5 C.F.R. § 511.613
Appeals reconsideration by the Office
The Office may, at its discretion, reopen and reconsider a certificate issued under this subpart.
(a) Requests which contain new and material information, or disagreements over the significance of information, will be remanded to the Director's designee for a decision.
(b) The Office may reopen and reconsider a decision only when written argument or evidence is presented which establishes a reasonable doubt concerning the technical accuracy of the decision.