§ 345.34 SUN SCREENING DEVICES.
   (a)   No person may operate a motor vehicle that is registered or required to be registered in the state on any public highway, road, or street that has a sun screening 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; provided, that law enforcement K-9 and other emergency vehicles that are designed to haul animals, unmarked law enforcement vehicles primarily used for covert or undercover enforcement, and automobiles that have sun-screening devices installed at the factory by the manufacturer are exempt from this requirement. No unmarked law enforcement vehicle, herein exempted, may engage in routine traffic stops.
   (b)   A sun screening device when used in conjunction with the windshield must be nonreflective and may not be red, yellow, or amber in color. A sun screening device may be used only along the top of the windshield and may not extend downward beyond the ASI line or more than five inches from the top of the windshield, whichever is closer to the top of the windshield.
   (c)   A sun screening device when used in conjunction with the automotive safety glazing materials of the side wings or side windows located at the immediate right and left of the driver shall be a nonreflective type with reflectivity of not more than 20% and have a light transmission of not less than 35%. The side windows behind the driver and the rear most windows may have a sun screening device that is designed to be used on automotive safety glazing materials that has a light transmission of not less than 35% and a reflectivity of not more than 20%. If a sun screening device is used on glazing behind the driver, one right and one left outside rear view mirror is required.
   (d)   Each manufacturer shall:
      (1)   Certify to the State Police and Division of Motor Vehicles that a sun screening device used by it is in compliance with the reflectivity and transmittance requirements of this section;
      (2)   Provide a label not to exceed one and one-half square inches in size, with a means for the permanent and legible installations between the sun screening material and each glazing surface to which it is applied that contains the manufacturer’s name and its percentage of light transmission; and
      (3)   Include instructions with the product or material for proper installation, including the affixing of the label specified in this section. The labeling or marking must be placed in the left lower corner of each glazing surface when facing the vehicle from the outside.
   (e)   No person shall:
      (1)   Offer for sale or for use any sun screening product or material for motor vehicle use not in compliance with this section; or
      (2)   Install any sun screening product or material on vehicles intended for use on public roads without permanently affixing the label specified in this section.
   (f)   The provisions of this section do not apply to a motor vehicle registered in this state in the name of a person, or the person’s legal guardian, who has an affidavit signed by a physician or an optometrist licensed to practice in this state that states that the person has a physical condition that makes it necessary to equip the motor vehicle with sun screening material which would be of a light transmittance or luminous reflectance in violation of this section. The affidavit must be in the possession of the person so afflicted, or the person’s legal guardian, at all times while being transported in the motor vehicle.
   (g)   The light transmittance requirement of this section does not apply to windows behind the driver on trucks, buses, trailers, mobile homes, and multi-purpose passenger vehicles.
   (h)   As used in this section:
      BUS. A motor vehicle with motive power, except a trailer, designed for carrying more than ten persons.
      LIGHT TRANSMISSION. 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.
      LUMINOUS REFLECTANTS. 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.
      MANUFACTURER. Any person engaged in the manufacturing or assembling of sun screening products or materials designed to be used in conjunction with vehicle glazing materials for the purpose of reducing the effects of the sun.
      MOTOR HOMES. Vehicular units designed to provide temporary living quarters built into and an integral part of or permanently attached to a self-propelled motor vehicle chassis.
      MULTI-PURPOSE PASSENGER VEHICLE. A motor vehicle with motive power, except a trailer, designed to carry ten persons or less which is constructed either on a truck chassis or with special features for occasional off-road operation.
      NONREFLECTIVE. A product or material designed to absorb light rather than to reflect it.
      PASSENGER CAR. A motor vehicle with motive power, except a multi-purpose passenger vehicle, motorcycle, or trailer, designed for carrying ten persons or less.
      SUN SCREENING DEVICE. 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.
      TRUCK. A motor vehicle with motive power, except a trailer, designed primarily for the transportation of property or special purpose equipment.
(W. Va. Code 17C-15-36a)