A new report entitled Modern vehicle headlights dazzle drivers and may compromise road safety, put together by concerned road users, light experts and other specialists, says vehicle headlights should be regulated to reduce the dazzle they cause on-coming drivers.
Fronted by Baroness Hayter, a long-term consumer champion, and including the LightAware charity, the report urges governments to undertake research to better understand causes of the problem, and to investigate the need to introduce appropriate standards on high-tech, high-spec LED headlights.
Menace of headlight dazzle
In its foreword Hayter writes: “It’s not your eyes; it’s the on-coming headlights. Optometrists are seeing an increasing number of patients no longer driving at night because of headlight dazzle, which, in winter months, means short days leave very little driving time.
“Put simply, new technology’s innovative headlights, which might illuminate the road for the person behind the wheel, are a menace for on-coming vehicles or pedestrians,” she says.
“It’s worse in built-up areas, with ‘sleeping policemen’ causing an oncoming car suddenly to angle upwards, but also in country lanes where a car appears round a bend before its supposedly clever computer has dipped or angled the headlight.”
The report also suggests that the headlights of modern vehicles are now increasingly at odds with the Highway Code (rule 114) which states: “You must not use any lights in a way which would dazzle other road users.”
“Despite this, and US data showing that up to 15% of accidents are caused by glare from high-beam headlights, our government is deaf to the issue,” adds Hayter.
“It is not sustainable for the UK government and the car industry to deny there is a problem with modern vehicle headlights when the vast majority of motorists know that there is.”
New safety standards
The 26-page report urges the UK and other governments to develop and set realistic safety standards for vehicle headlights (and other vehicle lighting) and outlaw those that don’t achieve those standards.
Key issues it highlights include:
• Extreme brightness – the high luminance of LED chips commonly used in vehicle headlights causes discomfort and disability glare, increasing the risk of accidents as well as causing eye pain, headaches and migraine. This is a particular problem for older drivers but other drivers, cyclists and pedestrians are affected too.
• Flicker – although LEDs should not flicker (and most headlights do not) some retrofitted LEDs flicker badly when they are not compatible with vehicle electrical systems. Flicker causes disruption of eye movement (resulting in lower driver performance), headaches and migraines.
• Spectrum – LED vehicle headlights have a high colour temperature with a spike at the blue wavelength. This makes the headlights appear brighter than those of a similar brightness at a lower colour temperature. This also leads to blurred vision for older drivers who may be developing cataracts and people with certain eye conditions.
Incompatible with human eyesight
The report’s lead author, Dr John Lincoln of LightAware, said: “Many modern headlights are incompatible with dark-adapted human eyesight – particularly for older drivers. They are too bright, too blue and are blinding over too long a distance. Regulation is required to cut the risk of accidents and reduce driver fatigue.”
Hayter and representatives of organisations that worked on the report were due to meet with Department of Transport minister Lord Davies of Gower on 16 January to urge the government to undertake research and investigate the need to introduce appropriate standards on new tech and high spec headlights, including LEDs.
One of the country’s leading motoring organisations has also called on the government to commission an independent study into headlight glare after new research found 85% of those affected believe the problem is getting worse.
Survey highlights problem
An RAC survey of 2,000 drivers found that around 91% claimed they had been dazzled when driving, with three-quarters of these saying it happens regularly due to excessively bright headlights.
When it comes to the effects of glare, two in three drivers who suffer say they have to slow down until they can see clearly again, while a similar proportion believe some headlights are so bright they risk causing accidents.
Around 10% of those surveyed say they find headlight glare so bad that they avoid driving at night altogether, a figure that rises to 14% for drivers aged 65 and over.
According to the RAC, eight out of ten of its UK members think something should be done to reduce headlight glare, whilst in the United States thousands are signing a petition for action and organisations in Europe are also considering how to tackle the problem.
Blinded by the light
Excessively ultra-bright LED headlights are now installed as the de facto standard on every new car.
In the process, little thought has gone into the intense luminosity, blue-white colour balance, or the fact that LED light is acutely directional – more akin to a laser than a conventional light source – along with excessive glare, a huge increase in light intensity and a very sharp cut-off.
It seems our vehicle and lighting designers have run with the excitement and capacity of LED technology merely because it was new and the latest thing, without considering some of its adverse effects. We’re slowly learning that technology isn’t always what it’s cracked up to be.
