IN REGARDS TO THE TINTING OF FRONT WINDOWS
Regulations specify that the nearside and offside front windows, for which the driver uses for forward vision and when using external rear facing mirrors, must permit a light transmittance value of at last 70%(for motor vehicles first used on or after 1st April 1985), with the front windscreen permitting a light transmittance value of 75%.
Under the Rod vehicles (Construction and Use) Regulations 1986 (Section 32) and the Road Traffic Act 1988 (Section 76, it is an offence to (a) fit a vehicle part to a vehicle, or (b) cause or permit a vehicle part to be fitted to a vehicle in such circumstances that the use of the vehicle on a road would, by reason of that part being fitted to the vehicle involve a danger of injury to any person or, constitute a contravention of or failure to comply with any of the construction and use requirements.
Fore more information please follows the links below
http://www.gov.uk/tinted-vehicle-window-rules
http://www.legislation.gov.uk/ukpga/1988/52/section/76
http:www.legislation.gov.uk/uksi/1986/1078/introduction/made
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