The powers of the Director General of Audit relating to technical matters are derived from the Manual of Standing Orders (Audit) - (Paras 1.1.19 and 1.1.20), and those relating to the scope and extent of audit are detailed in the Secret Memorandum of Instructions and the orders issued by the Comptroller and Auditor General of India from time to time. Director General of Audit may relax the prescribed extent of audit as laid down in para 3 Chapter I of the Secret Memorandum of Instructions (Railways)for the reasons specified therein. The Director General of Audit has been declared as the "Head of the Department" for purposes of exercising powers under Fundamental Rules, Supplementary Rules and General Financial Rules. The financial and administrative powers of the Director General of Audit are given in Comptroller and Auditor General's Manual of Standing Orders (Administrative) Volume II.