The state of California is attempting to put limits on the amounts of greenhouse gasses emitted by diesel powered off-road vehicles, including earth movers. The move is part of efforts to both improve air quality in general and reduce greenhouse gas emissions.

As might be expected there is opposition to the new plans, particularly from the construction industry which uses a lot of diesel power.

The proposed criteria match new Federal legislation in the United States. But unlike that legislation they apply to existing vehicles as well as to new ones.

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