Why haven't they gone to a graduated brake light system? With today's access to technology, it must a simple process to design a brake light switch that connects to the brake fluid plumbing. When a driver steps on the brake, the brake light intensity would correspond to the pressure being applied to the brake pedal. Where this comes into play is those situations, especially at night, when we are stuck following a nervous Nelly on that twisty secondary road who's driving with one foot on the gas and one foot resting on the brake. I find it hard to believe that no manufacturer has considered this system yet so it must be government regulations. – Lou
Brake lights that rev up and down like the LED equalizer on an '80s ghetto blaster are forbidden by U.S. and Canadian regulations – brake lights can't flash or vary in intensity, Transport Canada says.
"Graduated brake lights, such as those that get brighter or that light up gradually in sections, are not allowed according to Canadian, U.S. or United Nations' regulations," says Transport Canada spokesperson Maryse Durette. "Additional (brake) lights are, however, allowed in Canada if they do not interfere with what is required by regulation."
Transport Canada says UN regulations do allow brake lights to flash in case of high deceleration braking – and they're permitted to flash faster than turn signals or hazard lights. Durrette says Transport Canada "might consider" allowing this in future amendments to lighting regulations.
There are no plans to change the law, but Transport Canada is working with the U.S. to update lighting rules, Durette says.
At least one U.S. study recommends brake lights that flash and get brighter – but only during a sudden stop – as a way to reduce rear end crashes caused by inattentive drivers.
At least 29 per cent of accidents in the United States are rear-end collisions, and the majority of those are cars hitting a stopped car, usually during the day when visibility is at its best, says the 2009 study by the National Highway Traffic Safety (NHTS) administration.
The most common cause? Drivers not paying attention.
Over the years, various systems have been suggested, but there's a worry that too complicated a light system might just confuse or distract drivers.
The drivers in the NHTS study generally understood – and responded to – lights that got brighter and flashed quickly in an emergency stop.
The study suggested that lights should activate based on signals from an accelerometer and from the vehicle's anti-lock brake system.
Mercedes was given special permission to test its adaptive brake lights (which is available on some Mercedes vehicles in Europe) on U.S. roads for two years starting in 2006.
Mercedes says studies show emergency flashing brake lights improve drivers' brake-activation response times by up to 0.2 seconds. If a car's going 80 km/h, that would mean the stopping distance could be reduced by more than 4 metres, Mercedes says.
Right now, several auto makers offer what they call adaptive brake lights – but these don't flash or vary in brightness. BMW's system, for example, uses a second, brighter brake light that lights up during sudden stops. That's allowed by Canadian rules.
And, except with daytime running lights, Canada follows the vehicle rules set by the United States, says the Canadian Vehicle Manufacturers' Association (CVMA).
"Any regulatory changes to allow new brake lighting systems would need to be co-ordinated between both countries to minimize issues for drivers travelling between countries and to continue to allow for the importation of used vehicles from one country to the other," says CVMA president Mark Nantais.
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