One of the more frequent vehicle equipment complaints that I receive is about headlight glare. I am told that they are horrendous to an oncoming driver and it is hazardous to be driving because they are blinding. Drivers want to take their eyes off the road or look to the side to avoid them. Are they legal?
The situation may be from one of three causes: poor design, a standard high intensity discharge (HID) headlamp or an improper retrofit.
To encourage vehicle manufacturers to improve their headlight designs, the Insurance Institute for Highway Safety (IIHS) has begun to rate vehicles for headlight performance. According to them, headlights are still an afterthought on most vehicles in 2020, with only six of the 156 models having good-rated headlights across the board.
Tungsten filament sealed beam headlamps originated in 1940. They were improved by the introduction of the halogen sealed beam in 1962 and the replaceable halogen bulb in 1983. This change allowed for greater high beam intensity.
The next significant improvement was the HID headlamp that used a glass capsule of glowing gas to produce light instead of a heated tungsten filament. The system can be two to three times more efficient at producing light than the tungsten bulb. They produce more light in the blue end of the spectrum compared to the filament bulb which tends more toward the red.
It appears that it may be the blue tendency that bothers drivers (especially older drivers) looking into these lights. Research is finding that the HID lamp does produce more discomfort glare but the reason is not currently clearly understood.
The current innovation in vehicle headlighting is the LED sealed beam.
Discounting the installation of lights that are either not meant for automotive use, eg: aircraft landing lights and non-standard LED lighting purchased online, we have improper replacements widely available at local merchants. The words “for off road use only” or “check with local authorities before use” are often buried, unnoticed, in the packaging.
Over wattage tungsten filament bulbs were the first end user modification to create excessive glare. Any tungsten filament headlight bulb rated at more than 65W is illegal to use on our highways.
LED and HID capsules made to fit standard headlamp housings are available for purchase. These are illegal for use in British Columbia because they produce even more glare than proper HID lamp systems.
In the HID systems you have a capsule, reflector and lens all designed to work together. Capsules inserted into standard housings and reflectors do not distribute the light properly. This definitely affects oncoming drivers and could prevent proper vision for the driver of the vehicle fitted with them.
The LEDs in sealed units are not removable and the entire assembly must be replaced when they fail.