CHEYENNE, Wyo. (AP) — Wyoming's governor has implemented temporary, emergency rules to help ensure that truck drivers can deliver propane on time.

The rules signed Monday will be in effect for 20 days and suspend regulations that limit how many hours truck drivers are allowed on the road.

State officials say propane delivery drivers still aren't allowed on the road when they're tired.

Cold weather has driven up demand for propane, which many people use for heating.