5 CFR 831.1111: Appeal and review.

(a) An appeal from an initial decision, or a decision of the Associate Director under § 831.1105(b), may be made to OPM, with service on the other party, within 30 calendar days from the date of the decision. An appeal shall be in writing and shall state plainly and concisely the grounds for the appeal, with a specific reference to the record when issues of fact are raised. The other party may file an opposition to the appeal within 15 days after service on him. On notice to the parties, OPM may extend the time limits prescribed in this paragraph.

(b) Within 30 calendar days from the date of an initial decision or a decision of the Associate Director, OPM, on its own motion, may direct that the record be certified to it for review.