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Are there safety regulations limiting the brightness of headlights? About one in 20 vehicles appears to be driving with its brights on, but I suspect some are mis-pointed, or have aftermarket bulbs. It's uncomfortable and dangerous to meet these vehicles oncoming at night. – Mark

There are indeed regulations regarding this issue. They are covered under Canada Motor Vehicle Safety Standard (CMVSS) 108 (Lighting Systems and Retroreflective Devices). These regulations require that headlamps provide illumination necessary for safe night driving while eliminating or limiting glare.

Transport Canada says "the requirements set the minimum and maximum allowable height for the installation of headlamps, the maximum and minimum light intensities of headlamps, as well as the requirement for a tell-tale to alert the driver when the upper beam headlamps are switched on."

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The regulations are based on two criteria: 1) To illuminate the roadway far enough ahead of the vehicle so that the driver has time to react and stop the vehicle before striking an object in the vehicle's path and 2) To avoid excessive glare to other drivers, Transport Canada says.

It also says "the basic headlamp beam pattern performance requirements of all international regulations are virtually identical, with the only difference being the initial aim of headlamps, which is dictated by the diverse road infrastructure found in different countries."

Headlamp manufacturers work closely with vehicle manufacturers to ensure the units work as required when installed in specific models. To give a specific example, the latest version of CMVSS 108, revision 5, with a mandatory compliance date of January, 2012, states that in the case of one sealed beam unit on each side of the vehicle with two filaments, they have a maximum of 43-watts on high beam and 65-watts on low beam. Where the vehicle has two sealed beam headlights on each side, the limits are 65-70 watts for high beam and 55-60 watts on low, depending on design and associated hardware.

For the increasingly more common headlights with replaceable bulbs, specifications regarding "brightness" have to do with the bulb itself as well as the reflector. The standards dictate the manufacture and testing of approved bulbs, markings they must display indicating compliance and their composition. These specifications contain standards issued by the Society of Automotive Engineers, ECE (European regulations) or the International Electrotechnical Commission (IEC).

Replacement seats

In your article discussing replacement seats for a late-model Ford pickup, you mention contacting a specialty seat manufacturer. Another issue the reader might want to consider is that, with respect to airbags integrated into the seats, that may be compromised with the addition of aftermarket seat covers. – Douglas

Good point. Not only might the airbags be rendered ineffective or less effective, they might actually be more dangerous when deployment is hampered or redirected by a after-market seat cover. The bags are carefully designed using computer simulation and real world crash tests. The speed of deployment, direction of deployment and ability to deflate quickly are all issues that come into play.

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