21. In this Schedule—
(a)“design pressure” means the gauge pressure in Bar chosen by the manufacturer and used to determine the thickness of the vessel's pressurised parts;
(b)“inspection slip” means the document by which the producer of the materials certifies that the products delivered meet the requirements of the order and in which the producer sets out the results of the routine in-plant inspection test, in particular chemical composition and mechanical characteristics, performed on products made by the same production process as the supply, but not necessarily on the products delivered.
(c)“Ph” means hydrostatic or pneumatic test pressure in Bar.