Section 17(a) in Bihar Engineering Service Rules, 1939
(a)When the Governor has decided that any vacancy or vacancies in the service shall be filled by promotion, the Chief Engineers will nominate for promotion of, officers from the Bihar Engineering Service, Class II, the nomination will be made by seniority and merit combined but more importance will be attached to merit. The officers nominated by the Chief Engineer shall be arranged in order of preference and the number should ordinarily be 50 per cent in excess of the number of vacancies to be filled.
