1. Subject to the provisions of subregulation (2), no user shall use, require or permit the use of any vessel under pressure unless-
a. it has been designed and constructed in accordance with a health and safety standard incorporated into these regulations in terms of section 44 of the Act;
b. it has been manufactured under the supervision of an approved inspection authority as contemplated in regulation 17(1)(a) or any other inspection authority outside the Republic recognised by the chief inspector; and
c. the user is in possession of a certificate of manufacture issued by the manufacturer in which it is certified that the boiler, pressure vessel or portable gas container has been designed, constructed and tested in every respect in accordance with the standard contemplated in subregulation (1)(a): Provided that such a certificate shall be countersigned by the approved inspection authority as evidence that the design of such a boiler, pressure vessel or portable gas container has been verified and that it has been constructed and tested under their supervision in accordance with the said standard.
2. The certificate required by subregulation (1)(c) in the case of a pressure vessel or portable gas container may refer to more than one pressure vessel or portable gas container: Provided that each pressure vessel or portable gas container has the same design pressure and dimensions, and that the product of the design pressure in Pascals and the volume in cubic meters of that vessel does not exceed the figure 500 000.