Section 40(2)(B) in The Orissa Municipal Employees' Pension Rules, 1989
(B)Pension-(i)The entitlement to monthly pension shall accrue in case of a retired employee who at the time of retirement has completed 20 half-yearly period of more of qualifying service.(ii)The maximum period of qualifying service to be taken into account for the purpose of pension shall be limited to 66 half-yearly period.