Motorists in the UK are being warned they could be breaking the law when behind the wheel - and they may not know it. The RAC warns that driving in sunglasses that are too dark is dangerous. While sunglasses can be vital for reducing glare and helping drivers stay safe in bright conditions, the darkest lenses - those with the highest rating on the Visible Light Transmission (VLT) scale - can cut visibility too much and potentially make driving unsafe.
What the RAC says about dark lenses
The RAC explains: "This refers to shades in 'category four' which only let in a very small percentage of daylight. The category can be found on the label of the packaging."
Additionally, some tinted glasses may be unsuitable for driving as they can make it difficult to see in low light situations - which drivers could experience, for instance, during an unexpected thunderstorm when the light level drops dramatically.
Road Traffic Act and Highway Code - could you be breaking it?
Under Section 96 of the Road Traffic Act 1988, the RAC says it’s illegal to drive if your eyesight doesn’t meet the legal standard, with penalties including a fine and three points. That covers any situation where your vision is reduced - including wearing sunglasses that are so dark they stop you seeing clearly enough to meet the required standard.
Additionally, Rule 94 of the Highway Code advises against using tinted glasses, lenses, or visors at night. It also urges caution in conditions of poor visibility if they limit how well you can see. Both this Act and Rule means if sunglasses make it harder for a driver to spot hazards or other road users, it could be treated as careless driving, or in more serious cases, dangerous driving.
What sunglasses are best for driving?
The RAC advises: "Category three sunglasses are the best option for daytime driving, as they offer sun protection, but are not too dark to risk the safety of the driver and other road users. Category two, although not as dark, are also considered a good option for daytime driving, providing a good balance between glare protection and visibility."
While these can be good options, it warns motorists that "they should not be worn at night or in other low-light conditions." It adds that 'category one' sunglasses are designed for low levels of sunlight, and while they are legal for driving during the day, they only offer modest glare reduction.
It's not just the RAC that gives motorists advice. The AA explains: "All sunglasses should carry the CE mark and meet the European Standard BS EN 1836:2005."
A good quality anti-reflection coating is recommended, along with a hard coating to protect the lenses from scratches. Sunglasses with deep side arms can block side, or peripheral, vision and are not recommended for driving.
Can I be fined for wearing sunglasses while driving in the UK?
Yes. The AA stresses that if you're involved in a collision where using unsuitable eyewear that's "considered to be a contributing factor, you may be liable to prosecution".
Your sunglasses need to meet the requirements set out in the Highway Code. This means they must not be so dark that they stop you from seeing clearly, must not be tinted while driving at night or in otherwise poor visibility, must not make it difficult to see traffic signals clearly, and must not have any scratches or external damage that makes it difficult to see.
