Highway Code Rule 269

Hard shoulder. You MUST NOT use the hard shoulder for overtaking. In areas where an Active Traffic Management (ATM) Scheme is in force, the hard shoulder may be used as a running lane. You will know when you can use this because a speed limit sign will be shown above all open lanes, including the hard shoulder. A red cross or blank sign above the hard shoulder means that you MUST NOT drive on the hard shoulder except in an emergency or breakdown. Emergency refuge areas have also been built into these areas for use in cases of emergency or breakdown.

Laws

Rule 269: Overhead gantry showing red cross over hard shoulder
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