All vehicles over 10,000 pounds GVW shall carry a minimum of 2 extra chains for use in the event that road conditions require the use of more chains or that chains in use are broken or otherwise made useless, WAC 204-24-050 (2) (f).
Approved chains for vehicles over 10,000 pounds gross vehicle weight shall have at least two side chains attached sufficient cross chains of hardened metal so that at least one cross-chain is in contact with the road surface at all times. Plastic chains shall not be allowed. The Washington State Patrol may approve other devices as chains if the devices are equivalent to regular chains in performance (cable chains allowable).
On the following routes, all vehicles and combinations of vehicles over 10,000 pounds shall carry sufficient tire chains to meet the requirements from November 1 to April 1 of each year or at other times when chains are required for such vehicles:
Vehicles making local deliveries as indicated on bills of lading and not crossing the mountain pass are exempt from this requirement if operating outside of the chain required area.
The Washington State Department of Transportation or Washington State Patrol may prohibit any vehicle from entering a chain/approved traction tire control area when it is determined that the vehicle will experience difficulty in safely traveling the area.
Movement by permit on mountain passes is prohibited where any of the following signs are displayed: