29 C.F.R. § 2200.68

(a) Discretionary recusal. A Judge may recuse themself from a proceeding whenever the Judge deems it appropriate.

(b) Mandatory recusal. A Judge shall recuse themself under circumstances that would require disqualification of a Federal judge under Canon 3(C) of the Code of Conduct for United States Judges, except that the required recusal may be set aside under the conditions specified by Canon 3(D).

(c) Request for recusal. Any party may request that the Judge, at any time following the Judge's designation and before the filing of a decision, be recused under paragraph (a) or (b) of this section or both by filing with the Judge, promptly upon the discovery of the alleged facts, an affidavit setting forth in detail the matters alleged to constitute grounds for recusal.

(d) Ruling on request. If the Judge finds that a request for recusal has been filed with due diligence and that the material filed in support of the request establishes that recusal either is appropriate under paragraph (a) of this section or is required under paragraph (b) of this section, the Judge shall recuse themself from the proceeding. If the Judge denies a request for recusal, the Judge shall issue a ruling on the record, stating the grounds for denying the request, and shall proceed with the hearing, or, if the hearing has closed, proceed with the issuance of a decision under the provisions of § 2200.90.