SACRAMENTO, CA -- The state of California sent a stern message to semiconductor chip manufacturers yesterday by enacting mandatory rules controlling greenhouse gases.

The new rules would cover a reported 85 plants and require most chip makers to cut releases of sulfur hexafluoride and other fluorinated gases by more than half over the next three years. The plants are those identified as having released at least trace amounts of the gases.

While 85 companies in all are said to be affected, 57 need only comply with the reporting requirements because they amounts they release are so low. The rest -- 28 in all -- account for a reported 94% of fluorinated gas emissions. A reported 12 already comply, however, and the rest need to spend an estimated $37 million in total to bring their plants into compliance.