I. Authority The authority for the State of Colorado, Transportation Commission to adopt these rules is contained in C.R.S. Section 42-4-106(5)(1996) and Section 43-1-106(8)(j) and (k)(1991). The Statement of Basis, Specific Statutory Authority, and Purpose for the September 6, 1996 rulemaking hearing to adopt The Rules is available by contacting Staff Maintenance Branch, Colorado Department of Transportation.

II. Purpose The general purpose of The Rules is to describe the travel conditions, types of vehicles, and the locations which require tire chains, snow tires, four wheel drive or other means to provide adequate traction, when the Department determines such means are necessary to protect the safety of the travelling public and to minimize the occurrence of road closures.

III. Applicability The Rules apply to all state highways on the State Highway System as defined in C.R.S. Section 43-2- 101(1)(1993) or as determined by the State Transportation Commission. IV. Definitions The following definitions shall apply to terms used in The Rules. 1. Adequate tires shall mean tires with conventional tread with a minimum tread depth of 1/8 inch. 2. Alternative Traction Device (ATD) shall mean drive wheel sanders, pneumatically driven chains which, when engaged, spin under the drive wheels automatically as traction is lost or a traction device differing from metal chains in construction, material or design but capable of providing traction equal to or exceeding that of such metal chains under similar conditions. 3. Bare Pavement shall mean pavement that is free of any ice or snow or the center line or lane line of the road is visible.

4. Chain Law shall mean a restriction of travel, due to adverse road, weather or driving conditions, for all or certain vehicles unless the vehicle is equipped with snow tires, tire chains, ATD's, or four wheel drive vehicles with adequate tires with all four wheels engaged as required under the code in effect.

5. Code 15 shall mean an implementation of the chain law which restricts all motor vehicles from travel on the state highway unless the vehicle has snow tires or is equipped with tire chains or ATD's or is a four wheel drive vehicle with adequate tires and all four wheels engaged. 6. Code 16 shall mean an implementation of the chain law which requires the use of chains or ATD's by all vehicles. Under this code, autotransports shall be restricted from travel unless able to use chains or ATD's.

6. Code 17 shall mean an implementation of the chain law that requires all single drive axle CV's in combination meeting the definition 8(a) below be equipped with tire chains or ATD's. All other CV's shall be required to be equipped with tire chains, ATD's or snow tires. 7. Code 18 shall mean an implementation of the chain law that requires all CV's be equipped with tire chains or ATD's.

8. Commercial Vehicle (CV) shall mean a motor vehicle or combination of motor vehicles used in commerce to transport passengers or property if the motor vehicle (a) has a gross combination weight rating of 26,001 pounds or more inclusive of a towed unit with a gross vehicle weight rating of more than 10,000 pounds; or (b) has a gross vehicle weight rating of 26,001 or more pounds; or (c) is designed to transport 16 or more passengers, including the driver. 9. Department shall mean the Colorado Department of Transportation. 10. Motor Vehicle shall mean the same as defined in C.R.S. Section 42-1-102(58)(Cum. Supp. 1995). 11. Snow tires shall mean the same as defined in C.R.S. Section 42-4-106(5)(1996). 12. Tire chains shall mean the same as described C.R.S. Section 42-4-106(5)(a)(I)(1996). 13. Tire cables shall mean a traction device that is made of steel cable as opposed to steel chain link. V. General Provisions 1. Any Department maintenance supervisor or his or her designee shall have the authority to implement the chain law. It is within the discretion of the maintenance supervisor or this designee to determine when road, weather and driving conditions, in accordance with the rules, are such that require the chain law to be in effect. Chain law codes may be implemented concurrently. 2. No person shall operate any motor vehicle on any portion of a state highway that has the chain law implemented without the required tire chains, snow tires, ATD's or four wheel drive vehicles with all four tires engaged as required by the code in effect. Any person who violates The Rules shall be subject to penalty as set forth in C.R.S. Section 42-4-1701(1996). 3. The Department shall place a sign, either electronic or regulatory as described in the Manual of Uniform Traffic Control Devices, notifying vehicles when the chain law is implemented and which code of the chain law is in effect.

4. The Department shall designate chain inspection stations. The purpose of these stations is to provide adequate space for the installation of chains. All vehicles subject to the chain law code applicable at the time may be subject to inspection by Department personnel or appropriate law enforcement personnel for compliance with the chain law before proceeding from the chain inspection station. At the discretion of law enforcement or CDOT personnel, vehicles found to be in non-compliance with the chain law may 1) be held in the inspection area, 2) be required to reverse their direction of travel, or 3) be required to retain a private towing service to convey them through the area covered by the chain law implementation.

5. In the event the chain law is required at a location where the pavement is bare, vehicles laden with flammable, combustible or explosive materials as identified in 49 CFR 172.101 shall have the option of installing chains where the pavement is covered by snow or ice at a safe location outside the travelled portion of the highway.

6. Department personnel or appropriate law enforcement personnel may control the reentry of vehicles from the chain inspection station to the state highway in such a manner as to enhance the flow of traffic and assure the safety of the travelling public. 7. ATD's will be acceptable for operation in an area with a chain law code restriction. Tire cables are not an acceptable ATD on CV's. Tire cables are acceptable on all other motor vehicles. 8. The chain law shall cease to be in effect where designated by a sign or when bare pavement is encountered on a descending grade.

VI. Code Requirements 1. Chain Law Code 17 may be implemented any time there is snow cover on any part of the travelled portion of the pavement on an ascending grade.

2. Chain Law Code 18 may be implemented any time there is snow cover on the entire part of the travelled portion of the pavement on an ascending grade or when in the discretion of the maintenance supervisor or designee, road, weather or driving conditions indicate this restriction is necessary to protect the safety of the travelling public or minimize the occurrence of road closures.

3. Chain Law Code 15 may be implemented any time Chain Law Code 18 is in effect and any motor vehicle, other than a CV, is experiencing traction difficulties on an ascending grade. Code 15 may also be implemented on any other road, any time traction difficulties are occurring with any vehicles.

4. Chain Law Code 16 may be implemented any time Chain Law Code 15 is in effect and any motor vehicles are experiencing traction difficulties.

5. Whenever any code of the chain law is in effect, CV's shall be restricted to the right lane unless encountering a stalled or slower moving vehicle that would result in the loss of traction, in which case the CV may utilize the left or center lane to pass if the movement can be made with safety and without interfering with other traffic. However the pass must be completed without losing traction and the CV must return immediately to the right lane upon completion of the pass. VII. Exemptions 1. Autotransport carriers shall be exempt from using tire chains on all four drive wheels in the event the tire chains would jeopardize the safety of the hydraulic lines of the vehicle. When Code 15 has been implemented and autotransports cannot use tire chains or ATD'S, use of adequate snow tires shall be required. To the extent tire chains do not interfere with the hydraulic lines, autotransport carriers shall be subject to The Rules.

2. Government owned highway maintenance vehicles, in the exercise of highway maintenance activities, shall be exempt from the travel restrictions in The Rules. 3. Vehicle recovery units that are in the exercise of clearing travel lanes in a chain law enforcement area shall be exempt from The Rules.

4. Emergency Response Vehicles shall be exempt from The Rules.