6.—(1) Non-alloy aluminium must have an aluminium content of at least 99.5% and the alloys referred to in regulation 2(1)(b) (interpretation) must display adequate resistance to intercrystalline corrosion at maximum working temperature.
(2) Moreover, these materials must satisfy the following requirements—
(a)they must by supplied in an annealed state;
(b)they must have the following mechanical characteristics per product—
(i)the maximum tensile strength Rm, max must be no more than 350 N/mm2,
(ii)the elongation after fracture must be—
(aa)A ≥ 16% if the test piece is taken parallel to the direction of rolling;
(bb)A ≥ 14% if the test piece is taken perpendicular to the direction of rolling.