories for an Arizona climate. (Dry, more intense UV & heat )