TITLE 31 - MOTOR VEHICLES

ARTICLE 9 - EQUIPMENT

31-5-901. General requirements; applicability of provisions.

(a) It is a misdemeanor for any person to drive or move or for the owner to cause or knowingly permit to be driven or moved on any highway any vehicle or combination of vehicles which is in such unsafe condition as to endanger any person, or which does not contain those parts or is not at all times equipped with such lamps and other equipment in proper condition and adjustment as required in this act, or which is equipped in any manner in violation of this act, or for any person to do any act forbidden or fail to perform any act required under this act.

(b) Nothing contained in this act shall prohibit equipment required by the United States Department of Transportation nor the use of additional parts and accessories on any vehicle not inconsistent with the provisions of this act.

(c) The provisions of W.S. 31-5-901 through 31-5-970 and regulations of the superintendent with respect to equipment required on vehicles shall not apply to vehicles moved solely by human power, motorcycles, motor-driven cycles, mopeds, multipurpose vehicles, implements of husbandry, highway construction machinery or farm tractors except as specifically made applicable.

(d) A federal motor vehicle safety standard which conflicts with a provision of this act shall supersede that provision as to any vehicle in compliance with the federal standard. The highway department shall report any conflict to the legislature and the superintendent may adopt a regulation to replace the superseded provision.

31-5-910. Lighted lamps and illuminating devices.

Every vehicle including those listed in W.S. 31-5-901(c), except as otherwise provided in this act, upon a highway within this state at any time from one-half (1/2) hour after sunset to one-half (1/2) hour before sunrise and at any other time when, due to insufficient light or unfavorable atmospheric conditions, persons and vehicles on the highway are not clearly discernible at a distance of one thousand (1,000) feet ahead shall display lighted head and other lamps and illuminating devices as respectively required for different classes of vehicles, subject to exceptions with respect to parked vehicles. Stop lights, turn signals and other signaling devices shall be lighted as prescribed for those devices.

31-5-911. Visibility distance.

Whenever a requirement is declared by this act as to distance from which certain lamps and devices shall render objects visible or within which the lamps or devices shall be visible, the provisions apply during the times stated in W.S. 31-5-910 in respect to a vehicle without load when upon a straight, level, unlighted highway under normal atmospheric conditions unless a different time or condition is expressly stated.

31-5-912. Head lamps.

(a) A motor vehicle, including a multipurpose vehicle which is greater than fifty (50) inches in width, shall be equipped with at least two (2) head lamps with at least one (1) on each side of the front of the motor vehicle, which head lamps comply with the regulations of the superintendent.

(b) A motorcycle, motor-driven cycle, multipurpose vehicle which is fifty (50) inches or less in width or moped shall be equipped with at least one (1) head lamp which shall comply with the regulations of the superintendent.

31-5-913. Tail lamps.

(a) A motor vehicle, multipurpose vehicle which is greater than fifty (50) inches in width, trailer, semitrailer, pole trailer or any other vehicle which is being drawn at the end of a combination of vehicles, shall be equipped with at least two (2) tail lamps mounted on the rear, which shall comply with the regulations of the superintendent. The superintendent may by regulation allow one (1) tail lamp on any vehicle equipped with only one (1) when it was made. A motorcycle, motor-driven cycle, multipurpose vehicle which is fifty (50) inches or less in width or moped shall be equipped with at least one (1) tail lamp which shall comply with the regulations of the superintendent.

(b) Either a tail lamp or a separate lamp shall be so constructed and placed as to illuminate with a white light the rear registration plate of all vehicles listed in subsection (a) of this section. The lamp shall comply with the regulations of the superintendent.

(c) A street rod as defined in W.S. 31-1-101(a)(xv)(N) or a custom vehicle as defined in W.S. 31-1-101(a)(xv)(O) may use blue dot tail lights for stop lamps, rear turning indicator lamps, rear hazard lamps and rear reflectors. For purposes of this subsection, "blue dot tail light" means a red lamp installed in the rear of a motor vehicle containing a blue or purple insert that is not more than one (1) inch in diameter.

NOTE: This section is effective July 1, 2010.

31-5-914. Rear reflectors.

Every motor vehicle, multipurpose vehicle which is greater than fifty (50) inches in width, trailer, semitrailer, pole trailer or other vehicle which is being drawn at the end of a combination of vehicles shall carry on the rear, either as a part of the tail lamps or separately, two (2) or more red reflectors complying with the regulations of the superintendent. Motorcycles, motor-driven cycles, multipurpose vehicles which are fifty (50) inches or less in width or mopeds shall carry on the rear at least one (1) red reflector complying with the regulations of the superintendent.

31-5-915. Stop lamps; electric turn signal lamps.

(a) Every motor vehicle, multipurpose vehicle which is greater than fifty (50) inches in width, trailer, semitrailer, pole trailer or other vehicle which is being drawn at the end of a combination of vehicles shall be equipped with two (2) or more stop lamps complying with the regulations of the superintendent. Every motorcycle, motor-driven cycle, multipurpose vehicle which is fifty (50) inches or less in width or moped shall be equipped with at least one (1) stop lamp complying with the regulations of the superintendent. The superintendent may by regulation allow one (1) stop lamp on any vehicle equipped with only one (1) when it was made.

(b) Every motor vehicle, trailer, semitrailer, pole trailer or other vehicle which is being drawn at the end of a combination of vehicles shall be equipped with electrical flashing turn signals complying with the regulations of the superintendent except that passenger cars and trucks less than eighty (80) inches in width, manufactured or assembled prior to January 1, 1953, need not be equipped with electric turn signal lamps.

31-5-916. Additional lamps and reflectors.

The superintendent by regulation may require trucks, buses, motor homes, motor vehicles with truck-campers, trailers, semitrailers and pole trailers to have additional lamps and reflectors.

31-5-917. Color of lighting devices.

All lighting devices and reflectors mounted on the rear of any vehicle shall display or reflect a red color, except the stop light or other signal device, which may be red or yellow, and except that the light illuminating the license plate shall be white and the light emitted by a backup lamp shall be white.

31-5-918. Vehicles in combination.

Whenever motor vehicles and other vehicles are operated in combination during the time that lights are required, any lamp need not be lighted which, by reason of its location on a vehicle of the combination, would be obscured by another vehicle of the combination.

31-5-919. Lamps, reflectors and flags on projecting loads.

Whenever the load upon any vehicle extends to the rear four (4) feet or more beyond the bed or body of the vehicle there shall be displayed at the extreme rear end of the load, at the times specified in W.S. 31-5-910, two (2) red lamps, two (2) red reflectors located so as to indicate maximum width, and on each side one (1) red lamp located so as to indicate maximum overhang. There shall be displayed at all other times on any vehicle having a load which extends beyond its sides or more than four (4) feet beyond its rear, red or fluorescent orange flags, not less than twelve (12) inches square, marking the extremities of the load, at each point where a lamp would otherwise be required by this section. Lamps and reflectors required in this section shall comply with the regulations of the superintendent.

31-5-920. Parked vehicles.

(a) Every vehicle shall be equipped with one (1) or more parking lamps which shall comply with the regulations of the superintendent.

(b) Whenever a vehicle is lawfully parked upon a street or highway during the hours between one-half (1/2) hour after sunset and one-half (1/2) hour before sunrise and if there is sufficient light to reveal persons and vehicles within a distance of five hundred (500) feet upon the street or highway, no lights need be displayed upon the parked vehicle.

(c) Whenever a vehicle is parked or stopped upon a roadway or adjacent shoulder, whether attended or unattended, during the hours between one-half (1/2) hour after sunset and one-half (1/2) hour before sunrise and there is not sufficient light to reveal any person or object within a distance of five hundred (500) feet upon the highway, the vehicle so parked or stopped shall display parking lamps complying with the requirements of the superintendent.

(d) Any lighted head lamps upon a parked vehicle shall be depressed or dimmed.

31-5-921. Farm and other vehicles and equipment; slow moving vehicle emblems.

(a) Every vehicle, including animal-drawn vehicles and vehicles referred to in W.S. 31-5-901(c) not specifically required by other provisions of this act to be equipped with lamps or other lighting devices, shall at the times specified in W.S. 31-5-910 be equipped with at least one (1) lamp displaying a white light visible from a distance of not less than one thousand (1,000) feet to the front of the vehicle and shall also be equipped with two (2) lamps displaying red light visible from a distance of not less than one thousand (1,000) feet to the rear of the vehicle, or as an alternative, one (1) lamp displaying a red light visible from a distance of not less than one thousand (1,000) feet to the rear and two (2) red reflectors visible from all distances within six hundred (600) feet to the rear when illuminated by the lawful lower beams of head lamps.

(b) Every farm tractor and every self-propelled implement of husbandry manufactured or assembled after January 1, 1974, shall at all times, and every other such motor vehicle shall at all times mentioned in W.S. 31-5-910, be equipped with lamps and reflectors as follows:

(i) At least two (2) head lamps complying with the regulations of the superintendent;

(ii) At least one (1) red lamp visible when lighted from a distance of not less than one thousand (1,000) feet to the rear mounted as far to the left of the center of the vehicle as possible;

(iii) At least two (2) red reflectors visible from all distances within six hundred (600) feet to the rear when directly in front of lawful lower beams of head lamps.

(c) On every combination of farm tractors and towed farm equipment or towed implement of husbandry, the farm tractor shall be equipped as required by subsection (b) of this section, and the towed unit shall at all times mentioned in W.S. 31-5-910 be equipped with lamps and reflectors as follows:

(i) If the towed unit or its load extends more than four (4) feet to the rear of the tractor or obscures any light thereon, the unit shall be equipped on the rear with at least one (1) red lamp visible when lighted from a distance of not less than one thousand (1,000) feet to the rear mounted as far to the left of the center of the towed vehicle as practicable, and at least two (2) red reflectors visible from all distances within six hundred (600) feet to the rear when directly in front of lawful lower beams of head lamps;

(ii) If the towed unit of the combination extends more than four (4) feet to the left of the center line of the tractor, the unit shall be equipped on the front with an amber reflector visible from all distances within six hundred (600) feet to one hundred (100) feet to the front when directly in front of lawful lower beams of head lamps. The reflector shall be so positioned to indicate as nearly as practicable, the extreme left projection of the towed unit.

(d) Every farm tractor and every self-propelled unit of farm equipment or implement of husbandry and special mobile equipment designed for operation at speeds not in excess of twenty-five (25) miles per hour shall at all times be equipped with a slow moving vehicle emblem mounted on the rear except as provided in subsection (e) of this section.

(e) Every combination of farm tractor and towed farm equipment or towed implement of husbandry or units towed by special mobile equipment normally operating at speeds not in excess of twenty-five (25) miles per hour shall at all times be equipped with a slow moving vehicle emblem as follows:

(i) Where the towed unit or any load thereon obscures the slow moving vehicle emblem on the towing unit, the towed unit shall be equipped with a slow moving vehicle emblem. In such cases, the towing vehicle need not display the emblem;

(ii) Where the slow moving vehicle emblem on the towing unit is not obscured by the towed unit or its load, then either or both may be equipped with the required emblem but it shall be sufficient if either has it.

(f) Use of the slow moving vehicle emblem is not required on highway construction and maintenance equipment when the vehicle is operated exclusively within areas guarded by a flagman or clearly visible warning signs.

(g) No person shall use the slow moving vehicle emblem except as required in this section nor display the emblem on a vehicle traveling at a speed in excess of twenty-five (25) miles per hour nor on a stationary object along the highway.

(h) The emblem required in subsections (d) and (e) of this section shall comply with current standards and specifications of the American Society of Agricultural Engineers.

31-5-922. Spot lamps.

Any motor vehicle may be equipped with not to exceed two (2) spot lamps and every lighted spot lamp shall be so aimed and used upon approaching another vehicle that no part of the high-intensity portion of the beam will strike the windshield, or any windows, mirror, or occupant of another vehicle in use.

31-5-923. Vehicular traffic hazard lamps.

(a) Any vehicle including those referred to in W.S. 31-5-901(c) may be equipped with lamps for the purpose of warning the operators of other vehicles of the presence of a vehicular traffic hazard requiring the exercise of unusual care in approaching, overtaking or passing.

(b) After January 1, 1986, every bus, truck, truck tractor, trailer, semitrailer or pole trailer eighty (80) inches or more in over-all width or thirty (30) feet or more in over-all length shall be equipped with lamps complying with the regulations of the superintendent.

31-5-924. Multiple-beam lamps.

(a) Whenever a motor vehicle including those referred to in W.S. 31-5-901(c) if equipped with multiple-beam lamps is being operated on a highway during the times specified in W.S. 31-5-910, the driver shall use a distribution of light, or composite beam, directed high enough and of sufficient intensity to reveal persons and vehicles at a safe distance in advance of the vehicle, subject to the following requirements and limitations:

(i) Whenever a driver of a vehicle approaches an oncoming vehicle, the driver shall, before coming within five hundred (500) feet of the oncoming vehicle use a distribution of light, or composite beam, so aimed that the glaring rays are not projected into the eyes of the oncoming driver. The lowermost distribution of light or composite beam, shall be aimed to avoid glare at all times, regardless of road contour and loading;

(ii) Whenever the driver of a vehicle approaches another vehicle within three hundred (300) feet from the rear, the driver shall use a distribution of light other than the uppermost distribution of light.

31-5-925. Single-beam lamps.

Head lamps which provide only a single distribution of light shall be permitted on all farm tractors regardless of date of manufacture, and on other motor vehicles manufactured and sold prior to July 1, 1956, if the head lamps comply with the regulations of the superintendent.

31-5-926. Alternate lighting for slow-moving vehicles.

Any motor vehicle may be operated under the conditions specified in W.S. 31-5-910 when equipped with two (2) lighted lamps upon the front thereof capable of revealing persons and objects one hundred (100) feet ahead in lieu of head lamps otherwise required under this act if the vehicle is not operated at a speed in excess of twenty (20) miles per hour.

31-5-927. Number of driving lamps.

Whenever a motor vehicle including those referred to in W.S. 31-5-901(c) equipped with head lamps as required in this act is also equipped with any other driving lamps on the front thereof, not more than a total of four (4) of the lamps on the front of a vehicle shall be lighted at any one (1) time when upon a highway. Driving lamps do not include turn or hazard warning signal lamps.

31-5-928. General lighting restrictions; authorized emergency vehicles.

(a) During the times specified in W.S. 31-5-910, any lighted lamp or illuminating device upon a motor vehicle other than head lamps, spot lamps, auxiliary lamps, flashing turn signals, vehicle hazard warning lamps and school bus warning lamps, which projects a beam of light of an intensity greater than three hundred (300) candlepower shall be so directed that no part of the high intensity portion of the beam will strike the level of the roadway on which the vehicle stands at a distance of more than seventy-five (75) feet from the vehicle.

(b) Except as required in W.S. 31-5-929 and this section, no person shall drive or move any vehicle or equipment upon any highway with any lamp or device thereon capable of displaying a red light or blue light visible from directly in front of the center thereof.

(c) Flashing lights are prohibited except as authorized by W.S. 31-5-915, 31-5-921, 31-5-929, 31-5-930, 31-5-931 and this section.

(d) Every authorized emergency vehicle, except police vehicles and as otherwise specified in this subsection, shall, in addition to any other equipment required by law, be equipped with at least one (1) red lamp visible from five hundred (500) feet in front of the vehicle. Except as otherwise provided in this subsection, every authorized emergency vehicle, may be equipped with one (1) or more blue, white or amber lights. Vehicles used by the department to clear snow from public highways may be equipped with one (1) or more lights of a conspicuous color as specified by rules adopted by the department. Privately-owned vehicles used by members of a fire department or emergency service organization in performing or traveling to perform assigned duties in those organizations shall display at least one (1) flashing white, red or amber light, but no blue lights, visible from five hundred (500) feet in front of the vehicle.

(e) A police vehicle primarily engaged in traffic law enforcement shall be marked so as to be readily identifiable.

(f) The following vehicles are authorized to display flashing white and amber lights in addition to those otherwise authorized by law:

(i) Vehicles of civil emergency preparedness agencies;

(ii) Vehicles of municipalities and public service corporations;

(iii) Wreckers;

(iv) Funeral cars.

(g) In addition to these lights otherwise authorized by law, a wrecker is authorized to display flashing red and blue lights at the scene of any emergency.

31-5-929. School buses.

(a) Every school bus shall, in addition to any other equipment and distinctive markings required by this act, be equipped with signal lamps mounted as high and as widely spaced laterally as practicable, which shall display to the front two (2) alternately flashing red lights located at the same level and to the rear two (2) alternately flashing red lights located at the same level, and these lights shall be visible at five hundred (500) feet in normal sunlight.

(b) Any school bus shall, in addition to the lights required by subsection (a) of this section, be equipped with yellow signal lamps mounted near each of the four (4) red lamps and at the same level but closer to the vertical centerline of the bus, which shall display two (2) alternately flashing yellow lights to the front and two (2) alternately flashing yellow lights to the rear, and these lights shall be visible at five hundred (500) feet in normal sunlight. These lights shall be displayed by the school bus at least one hundred (100) feet, but not more than five hundred (500) feet, before every stop at which the alternately flashing red lights required by subsection (a) of this section will be actuated.

(c) The superintendent is authorized to adopt standards and specifications applicable to lighting equipment on and special warning devices to be carried by school buses consistent with this act, but supplemental thereto. The standards and specifications shall correlate with and, so far as possible, conform to the specifications then current as approved by the Society of Automotive Engineers.

31-5-930. Highway construction and maintenance vehicles.

(a) The superintendent shall adopt specifications and rules governing the use of flashing lights on vehicles engaged in highway construction or maintenance operations.

(b) The driver of a vehicle engaged in highway construction or maintenance shall comply with rules adopted under this section.

31-5-931. Backup and side marker lamps.

(a) Any motor vehicle may be equipped with not more than two (2) backup lamps either separately or in combination with other lamps, but any such backup lamp shall not be lighted when the motor vehicle is in forward motion.

(b) Any vehicle may be equipped with one (1) or more side marker lamps and any side marker lamp may be flashed in conjunction with turn or vehicular hazard warning signals.

31-5-932. Approved sale of lighting devices; mounting.

(a) No person shall have for sale, sell or offer for sale for use upon or as a part of the equipment of a motor vehicle, trailer, semitrailer, motorcycle, motor-driven cycle, moped or pole trailer, or use upon the vehicle any head lamp, auxiliary or fog lamp, rear lamp, signal lamp or reflector, which reflector is required by this article, or parts of any of the foregoing which tend to change the original design or performance, unless of a type which has been submitted to the superintendent and approved by him. This section does not apply to equipment in actual use prior to January 1, 1956, or replacement parts therefor.

(b) No person shall have for sale, sell or offer for sale for use upon or as a part of the equipment of a motor vehicle, trailer, semitrailer or pole trailer any lamp or device mentioned in this section which has been approved by the superintendent unless the lamp or device bears thereon the trade-mark or name under which it is approved so as to be legible when installed.

(c) No person shall use upon any motor vehicle, trailer, semitrailer or pole trailer any lamps mentioned in this section unless the lamps are mounted, adjusted and aimed in accordance with instructions of the superintendent.

31-5-933. Repealed by Laws 1985, ch. 138, 3.

31-5-934. Approved sale of equipment generally.

(a) A person shall not sell or offer for sale any lamp, reflector, hydraulic brake fluid, seat belt, safety glass, emergency disablement warning device, studded tire, motorcycle helmet, eye protection device for motorists, or red rear bicycle reflector unless and until it has been approved by the superintendent.

(b) A person shall not sell or offer for sale any item of equipment for which a standard has been adopted under W.S. 31-5-935 unless and until it has been approved by the superintendent.

31-5-935. Standards for safety equipment.

(a) The superintendent shall adopt standards for lamps, reflectors, hydraulic brake fluids, seat belts, safety glass, emergency disablement warning devices, studded tires, motorcyclist helmets, eye protection devices and red rear bicycle reflectors.

(b) The superintendent may adopt standards for safety equipment that comply with standards of the United States Department of Transportation.

(c) Standards adopted by the superintendent may conform with standards issued or endorsed by any recognized organization or agency such as the United States Department of Transportation and other federal agencies, Vehicle Equipment Safety Commission, American National Standards Institute and Society of Automotive Engineers.

31-5-936. Identification requirements for equipment.

Any equipment described in W.S. 31-5-934 or any package containing the equipment shall bear the manufacturer's trade mark or brand name unless it complies with identification requirements of the United States Department of Transportation or other federal agencies.

31-5-937. Approval of safety equipment by superintendent.

(a) The superintendent shall approve or disapprove any lighting device or other safety equipment, component or assembly of a type for which approval is specifically required in this act within a reasonable time after approval has been requested.

(b) The superintendent shall establish the procedure to be followed when request for approval of any lighting device or other safety equipment, component or assembly is submitted under this section. The procedure may provide for submission of the device, component or assembly to the American Association of Motor Vehicle Administrators as the agent of the superintendent and for the issuance of an approval certificate by the association in the name of the superintendent in lieu of submission of the device, component or assembly to the superintendent. Approval issued by the association shall have the same force and effect as if it had been issued by the superintendent.

(c) The superintendent shall maintain and publish lists of all devices, components or assemblies which have been approved by him.

31-5-938. Duration of superintendent's approval.

Approvals shall remain valid unless revoked under W.S. 31-5-939 or unless the superintendent requires them to be renewed under regulations issued by him.

31-5-939. Revocation of superintendent's approval; reapproval.

(a) Whenever the superintendent has reason to believe that a device approved under W.S. 31-5-937 does not comply with his standards, he shall upon thirty (30) days notice to the one to whom the approval was issued conduct a hearing upon the question of the continued compliance of the approved device. After the hearing the superintendent shall determine whether the device meets the requirements of the applicable standard. If the device does not meet those requirements the superintendent shall give notice to the one to whom the approval has been issued of his intention to revoke the approval. If the holder of the approval fails to satisfy the superintendent that the device being sold or offered for sale meets the applicable standard within ten (10) days of the notice, the superintendent shall revoke the approval and shall require the withdrawal of all such devices from the market and may require that all devices sold since the notification be replaced by devices that do comply.

(b) When an approval has been revoked pursuant to this section, the device shall not be again approved unless and until it has been submitted to reapproval and it has been demonstrated, in the same manner as in an application for an original approval, that the device fully meets the requirements of the applicable standard. The superintendent may require that all previously approved items are being effectively recalled and removed from the market as a condition for reapproval.

31-5-940. Testing and enforcement program.

(a) The highway department may purchase and test equipment described in W.S. 31-5-934 to determine whether it complies with its standards.

(b) Upon identification of unapproved or substandard devices being sold or offered for sale, the superintendent shall give notice to the person selling them that he is in violation of W.S. 31-5-934 and that selling or offering them for sale is prohibited.

(c) In order to enforce the prohibition against the sale or offer for sale of unapproved or substandard devices, the superintendent may file a petition in the district court to enjoin any further sale or offer of sale of the unapproved or substandard devices. Upon a prima facie showing that the device is of a type required to be approved by the superintendent, it has not been approved and it is being sold or offered for sale, the injunction shall be issued.

31-5-950. General braking requirements.

(a) Every motor vehicle and every combination of vehicles shall have a service braking system which will stop the vehicle or combination within forty (40) feet from an initial speed of twenty (20) miles per hour on a level, dry, smooth, hard surface or within such shorter distance as may be specified by the superintendent.

(b) Every motor vehicle and combination of vehicles excluding motorcycles, motor-driven cycles and mopeds shall have a parking brake system adequate to hold the vehicle or combination on any grade on which it is operated under all conditions of loading on a surface free from snow, ice or loose material or which shall comply with performance standards issued by the superintendent.

(d) The superintendent may adopt performance requirements for braking systems under this section. In formulating these requirements, the superintendent shall consider standards of the United States Department of Transportation, recommendations of other agencies and organizations, different classes of vehicles, deceleration rates, speeds, weather, loads, terrain and all other factors bearing on safe highway operations.

(e) This section applies to motorcycles, motor-driven cycles, multipurpose vehicles and mopeds unless specifically excluded.

31-5-951. Brakes on motor-driven cycles.

(a) The superintendent may require an inspection of the braking system on any motor-driven cycle and disapprove any brake which in his opinion is not so designed or constructed as to insure reasonable and reliable performance in actual use.

(b) The department may refuse to register or may suspend or revoke the registration of any motor-driven cycle when it is notified by the superintendent that the brake thereon does not comply with the provisions of this section.

(c) No person shall operate on any highway any motor-driven cycle if the superintendent has disapproved the brake equipment upon that motor-driven cycle or type of motor-driven cycle.

31-5-952. Horns and warning devices.

(a) Every motor vehicle when operated upon a highway shall be equipped with a horn in good working order and capable of emitting sound audible under normal conditions from a distance of not less than two hundred (200) feet, but no horn or other warning device shall emit an unreasonably loud or harsh sound or a whistle. The driver of a motor vehicle shall when reasonably necessary to insure safe operation give audible warning with his horn but shall not otherwise use the horn when upon a highway.

(b) No vehicle shall be equipped with nor shall any person use upon a vehicle any siren, whistle or bell, except as otherwise permitted in this section.

(c) Any vehicle may be equipped with a theft alarm signal device which is so arranged that it cannot be used by the driver as an ordinary warning signal. The theft alarm signal device may use a whistle, bell, horn or other audible signal but shall not use a siren.

(d) Every authorized emergency vehicle, except wreckers, shall be equipped with a siren, whistle or bell, capable of emitting sound audible under normal conditions from a distance of not less than five hundred (500) feet and of a type approved by the superintendent, but the siren shall not be used except when the vehicle is operated in response to an emergency call or in the immediate pursuit of an actual or suspected violator of the law, in which case the driver of the vehicle shall sound the siren when reasonably necessary to warn pedestrians and other drivers of the approach thereof.

(e) This section applies to motorcycles, motor-driven cycles, multipurpose vehicles and mopeds.

31-5-953. Mufflers.

(a) Every vehicle shall be equipped, maintained and operated so as to prevent excessive or unusual noise. Every motor vehicle shall at all times be equipped with a muffler or other effective noise suppressing system in good working order and in constant operation. No person shall use a muffler cut-out, bypass or similar device.

(b) The engine and power mechanism of every motor vehicle shall be so equipped and adjusted as to prevent the escape of excessive fumes or smoke.

31-5-954. Mirrors.

(a) On or before January 1, 1986, every motor vehicle including motorcycles, motor-driven cycles, multipurpose vehicles and mopeds shall be equipped with a mirror mounted on the left side of the vehicle and so located as to reflect to the driver a view of the highway to the rear of the vehicle.

(b) Every motor vehicle except a motorcycle, motor-driven cycle or moped, shall be equipped with an additional mirror mounted either inside the vehicle approximately in the center or outside the vehicle on the right side and so located as to reflect to the driver a view of the highway to the rear of the vehicle.

31-5-955. Windshields and wipers.

(a) No person shall drive any motor vehicle with any sign, poster or other material or substance upon or crack within the front windshield, side or rear windows of the vehicle which materially obstructs, obscures or impairs the driver's clear view of the highway or any intersecting highway.

(b) The windshield on every motor vehicle shall be equipped with a device for cleaning rain, snow or other moisture from the windshield, which device shall be so constructed as to be controlled or operated by the driver of the vehicle. This subsection shall apply to multipurpose vehicles as defined in W.S. 31-1-101(a)(xv)(M) when equipped with a windshield and an enclosed cab.

(c) Every motor vehicle shall be equipped with a windshield and a windshield wiper which shall be maintained in good working order.

31-5-956. Tires; restriction of travel under hazardous conditions; penalties.

(a) Every solid rubber tire on a vehicle shall have rubber on its entire traction surface at least one (1) inch thick above the edge of the flange of the entire periphery.

(b) No person shall operate or move on any highway any motor vehicle, trailer or semitrailer having any metal tire in contact with the roadway.

(c) No tire on a vehicle moved on a highway shall have on its periphery any protuberance of any material other than rubber which projects beyond the tread of the traction surface of the tire, except that it shall be permissible to use:

(i) Implements of husbandry with tires having protuberances which will not injure the highway;

(ii) Tire chains of reasonable proportions upon any vehicle when required for safety because of snow, ice or other conditions tending to cause a vehicle to skid;

(iii) Pneumatic tires having studs designed to improve traction without materially injuring the surface of the highway. Pneumatic tires having studs must be approved by the superintendent.

(d) The superintendent and local authorities in their respective jurisdictions may issue special permits authorizing the operation upon a highway of tractors having movable tracks with transverse corrugations upon the periphery of the movable tracks or farm tractors or other farm machinery, the operation of which upon a highway would otherwise be prohibited under this section.

(e) When the superintendent or his authorized representative determines that travel is sufficiently hazardous due to snow, ice or other conditions travel on a highway may be restricted to use only by motor vehicles utilizing adequate snow tires or tire chains, motor vehicles that are all-wheel drive vehicles or necessary emergency vehicles as defined in W.S. 31-5-102(a)(ii), including snow plows. The superintendent or his authorized representative may further restrict travel in extremely hazardous conditions to use only by necessary emergency vehicles as defined in W.S. 31-5-102(a)(ii), including snow plows, and those vehicles utilizing tire chains or to all-wheel drive vehicles utilizing adequate snow tires with a mud and snow or all-weather rating from the manufacturer having a tread of sufficient abrasive or skid-resistant design or composition and depth to provide adequate traction under existing driving conditions. The prohibition or restriction of use shall be effective when signs, including temporary or electronic signs, giving notice thereof are erected upon that portion of the highway, and it shall be unlawful to proceed in violation of the notice. The operator of a commercial vehicle shall affix tire chains to at least two (2) of the drive wheels of the vehicle at opposite ends of the same drive axle when the vehicle is required to utilize tire chains under this subsection. The state highway patrol shall cooperate with the department in the enforcement of any closing or restriction of use under this subsection.

(f) A person shall not operate any vehicle when one (1) or more of the tires in use on that vehicle is in unsafe operating condition or has a tread depth less than four thirty-seconds (4/32) inch in the case of tires which are used on the front wheels of a bus, truck or truck tractor, or two thirty-seconds (2/32) inch in other cases, measured in any two (2) adjacent tread grooves at three (3) equally spaced intervals around the circumference of the tire but the measurements shall not be made at the location of any tread wear indicator, tie bar, hump or fillet. No vehicle shall be operated on any tire that has fabric exposed through the tread or sidewall.

(g) A person in the business of selling tires shall not sell or offer for sale for highway use any tire which is in unsafe condition or which has a tread depth of less than two thirty-seconds (2/32) inch measured as specified in subsection (f) of this section.

(h) This section applies to motorcycles, motor-driven cycles, multipurpose vehicles and mopeds.

(j) Any person who operates a motor vehicle in violation of restrictions imposed by the department or the highway patrol under subsection (e) of this section is guilty of a misdemeanor and upon conviction shall be subject to a penalty of not more than two hundred fifty dollars ($250.00). Any person who operates a motor vehicle in violation of restrictions imposed by the department or the highway patrol under subsection (e) of this section, where the result of the violation is an incident that causes the closure of all lanes in one (1) or both directions of the highway, is guilty of a misdemeanor and upon conviction shall be subject to a penalty of not more than seven hundred fifty dollars ($750.00).

(k) As used in this section, "tire chains" means metal chains which consist of two (2) circular metal loops, one (1) on each side of the tire, connected by not less than nine (9) evenly spaced chains across the tire tread and any other traction devices differing from metal chains in construction, material or design but capable of providing traction equal to or exceeding that of metal chains under similar conditions.

31-5-957. Required flares, lanterns or reflectors for certain vehicles.

(a) No person shall operate any truck more than eighty (80) inches in width, bus, truck-tractor or any motor vehicle towing a house trailer, upon any highway outside an urban district or upon any divided highway unless there is carried in the vehicle the following equipment except as provided in subsection (b) of this section:

(i) At least three (3) flares or three (3) red electric lanterns or three (3) portable red emergency reflectors, each of which shall meet the requirements in SAE Standards J596 and J597 and Federal Motor Vehicle Safety Standard No. 125. No flare, fusee, electric lantern or warning flag shall be used for the purpose of compliance with the requirements of this section unless the equipment is of a type which has been submitted to the superintendent and approved by him. No portable reflector unit shall be used for the purpose of compliance with the requirements of this section unless it is so designed and constructed as to be capable of reflecting red light clearly visible from all distances within six hundred (600) feet to one hundred (100) feet under normal atmospheric conditions at night when directly in front of lawful lower beams of head lamps and unless it is of a type which has been submitted to the superintendent and approved by him;

(ii) At least three (3) red-burning fusees unless red electric lanterns or red portable emergency reflectors are carried.

(b) No person shall use or permit the use of any flame-producing emergency signal for protecting any vehicle transporting explosives, Class A or Class B, any cargo tank motor vehicle used for the transportation of any flammable liquid or flammable compressed gas, whether loaded or empty, or any motor vehicle using compressed gas as motor fuel. In lieu thereof, emergency reflective triangles, red electric lanterns or red emergency reflectors shall be used, the placement of which shall be in the same manner as prescribed in W.S. 31-5-958.

31-5-958. Display of warning devices when vehicle disabled.

(a) Whenever any truck, bus, truck tractor, trailer, semitrailer or pole trailer eighty (80) inches or more in overall width or thirty (30) feet in overall length is stopped upon a roadway or adjacent shoulder, the driver shall immediately actuate vehicular hazard warning signal lights meeting the requirements of W.S. 31-5-923 when warning signal lights are required by W.S. 31-5-923. The lights need not be displayed by a vehicle parked lawfully in an urban district, or stopped lawfully to receive or discharge passengers, or stopped to avoid conflict with other traffic or to comply with the directions of a police officer or an official traffic-control device or while the devices specified in subsections (b) through (g) of this section are in place.

(b) Whenever any vehicle of a type referred to in subsection (a) of this section is disabled, or stopped for more than ten (10) minutes, upon a roadway outside of an urban district at any time when lighted lamps are required, the driver of the vehicle shall display the following warning devices except as provided in subsection (c) of this section:

(i) A lighted fusee, a lighted red electric lantern or a portable red emergency reflector shall be immediately placed at the traffic side of the vehicle in the direction of the nearest approaching traffic;

(ii) As soon thereafter as possible but in any event within the burning period of the fusee (ten (10) minutes), the driver shall place three (3) liquid-burning flares (pot torches), three (3) lighted red electric lanterns or three (3) portable red emergency reflectors on the roadway in the following order:

(A) One (1) approximately one hundred (100) feet from the disabled vehicle in the center of the lane occupied by the vehicle and toward traffic approaching in that lane;

(B) One (1) approximately one hundred (100) feet in the opposite direction from the disabled vehicle and in the center of the traffic lane occupied by the vehicle;

(C) One (1) at the traffic side of the disabled vehicle not less than ten (10) feet rearward or forward thereof in the direction of the nearest approaching traffic. If a lighted red electric lantern or a red portable emergency reflector has been placed at the traffic side of the vehicle in accordance with paragraph (b)(i) of this section, it may be used for this purpose.

(c) Whenever any vehicle referred to in this section is disabled, or stopped for more than ten (10) minutes, within five hundred (500) feet of a curve, hillcrest or other obstruction to view, the warning device in that direction shall be so placed as to afford ample warning to other users of the highway, but in no case less than one hundred (100) feet nor more than five hundred (500) feet from the disabled vehicle.

(d) Whenever any vehicle of a type referred to in this section is disabled, or stopped for more than ten (10) minutes, upon any roadway of a divided highway during the time that lighted lamps are required, the appropriate warning devices prescribed in subsections (b) and (e) of this section shall be placed as follows:

(i) One (1) at a distance of approximately two hundred (200) feet from the vehicle in the center of the lane occupied by the stopped vehicle and in the direction of traffic approaching in that lane;

(ii) One (1) at a distance of approximately one hundred (100) feet from the vehicle, in the center of the lane occupied by the vehicle and in the direction of traffic approaching in that lane;

(iii) One (1) at the traffic side of the vehicle and approximately ten (10) feet from the vehicle in the direction of the nearest approaching traffic.

(e) Whenever any motor vehicle used in the transportation of explosives or any cargo tank truck used for the transportation of any flammable liquid or compressed flammable gas is disabled, or is stopped for more than ten (10) minutes, at any time or place mentioned in subsection (b), (c) or (d) of this section, the driver of the vehicle shall immediately display red electric lanterns or portable red emergency reflectors in the same number and manner specified therein. Flares, fusees or signals produced by flame shall not be used as warning devices for disabled vehicles of the type mentioned in this subsection nor for vehicles using compressed gas as a fuel.

(f) The flares, fusees, red electric lanterns and portable red emergency reflectors to be displayed as required in this section shall conform with the requirements of W.S. 31-5-957 applicable thereto.

(g) The warning devices described in subsections (b), (c), (d) and (e) of this section need not be displayed where there is sufficient light to reveal persons and vehicles within a distance of one thousand (1,000) feet.

(h) When any vehicle described in this section is stopped entirely off the roadway and on an adjacent shoulder at any time and place described, the warning devices shall be placed, as nearly as practicable, on the shoulder near the edge of the roadway.

31-5-959. Vehicles transporting hazardous materials.

(a) Any person operating any vehicle transporting any hazardous materials, hazardous substance, hazardous waste, marine pollutant or radioactive material as a cargo or part of a cargo upon a highway shall at all times comply with regulations of the department adopted pursuant to W.S. 31-18-303. The regulations shall be consistent with current hazardous materials regulations of the United States department of transportation.

(b) No person shall dispose of or deposit any hazardous materials, hazardous substance, hazardous waste, marine pollutant or radioactive material upon any public street, road or highway in the state. However, the department of environmental quality or department of transportation may grant approval for the disposal or deposit of any material according to law.

(c) Any person convicted of willfully violating subsection (b) of this section is guilty of a felony punishable by a fine of not more than ten thousand dollars ($10,000.00), imprisonment for not more than five (5) years, or both. Any person convicted of recklessly, as defined by W.S. 6-1-104(a)(ix), violating subsection (b) of this section is guilty of a felony punishable by a fine of not more than five thousand dollars ($5,000.00), imprisonment for not more than three (3) years, or both. Any person convicted of criminal negligence, as defined by W.S. 6-1-104(a)(iii), in violating subsection (b) of this section is guilty of a misdemeanor punishable by a fine of not more than one thousand dollars ($1,000.00), imprisonment for not more than one (1) year, or both.

(d) As used in this section:

(i) "Hazardous materials" means a substance or material, including a hazardous substance, which has been determined by the United States secretary of transportation under title 49 of the Code of Federal Regulations to be capable of posing an unreasonable risk to health, safety and property and which has been so designated;

(ii) "Hazardous waste" means any material that is subject to the hazardous waste manifest requirements of the United States environmental protection agency as specified in 40 C.F.R. part 262;

(iii) "Marine pollutant" means a hazardous substance which is listed in appendix b, 49 C.F.R. part 172.101 and, when in a solution or mixture of one (1) or more marine pollutants, is packaged in a concentration which equals or exceeds:

(A) Ten percent (10%) by weight of the solution or mixture for materials that are listed in the appendix;

(B) One percent (1%) by weight of the solution or mixture for materials that are identified as severe marine pollutants in the appendix.

(iv) "Radioactive material" means any material having a specific activity greater than 0.002 microcuries per gram;

(v) "Specific activity" of a radionuclide means the activity of the radionuclide per unit mass of that nuclide. The specific activity of a material in which the radionuclide is essentially uniformly distributed is the activity per unit mass of the material.

31-5-960. Pedestrian vehicles.

(a) Every pedestrian vehicle operated upon a highway shall be equipped with the following equipment:

(i) A horn meeting the requirements of W.S. 31-5-952(a);

(ii) At least one (1) headlamp of either a single-beam or multiple-beam type which shall be of sufficient intensity to reveal a person or a vehicle at a distance of not less than one hundred (100) feet when operated at any speed less than twenty-five (25) miles per hour;

(iii) Two (2) tail lamps which shall be so wired as to be lighted whenever the headlamp is lighted and which, when lighted, shall emit a red light plainly visible from a distance of at least one hundred (100) feet to the rear;

(iv) Rear stop lamps and turn signals conforming to the requirements of the superintendent;

(v) A brake which conforms to the performance requirements of W.S. 31-5-951; and

(vi) A reflectorized flag mounted in a bracket permanently affixed to the vehicle. The flag, when mounted, shall be visible from all directions at a height of not less than forty-eight (48) inches nor more than seventy-two (72) inches measured from the level ground upon which the vehicle stands and shall conform to the following requirements:

(A) Be constructed of durable, all-weather type material;

(B) Be orange in color;

(C) Be triangular in shape with a minimum base length of eight and one-half (8 1/2) inches and a minimum side length of eleven and one-half (11 1/2) inches.

31-5-961. Television receivers; electronic displays.

(a) No motor vehicle operated on Wyoming highways shall be equipped with television-type receiving equipment so located that the viewer or screen is visible from the driver's seat.

(b) This section does not prohibit the use of television-type receiving equipment used exclusively for safety or law enforcement purposes, provided the use is approved by the highway department.

31-5-962. Sunscreening devices.

(a) As used in this section:

(i) "Dealer" means any person or business engaged in the distribution or installation of sunscreening products or materials designed to be used in conjunction with vehicle glazing materials for the purpose of reducing the effects of the sun;

(ii) "Light transmission" means the ratio of the amount of total light to pass through a product or material to the amount of the total light falling on the product or material;

(iii) "Luminous reflectance" means the ratio of the amount of total light that is reflected outward by the product or material to the amount of the total light falling on the product or materials;

(iv) "Multipurpose passenger vehicle" means a motor vehicle designed to carry ten (10) persons or less which is constructed either on a truck chassis or with special features for occasional off-road operation;

(v) "Nonreflective" means a product or material designed to absorb light rather than to reflect it;

(vi) "Sunscreening device" means film material or device that is designed to be used in conjunction with motor vehicle safety glazing materials for reducing the effects of the sun.

(b) No person may operate an enclosed motor vehicle that is registered or required to be registered in this state on any public highway, road or street that has a sunscreen device on the windshield, the front side wings and side windows adjacent to the right and left of the driver and windows adjacent to the rear of the driver that do not meet the requirements of this section.

(c) A sunscreening device when used in conjunction with the windshield shall be a nonreflective type and may not be red, yellow or amber in color. A sunscreening device may be used only along the top of the windshield and may not extend downward beyond the AS-1 line or more than five (5) inches from the top of the windshield, whichever is closer to the top of the windshield.

(d) A sunscreening device, when used in conjunction with the safety glazing materials of the side wings or side windows, or both, located at the immediate right and left of the driver, shall be a nonreflective type and have total light transmission through both the sunscreening device and glazing of not less than twenty-eight percent (28%).

(e) A sunscreening device, when used in conjunction with the safety glazing materials of the side windows behind the driver and the rearmost window, shall be a nonreflective type and have total light transmission through both the sunscreening device and glazing of not less than twenty-eight percent (28%).

(f) No sunscreening device or tinting film may be applied or affixed to any window of a motor vehicle that has a luminous reflectance of light exceeding twenty percent (20%).

(g) If any sunscreen device or tinting film is added to any windows behind the operator, one (1) left and one (1) right outside rearview mirror shall be required.

(h) The requirements of this section shall not apply to windows behind the driver of trucks, buses, motor homes, ambulances, limousines and multipurpose passenger vehicles, to windshields on motorcycles or motor-driven cycles. Except as provided in subsection (j) of this section, vehicle windows with a sunscreen device or tinting film applied prior to July 1, 1996 which do not meet the specifications established by this section shall be in violation after December 31, 1996.

(j) Notwithstanding the requirements of subsections (d) and (e) of this section, any sunscreening device applied prior to July 1, 1996, when used in conjunction with the safety glazing materials of the side wings or side windows located at the immediate right and left of the driver, the side windows behind the driver and the rearmost window shall be of a nonreflective type and have total light transmission through both the sunscreening device and the glazing of not less than thirteen percent (13%).

(k) No person or firm may apply or affix to the windows of any motor vehicle in this state, a sunscreen device or tinting film that is not in compliance with the requirements of this section.

(m) Notwithstanding the requirements of this section, a motor vehicle operated by or regularly used to transport any person with a medical condition which renders him susceptible to harm or injury from exposure to sunlight or bright artificial light may be equipped, on its windshield and any or all of its windows, with sun shading or tinting films or applications which reduce the transmission of light into the vehicle to levels not less than twenty-five percent (25%). The sun shading or tinting film when applied to the windshield of a motor vehicle shall not cause the total light transmittance to be reduced to any level less than seventy percent (70%), except for the upper five (5) inches of the windshield or the AS-1 line, whichever is closer to the top of the windshield. Vehicles equipped with sun shading or tinting films as provided in this subsection shall not be operated on any highway unless the driver or an occupant of the vehicle has in his possession a certificate issued by the director authorizing such operation. The director shall issue the certificate only upon receipt of a signed statement from a licensed physician or licensed optometrist identifying the person seeking the certificate and stating that, in the physician's or optometrist's professional opinion, the equipping of a vehicle with sun shading or tinting films or applications is necessary to safeguard the health of the person seeking the certificate. Certificates issued by the director under this subsection shall be valid so long as the condition requiring the use of sun shading or tinting films or applications persists or until the vehicle is sold, whichever first occurs. In the discretion of the director, one (1) or more certificates may be issued to an individual or a family.

(n) This section shall apply to multipurpose vehicles as defined in W.S. 31-1-101(a)(xv)(M) when equipped with a windshield and an enclosed cab.

31-5-970. Required safe mechanical condition.

No person shall drive or move on the highway any vehicle, including vehicles referenced in W.S. 31-5-901(c), unless the equipment upon the vehicle is in good working order and adjustment as required in this act and unless the vehicle is in such safe mechanical condition as not to endanger the driver or other occupant or any person upon the highway.