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HMRC internal manual

Employment Income Manual

Deductions from earnings: capital allowances: meaning of "machinery or plant"

There is no statutory definition of what constitutes “plant”. Broadly speaking, to qualify as “plant” an item must have a working life of at least two years (see CA21100).

If an item does not qualify as plant or machinery you will need to consider whether a deduction is due under the general rule for employees’ expenses in Section 336 ITEPA 2003 (see EIM31600 onwards and EIM36510).