Section 10(g) in The Manual of Departmental Orders
(g)The communication of adverse comments to an Engineer Officer should be made by means of a personal letter marked "Confidential" and addressed direct to him, a copy of each such letter being attached to the annual report in question. Reporting officers will be at liberty, however, to call up any official in whom they have reported adversely and to inform him of the adverse remarks, if they consider that he is likely to benefit thereby.
