Vehicle Headlights

LED vehicle headlights are incompatible with dark-adapted human eyesight, they are too bright, too blue and too ‘concentrated’. It is not only light sensitive people who are saying this, an RAC Survey, published in March 2022, found 89 per cent of drivers think that some or most vehicle headlights are too bright.

The human eye has evolved to allow it to adapt to a wide range of light levels from bright sunlight to almost total darkness. But it cannot adapt in a short space of time. Comfortable vision requires a limited range of light levels at any particular time and excessive changes and contrasts in light levels in a brief period cause disabling glare. The problem with LED headlights is that they are incompatible with dark-adapted human eyesight – particularly for older drivers – they are too bright, too blue, too ‘concentrated’ and blinding over too long a distance.

The explanation given by some people in the car industry is that these problem headlights are badly adjusted, so they are not properly directed at the road, and that simply correcting this would end the issue. This might be reasonable if we all drove on straight flat roads all the time and headlights were all the same height. Unfortunately, this is not the case – British roads have bends, bumps, hills and dales which turn LED headlights into a blinding danger for drivers. RAC surveys consistently find that most drivers are unhappy with new vehicle headlights and many older drivers have given up driving at night..

LightAware calls on the UK Government to:

• Direct the National Institute for Health Protection to sponsor research to establish how vehicle lighting cause discomfort in drivers, other susceptible individuals, cyclists and pedestrians.
• Use this research to set standards for brightness, flicker and colour temperature of vehicle headlights, including a ban on exceeding a brightness threshold to ensure that people can drive safely and reduce the discomfort of others.
• Set legal limits for the amount of blue light that vehicle headlights can have in their spectrum by setting standards for their colour temperature.

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