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Federal regulations
Washington has adopted Part 393 of the Federal Regulations.
Applicability
Part 393 applies to vehicles with a gross vehicle weight rating or gross combination weight rating or gross weight or gross combination weight of 10,001 or more pounds and vehicles transporting hazardous materials requiring placards.
Backup alert devices
A backup alert device or rear crossview mirrors must be mounted on a truck with a cube-style, walk-in cargo box up to 18 feet long.
The backup alert device must warn the driver of the detection of a person or object at a minimum of six feet to the rear of the vehicle and also encompass the width of the rear of the vehicle. A backup alert device is defined as any motion detection device, laser device, camera, or television device.
Rear crossview mirrors are any type of mirrors which, when mounted, will allow the driver to view a minimum distance of six feet to the rear and encompass the width of the rear of the vehicle in order to be able to detect an object or person. The crossview mirrors must be installed in a manner that will satisfy these requirements.
First aid kit
No requirements.
Mudflaps
All motor vehicles, trailers, cargo extensions, and semitrailers shall be equipped with fenders, covers, flaps, or splash aprons adequate for minimizing the spray or splash of water or mud from the roadway to the rear of the vehicle. All devices must be as wide as the tires behind which they are mounted and extending downward to at least the center of the axle.
Mufflers and exhaust systems
All motor vehicles must be equipped with a muffler in good working order and in operation at all times. The system should prevent excessive or unusual noise and smoke. Muffler cutouts, bypasses or similar devices are illegal in highway operations.
Studded tires
No tire may have blocks, flanges, cleats, spikes, or any other protuberances of any material other than rubber projecting beyond the tread surface.
Tire chains
Tire chains of reasonable size are allowed when required for safety because of snow, ice, or other conditions tending to cause a vehicle to skid.
When traffic control signs marked “chains required” are posted by the Department of Transportation, a vehicle or combinations of vehicles may not enter the controlled area without having mounted on its tires the appropriate type and number of tire chains.
A minimum of two extra tire chains must be carried on the vehicle in the event that road conditions require the use of more chains or the chains in use are broken or otherwise useless.
On certain routes, from November 1 to April 1, a sufficient number of tire chains must be carried on the vehicle at all times.
Additional information may be accessed via the Washington State Department of Transportation website: https://wsdot.com/travel/real-time/mountainpasses/tiresandchains.