(a) Candidates who have qualified but have not been appointed because of lack of vacancies will be dropped from the rank-order register 30 months after the date of the written examination: Provided, however, That reasonable time spent in civilian Government service abroad (to a maximum of 2 years such service), including service as a Peace Corps volunteer, in required active military service, or in required alternative service, subsequent to establishing eligibility for appointment will not be counted in the 30-month period.
(b) The Chairman of the Board of Examiners may extend the eligibility period when such extension is, in his judgment, justified in the interests of the Service. The Chairman shall report the approved extensions to the Board of Examiners. (22 U.S.C. 1221 et seq.) [37 FR 19356, Sept. 20, 1972]