Herbert planned to sign an executive order Thursday on the hood of a pickup at the state agency complex off North Temple Street, where some of the state's 7,300 fleet vehicles are kept.
The executive order limits idling to 30 seconds except for vehicles in traffic. Herbert says he will call on all Utah motorists to follow suit and reduce emissions.
Herbert previously announced Utah will buy 73 electric-gas hybrids this year, boosting the total number of hybrids in the state fleet to more than 500. In addition, the state is adding four compressed natural gas vehicles to 85 already in the fleet. And officials are buying two all-electric vehicles.
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