(1) Are there any weight exemptions for natural gas engines or electric battery vehicles?

Yes, for the interstate system and no more than one mile access to and from the interstate system, natural gas vehicles or electric battery vehicles, if operated by an engine fueled primarily by natural gas or electric batteries, may exceed vehicle weight limits set in RCW 46.44.041 up to 2,000 pounds with a maximum gross vehicle weight of 82,000 pounds. The increase in weight shall equal the difference between:

(a) The weight of the vehicle attributable to the natural gas tank and fueling system carried by that vehicle; and

(b) The weight of a comparable diesel tank and fueling system.

(2) What weights are authorized for emergency vehicles to travel on the interstate system?

(a) Emergency vehicles may operate without a permit on the interstate system and no more than one mile to and from the interstate system to a maximum gross vehicle weight of 86,000 pounds and axle weights of:

(i) Twenty-four thousand pounds on a single steering axle;

(ii) Thirty-three thousand five hundred pounds on a single drive axle;

(iii) Sixty-two thousand pounds on a tandem axle; or

(iv) Fifty-two thousand pounds on a tandem rear drive steer axle.

(b) In this section, the term emergency vehicle means a vehicle designed to be used under emergency conditions:

(i) To transport personnel and equipment; and

(ii) To support the suppression of fires and mitigation of other hazardous situations.

(c) Operators of emergency vehicles described in this section shall check their route on Washington state department of transportation, commercial vehicle services website for restrictions prior to travel. These vehicles shall obtain approval/permit from the local jurisdiction when traveling on any local roads. Any firefighting apparatus or emergency vehicle shall obtain a permit from commercial vehicles services office prior to traveling on state highways that are not part of the interstate system if their weights exceed what is prescribed in RCW 46.44.190(4).

(3) Can liquid bulk milk be treated as a nondivisible load? Per the Fixing America's Transportation Act (FAST Act), a vehicle carrying fluid milk products shall be considered a load that cannot be easily dismantled or divided (nondivisible). Carriers may obtain annual permits up to 129,000 lbs., and up to 85 ft. of load length when using a double trailer combination. For this section, a double trailer is a tractor, semi-trailer and a second semi-trailer. This section applies to a vehicle that transports raw milk from a farm and/or raw milk products to or from a milk plant, receiving station or transfer station. Transporters of liquid bulk milk are exempt from holiday and commuter curfew restrictions when operating under a permit.

(a) Annual double trailer milk permits cannot exceed legal axle weight per RCW 46.44.041;

(b) Cannot exceed a load length of 85 ft.; and

(c) Must adhere to posted limits and restrictions on WSDOT's commercial vehicle services website.