1.   Any such expansion of pollution rules would probably require action by Congress, where there is significant opposition to the idea.

2.   As long as they have that classification, they are not subject to any pollution rules.

3.   At the same time, the White House is considering a recommendation by Whitman and Energy Secretary Spencer Abraham to relax pollution rules.

4.   Both candidates for the Democratic nomination, Vice President Al Gore and former Sen. Bill Bradley, have long advocated tighter auto pollution rules.

5.   All sides in the debate agree that companies should be encouraged to audit themselves to confirm that they are complying with pollution rules and to minimize waste in manufacturing.

6.   Clinton tried to find a compromise between EPA and his economic advisers, who were more skeptical of the pollution rules.

7.   Environmentalists also warn that converting to diesels will limit opportunities to tighten pollution rules even further someday.

8.   Officials are especially concerned about state laws protecting companies from disclosure or punishment when they voluntarily report violations of pollution rules.

9.   Otherwise, the Democrats say, US employers would move jobs overseas to take advantage of cheap labor and lax pollution rules.

10.   Partly to meet stricter pollution rules, automakers are offering small numbers of cars and trucks that are less dependent of petroleum fuel.