European directive 76/756/EC which came into force on the 1st October 1977 governs the "E-marking" of vehicle lights for any of "our" cars that were first used/registered on or after this date.

Therefore any vehicle first used/registered on/after 1st October 1977 MUST use "E" marked lighting components when used ON THE ROAD. If the vehicle is not using "E" marked components (including bulbs) then it is illegal and in contravention of the various Road Traffic Acts and Vehicle Lighting regulations.

High wattage head light bulbs ARE NOT "E" marked, and are therefore illegal to use on cars first used/registered ON or AFTER 1st October 1977.

For vehicles first used/registered PRIOR to 1st Oct 1977, NO SUCH REGULATION EXISTS - it's just a case of "you must not dazzle on coming traffic"