A driver conducts a pre-MOT inspection on their car tyres to ensure full compliance with r… — UK Driving Theory Test

A driver conducts a pre-MOT inspection on their car tyres to ensure full compliance with road safety standards. Which of the following tyre conditions makes the vehicle illegal to drive on UK public roads?

A
A tyre showing superficial surface scuffing on the sidewall with no internal ply or cords exposed
A tyre with a tread depth of $1.4\text{ mm}$ across the central three-quarters of its breadth around the entire outer circumferenceAnswer
C
A tyre where the outermost shoulder has worn to $1.2\text{ mm}$ , while the central three-quarters maintains $2.0\text{ mm}$ of tread with no cords visible
D
A tyre whose measured pressure has increased by $0.2\text{ bar}$ after being driven continuously at high speed on a motorway

Answer

The tyre with a tread depth of

1.4\text{ mm}

across the central three-quarters of its breadth fails legal requirements because UK regulations mandate a minimum tread depth of at least

1.6\text{ mm}

throughout this continuous central zone.

Under UK road traffic law, car tyres must have a minimum tread depth of at least

1.6\text{ mm}

throughout a continuous band comprising the central three-quarters of the breadth of the tread and around the entire outer circumference. A tyre with only

1.4\text{ mm}

across this critical zone fails the legal requirement.

Step-by-Step Solution

Identify the statutory UK legal requirements for passenger car tyre tread depth.

UK law mandates a minimum tread depth of

1.6\text{ mm}

across a continuous band covering the central three-quarters of the breadth of the tread and around the entire outer circumference.

Sufficient tread depth is essential to clear surface water effectively and prevent loss of grip or aquaplaning.

Evaluate each inspection finding against UK roadworthiness and construction regulations.

A tyre measuring

1.4\text{ mm}

in the central three-quarters falls below the mandatory

1.6\text{ mm}

legal limit, rendering the vehicle unroadworthy and illegal to drive.

Failing to maintain the statutory minimum depth breaches Road Vehicles (Construction and Use) Regulations and incurs penalty points and fines.

Key Concept

UK Statutory Tyre Tread Depth and Roadworthiness Requirements

Estimated Time:1m 30s

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