The Simple Pressure Vessels (Safety) Regulations 1991

EC verification certificate

12.—(1) EC verification is the procedure whereby an approved body checks, and certifies by means of an EC verification certificate, that vessels conform with a relevant national standard or with the prototype by reference to which an EC type-examination certificate was issued.

(2) Verification is carried out on batches of vessels made available to the approved body by either the manufacturer or his authorised representative established in the Community. A “batch” for this purpose is up to 3,000 vessels of the same series.

(3) Application for a verification certificate must be accompanied by–

(a) a copy of the relevant EC certificate of adequacy or type-examination certificate, as the case may be; and

(b) the design and manufacturing schedule conforming with Schedule 3.

(4) A United Kingdom approved body to which such application is made shall satisfy itself–

(a) that the schedule contains all the required information; and

(b) that the vessels in the batch have been manufactured and checked in accordance with the schedule.

(5) The United Kingdom approved body shall also perform the following tests–

(a) test of the vessel itself: a hydrostatic test, or a pneumatic test of equivalent effect, on each vessel, at a pressure equal to 1.5 times the vessel’s design pressure (which is the gauge pressure chosen by the manufacturer and used to determine the thickness of the pressurised components); and

(b) test of weld quality: tests on longitudinal welds and, where different welding techniques are used for longitudinal and circular welds, equivalent tests repeated on the latter.

• Pneumatic tests under sub-paragraph (a) must be in accordance with safety procedures accepted in the country where they are carried out. Tests of weld quality under subparagraph (b) must be carried out on pieces taken, at the manufacturer’s option, from a representative production test piece or a vessel in the batch submitted.

(6) The following applies in the case where a vessel’s wall-thickness is determined by the experimental method, that is to say so as to enable the vessel to resist at ambient temperature a pressure equal to at least 5 times the maximum working pressure (as defined in regulation 2(1) above), with a maximum permanent circumferential deformation factor of 1 per cent. In that case the tests referred to in paragraph (5)(b) of this regulation are to be replaced by a hydrostatic test on 5 vessels taken at random from each batch submitted, in order to check that the maximum is not exceeded.

(7) If satisfied that the vessels conform with a relevant national standard or (as the case may be) with the relevant prototype, the United Kingdom approved body shall issue a verification certificate.

(8) If the United Kingdom approved body is not so satisfied and refuses to issue a verification certificate, it shall make known in writing to the applicant the reasons for the refusal.