Vehicle Headlight Glare Standards

Shockat Adam Excerpts

Wednesday 29th October 2025 Westminster Hall

[Shockat Adam (Leicester South) (Ind)]

It is an absolute pleasure to serve under your chairmanship, Mrs Harris. I thank the hon. Member for Crawley (Peter Lamb) for bringing this debate to Westminster Hall. I declare that I have personal experience with this issue as a practising NHS optometrist, so I can say with some clarity that it is of great importance and concern, with potentially significant consequences. Many of my patients have told me of their utter despair when they want to drive at night. Some only take the keys out if it is a real emergency, while others have abandoned it altogether, which feeds into the narrative that elderly people in particular will not go shopping or go to the pharmacist to pick up medication. That can result in loneliness and other problems.

There are also those who continue to drive despite knowing that night driving is really difficult for them. That becomes a matter of life and death, as some of the statistics bear out. As an optometrist, I have only anecdotal evidence, but although excellent research has been done by the College of Optometrists, the Association Of Optometrists and the RAC, among others, it does not take an expert to know the link between eyesight and safety for everyone who uses the road.

I want to focus on two intertwined challenges: the impact of modern car lighting, and the lack of research and subsequent legislation around it, and the failure of our system to ensure that drivers meet basic vision standards.

Modern vehicles are brighter than ever. LED and xenon technologies have replaced many older halogen bulbs. They are much brighter and more efficient, and provide better clarity on the road for the driver, but unfortunately the increased brightness comes at a cost, which is a rise in glare and dazzle for other road users. The RAC, drawing on Government collision statistics, reported that since 2013, an average of 280 crashes a year in Britain have involved dazzling headlights as a contributing factor. Six of those crashes a year involve a loss of life. Campaigners believe that the real figures could be a lot higher.

The shift from halogen to LED, combined with higher headlight positioning because of SUV cars, is part of the problem. Experts at the light and health research centre at Mount Sinai hospital in New York have identified three factors driving the problems: the rise of taller vehicles, incorrect alignment of lights and the blue light of modern LED bulbs. Due to their shorter wavelength, they can potentially scatter more light in the eyes, and are more uncomfortable than other light forms. No research, as far as I am aware—there have been some anecdotal studies and very small-scale studies, but nothing conclusive—confirms that they help night driving.

The RAC also found that it takes 68% of drivers—this is really worrying—up to five seconds to recover after they have been dazzled, and more than 11% say that it takes six seconds or more. That is the time it takes to travel 160 metres at 60 miles per hour, without any clear vision. That is worse for anyone who has other eye health conditions, such as corneal opacity at the front of the eyes, cataracts or macular degeneration problems, but also a dirty windscreen or glasses lenses.

The greater, and quieter, threat is the number of drivers who already have poor or unsafe vision and continue to drive anyway. According to statistics by Mortar in October 2024, one in seven people knows of a relative, friend or co-worker who they believe is breaking the law by driving despite poor eyesight. Almost 30% of motorists admitted they would continue to drive even if they knew their vision was below the legal standards. More than a quarter said they are worried about someone they know who drives despite having poor vision.

These figures are deeply concerning, and reveal that our current, self-referral system is failing and many people either do not know their vision has declined or choose to ignore it. Earlier this year, a coroner in Lancashire issued a prevention of future death report following a fatal crash caused by undiagnosed sight loss. We need to change the legislation and have more research done on lighting.

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[The Parliamentary Under-Secretary of State for Transport (Simon Lightwood)]

It is a pleasure to serve with you in the Chair, Mrs Harris. I start by congratulating my hon. Friend the Member for Crawley (Peter Lamb) on securing this debate about the potential merits of a new standard for headlight glare. I am sure that it will have not gone unnoticed that the UK has some of the safest roads in the world. But the effect of every death or injury on our roads is devastating for the individuals and families involved.

I make it clear that this Government treat road safety seriously and are committed to reducing the number of those killed and injured on our roads. The Department is working to develop its road safety strategy, which will include a broad range of policies, and will set out more detail in due course. More widely, the Department recognises the importance of the road network to many people’s lives and to the economy. But we know that not everyone shares the same positive experience. Glare from headlamps is a perennial issue, as there is a compromise between providing illumination with sufficient intensity and distance to enable drivers to see and anticipate potential hazards, and the propensity to cause glare for other road users.

To strike the right balance, all vehicle headlamps are designed and tested to follow international standards developed under the United Nations to ensure that they are bright enough to illuminate the road but do not unduly affect the vision of other road users. Those standards define the beam pattern and include maximum and minimum light intensities. None the less, we know that lots of people raise concerns about headlamp glare, and we are told that some drivers, as has been mentioned, choose not to drive at night because of its effects. While police collision statistics do not indicate an increase in collisions caused by headlamp glare, the issue can lead to social isolation, which impacts on people’s wellbeing and their ability to undertake everyday tasks.

My hon. Friend the Member for Crawley highlighted the impact on older residents in particular. Obviously, we have an ageing population with increasing numbers of older drivers. As people age, their eyes become more susceptible to glare due to changes in the photobiology of their eye. Better vehicle technology such as power-assisted steering, automatic transmission and improved braking and parking aids have made the driver’s task easier, and people tend to drive for longer before surrendering their licence. The number of adults more than 70 years old in England holding a full car licence has actually increased by more than 50% over the last 10 years.

[Shockat Adam]

I agree wholeheartedly that better cars mean that we are driving for longer, but does the Minister share my concern that the UK is the only country in Europe that allows people to hold a driving licence until the age of 70 without ever being required to take a sight test? Perhaps we need a sight test at initial licence application, at every 10-year renewal and at every three years from the age of 70 because we are driving for much longer.

[Simon Lightwood]

We will always keep all these considerations under review, but, as with anything, we will be evidence-led on the measures that we put in place, working with our international partners.

Road users will have experienced discomfort from headlamp glare when driving. From personal experience, I know that that is not pleasant. A few Members raised headlight aim, which is checked in an MOT once a year. During normal wear and tear, headlights can become out of alignment. The manual controls that many of us have to adjust our headlight focusing need to be changed if we have passengers in the back seats or luggage in the boot. Many Members I spoke to in advance of the debate did not know that, if they have luggage in their boot or people in the back seats, they should adjust their headlights. There is more education to be done there.

Over the years, the Department for Transport has raised the issue at the United Nations international expert group on vehicle lighting, and it was asked about the UK playing an international role. Following lengthy and significant negotiations, proposals to amend headlight aiming rules were agreed in April 2023, together with requirements for mandatory automatic headlamp levelling —a system that automatically recorrects the aim of the headlights based on the loading of the vehicle, to go back to the issue of when passengers are in the back seats or there is luggage in the boot. Those new requirements are expected to take effect in September 2027, to permit sufficient time for vehicle manufacturers to redesign their products and adapt the manufacturing process. Once implemented, those tougher requirements will help alleviate the number of cases where road users feel dazzled by vehicle headlamps.

There is, however, still much to do and much that we do not know about the underlying causes. To address the lack of clear evidence into which factors are impacting on drivers, the Department for Transport commissioned independent research in 2024 to understand better the root causes of the glare. Over several months, researchers gathered real-world glare data when driving at night, using an instrumented vehicle and machine learning analysis tools to determine the main factors that influence glare. That work was recently completed, and the final report is due to be published in the next week.

As might be expected, the results indicated that road geometry, in combination with brightness, is a key factor in glare events. The second most important factor, however, was identified to be vehicle type, suggesting that certain vehicle characteristics may be contributing to problems of glare. Given the findings of this innovative and groundbreaking research, the Department plans further research examining a range of vehicle makes and models, aimed at identifying what vehicle design factors may be responsible for increased glare. That can then be used to generate proposals for amendments to the international vehicle lighting regulations at the United Nations.