A certificate under section 6AA of the Act may be issued by a person who—
(a) is a full member of the Institution of Civil Engineers, or a corporate member of the Institution of Structural Engineers or is authorised by the appropriate designated authority in accordance with the European Communities (Recognition of Professional Qualifications) Regulations 1991( ) to practise the profession of chartered civil engineer or chartered structural engineer in the United Kingdom;
(b) produces to the local authority adequate documentary evidence that he meets the criteria specified in paragraph (a) above; and
(c) has himself prepared the necessary design calculations in respect of the building in question or is satisfied that such calculations have been properly prepared.