IWFA Position on MPVs

In an effort to clarify the requirements and restrictions placed on the application of window film to the windows of Multipurpose Passenger Vehicles (as defined at 49 CFR 571.3) as prescribed by the United States Government, the International Window Film Association (IWFA) ascribes the following interpretation to codes, regulations and safety standards applicable to the above topic.  IWFA believes these laws apply only to the safety glazing material and for no reason should it be construed to include after-market window film, or restrict each individual state’s rights to regulate the application of window film in accordance with the customs and laws of that state.

The United States Secretary of Transportation, under 49 U.S.C. 30111, is authorized to develop safety standards for motor vehicles.  Window glazing materials are regulated within standard 205 of the “Federal Motor Vehicle Safety Standards” (49 CFR 571.205 hereinafter “FMVSS 205”).  FMVSS 205 states that a Multipurpose Passenger Vehicle (MPV), as defined at 49 CFR 571.3, be treated the same as a truck, and requires that window glazing material in motor vehicles conform to American National Standard ``Safety Code for Safety Glazing Materials for Glazing Motor Vehicles Operating on Land Highways'' (ANS Z26.1-1977 hereinafter “the safety code”). 

The safety code delineates several different levels of approved glass for use in specific places on specific types of vehicles, which must pass certain combinations of durability tests (Items 1-13 ANS Z26.1-1990 at 9-13, hereinafter AS-1 through AS-13).  These tests are designed to test strength, durability and visibility of the materials that are used to glaze glass for use in motor vehicles in order to reduce the risk of injury in a crash.  Several types of safety glazing materials are considered suitable for the same positions in vehicles and for the purpose of this paper, the lowest requirements for any particular position in a vehicle will be the requirement referred to as the standard.

The windshields of every motor vehicles is required to be constructed of AS-1 glass, which is subject to Test 2 in section 5 of the safety code.  Test 2 requires the safety glazing material to maintain a light transmittance of no less than 70%.  Either AS-1 or AS-2 (which must also pass Test 2) glass may be used in the passenger and rear windows of passenger vehicles and the windows to the immediate right and left of the driver in MPVs. 

For all windows behind the B pillar of an MPV, it is permissible to install safety glazing material with the classifications of AS-1, AS-2, AS-3, AS-4, AS-5, AS-6, AS-8 and AS-9.  It is not necessary for safety glazing material to pass Test 2 to obtain the AS-3, AS-5 or AS-9 classifications.  As a result, safety glazing material with a light transmittance of less than 70% may be installed behind the B pillar of MPVs.  Again, the safety code does not restrict the further darkening of these windows by the application of after-market window film products.

To obtain the AS-3 or AS-9 classification, the safety glazing material must meet the standards set forth in Test 1.  Test 1 is designed to determine the effect of sunlight on the safety glazing material.  The safety glazing material, after simulated exposure to sunlight, must retain at least 70% of the original light transmittance of the specimen to be in compliance with the standards set forth in Test 1.  Simply stated, if the specimen originally had a light transmittance of 35%, then, after administering the test, it must have a light transmittance of at least 24.5%.  Automotive manufacturers most commonly install AS-3 glass in the rear windows of MPVs with visible light transmissions ranging from completely transparent to as low as 15%. 

Recently, a new class of vehicles has emerged on the market commonly referred to as “Crossover Vehicles.”  These vehicles often represent the hybrid of an SUV and a station wagon or mini-van.  There has been some debate concerning the application of the definition of MPV to these vehicles.  IWFA takes the position that the definition of MPV should be strictly applied to all vehicles.  As an organization, IWFA promotes the legal tinting of vehicles and believes that the law should be followed to the letter.  Therefore, those vehicles, which are not built on truck frames or intended for occasional off-road use, are not covered under the safety code exemption.