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HMRC internal manual

Employment Income Manual

Other expenses: dirty money

“Dirty money” is additional taxable pay for working in unpleasant conditions, see EIM01080. A request by an employee who is receiving dirty money for an additional expense deduction as a result should be considered on its merits. All of the conditions in Section 336 ITEPA 2003 must be met, see EIM31630.

It does not necessarily follow that an employee who is receiving dirty money will have incurred any additional deductible expense as a result. For example, an employee who wears his or her own clothes to work is not permitted a deduction for the cost of washing those clothes simply because they may get unusually dirty, see EIM32480.