4.—(1) Where, after this Part comes into operation—
(a)an employee suffers personal injury in the course of his employment in consequence of a defect in equipment provided by his employer for the purposes of the employer's business; and
(b)the defect is attributable wholly or partly to the fault of a third party (whether identified or not),
the injury shall be deemed to be also attributable to negligence on the part of the employer (whether or not he is liable in respect of the injury apart from this paragraph), but without prejudice to the law relating to contributory negligence and to any remedy by way of contribution or in contract or otherwise which is available to the employer in respect of the injury.
(2) In so far as any agreement purports to exclude or limit any liability of an employer arising out of paragraph (1), the agreement shall be void.
(3) In this Article—
“equipment” includes any plant and machinery, vehicle, aircraft and clothing; and
“fault” means negligence, breach of statutory duty or other act or omission which gives rise to liability in tort in Northern Ireland.
(4) This Article binds the Crown to the full extent authorised or permitted by the constitutional laws of Northern Ireland and for the purposes of this Article persons in the service of the Crown shall be treated as employees of the Crown if they would not be so treated apart from this paragraph.