4.—(1) Every water fitting shall–
(a)be of an appropriate quality and standard; and
(b)be suitable for the circumstances in which it is used.
(2) For the purposes of this regulation, a water fitting is of an appropriate quality or standard only if–
(a)it bears an appropriate CE marking in accordance with the Directive;
(b)it conforms to an appropriate harmonized standard or European technical approval;
(c)it conforms to an appropriate British Standard or some other national specification of an EEA State which provides an equivalent level of protection and performance; or
(d)it conforms to a specification approved by the regulator.
(3) Every water fitting shall comply with the requirements of Schedule 2 to these Regulations as it applies to that fitting.
(4) Where any requirement of Schedule 2 relates to a water system, every water fitting which forms part of that system shall be fitted or, as the case may be, altered or replaced so as to comply with that requirement.
(5) Every water fitting shall be installed, connected, altered, repaired or disconnected in a workmanlike manner.
(6) For the purposes of this regulation, a water fitting is installed, connected, altered, repaired or disconnected in a workmanlike manner only if the work is carried out so as to conform–
(a)to an appropriate British Standard, a European technical approval or some other national specification of an EEA State which provides an equivalent level of protection and performance;
(b)to a specification approved by the regulator; or
(c)to a method of installation approved by the water undertaker.