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HMRC internal manual

Employment Income Manual

Travel expenses: travel for necessary attendance: emergency call-out and stand-by: emergency call-out: example

An employee is required to be a keyholder for her permanent workplace. One night she is called out by the police responding to a burglar alarm. No deduction is due for the cost of travel between her home and her permanent workplace.

The travel is ordinary commuting, see EIM32055. It does not cease to be ordinary commuting because it is not made during her ordinary working hours, see EIM32240.