Vehicle Headlight Glare Standards

Debate between Simon Lightwood and Lauren Edwards

Wednesday 29th October 2025 Westminster Hall

[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.

[Lauren Edwards]

Given that SUVs, which are generally larger, higher cars and have LED lights, now make up more than half of new cars sold in the UK and demand is growing, does the Minister agree that it is critical that the Government address this issue urgently?

[Simon Lightwood]

I heed the comments of my hon. Friend. Again, it is important that we are evidence-led, hence the commissioning of further research to drill down on the cause and effect.

In parallel, the Driver and Vehicle Standards Agency, which leads for the Department on market surveillance of vehicles and automotive components, has stepped up its activities to intercept the sale of illegal retrofit headlamp bulbs for on-road use, which we believe is one of the contributing factors. Anyone caught could face a fine of £1,000. The Department is also an active member of the Euro NCAP consumer information programme, which assesses a range of vehicle characteristics to determine a vehicle’s safety rating. Work is under way to develop a new vision protocol for 2029, which is planned to include an assessment of vehicle lighting systems to ensure that they provide forward vision while minimising the risk of dazzle for some road users.

Much has already been achieved, but we have listened and we understand that more can and must be done. We will continue to develop the evidence and work domestically and with our international partners to help ensure that people feel able to drive at night without experiencing glare or dazzle.