45 C.F.R. § 81.115
A request for information which merely inquires about the status of a proceeding without discussing issues or expressing points of view is not deemed an ex parte communication. Such requests should be directed to the Civil Rights hearing clerk. Communications with respect to minor procedural matters or inquiries or emergency requests for extensions of time are not deemed ex parte communications prohibited by § 81.113 . Where feasible, however, such communications should be by letter with copies to all parties. Ex parte communications between a respondent and the responsible Department official or the Secretary with respect to securing such respondent's voluntary compliance with any requirement of part 80 of this title are not prohibited.
45 C.F.R. §81.115