The Senate Labor and Human Resources Committee yesterday approved, 12 to 4, a bill authorizing $1.8 billion over the next 2 1/2 years for health insurance for the unemployed.

The compromise bill, sponsored by Sen. Dan Quayle (R-Ind.) and backed by Committee Chairman Orrin G. Hatch (R-Utah) and senior committee Democrat Edward M. Kennedy (D-Mass.), was endorsed by four Republicans and eight Democrats. Four other Republicans opposed it.

It authorizes $200 million in fiscal 1983, $900 million in fiscal 1984 and $700 million in fiscal 1985 for grants to the states for health care for the unemployed. States with high unemployment would get the largest shares of the money. The states would be required to provide a minimum level of benefits.

They could charge patients up to 7.5 percent of their weekly unemployment checks as premiums. The administration took no formal position on the measure, according to Quayle aides, though it had threatened veto on more generous House versions.

Kennedy tried but failed on an 8-to-8 vote to lift the authorizations to the levels allowed in the compromise House-Senate budget resolution now pending--$350 million in fiscal 1983, $2 billion in fiscal 1984 and $1.65 billion in fiscal 1985.

The House Energy and Commerce Committee reported a similar bill May 24, but with larger authorizations beginning at $2.7 billion a year. This bill hasn't reached the House floor. Senate Finance Committee Chairman Robert J. Dole (R-Kan.) has a bill of his own awaiting Finance Committee action.