Chain Up Tips for Passenger & Small Commercial Vehicles

A chain law restriction for vehicles weighing less than 16,001 lbs. including passenger vehicles, crossovers, SUVs, and small trucks can be put into effect in Colorado at any time when weather conditions are severe, primarily on roadways with significant ascending and descending grades. This restriction is Code 15.

It’s quick and easy to test. Insert a quarter upside down into your tire tread (with George Washington’s head first). If the top of the head is covered by tread, you’re good to go. If the top of his head is visible at any point around the tire (test multiple points), you can’t drive when Code 15 of the chain law is in effect. You also likely need new tires.

Stay Informed
When the chain law is in effect, drivers will be notified by the following means: electronic message signs; 511 traveler information;; and media outlets. To stay informed about road conditions, road closures and the chain law, sign up for our email and text message alerts.

Printable version of Chain Up Tips for Smaller Commercial & Passenger Vehicles (pdf)

Snow Plows

During spring, winter, and fall you will often see CDOT’s large orange snowplow trucks clearing roadways to help make your drive much safer. In return, you can help them in the following ways.

  • Don't crowd the plow. Give them space to work. 
  • Don't tailgate.
  • Avoid driving alongside the plow. Because of the height and length of the vehicle, a plow driver’s field of vision is limited. You may not be in the plow driver’s field of vision and the driver may not know you are there.

  • Never pass a snowplow on the right. You will be caught in hard snow, ice, and rock thrown up by the plow blade.

  • If you must pass a snowplow, do so on the left. Allow plenty of distance.

Move to Shoulder

Colorado’s “Move It” law requires motorists involved in minor accidents to move your vehicle immediately out of traffic to a safe location:

  • When the vehicle is driveable;
  • When no drugs or alcohol are involved; and
  • When there are no injuries.

Did You Know

Traffic accidents, rather than volume, account for up to 60% of all traffic delays. A minor accident that takes just 10 minutes to clear can delay traffic by up to one hour. A one-lane blockage on a three-lane freeway reduces the highway’s capacity by more than 50%.


  • Clear snow and ice from all windows and lights
  • Make sure you have a full supply of windshield deicer fluid 
  • Carry an emergency kit that includes an ice scraper/snow brush; cat litter or traction sand; blankets, food and water; flares; first aid kit; extra warm clothing; snow shovel; and alternate traction devices or chains.

If you become stranded, the safest place to be is in your vehicle until help arrives. Be sure you have adequate ventilation and that the vehicle exhaust is unobstructed.


There is no chain or traction device carry requirement for vehicles under 26,001 lbs. anywhere in Colorado in any season. However, if Code 15 of the chain law is put into effect, the fine for driving without proper tires or traction devices in use is $100 plus a $33 surcharge. The fine for not having the proper tires or traction devices in use
and subsequently blocking traffic is $500 plus a $157 surcharge.