  Angular sky exposure is presented for a number of published BATSE gamma-ray
burst catalogs. A new algorithm was required due to telemetry gaps resulting
from onboard tape recorder failures; the new algorithm improves the 1B Catalog
exposure calculation. The most influential effects limiting BATSE's exposure
are (1) deadtime due to triggering, (2) sky blockage by the Earth, and (3)
trigger disabling when the spacecraft is in the SAA and over other specific
Earth locations. Exposure has improved during the CGRO mission as a result of
decreased Solar flares and magnetospheric particle events.
