5 C.F.R. § 310.102
Subsection (d) of 5 U.S.C. 3110 authorizes the Office of Personnel Management to prescribe regulations authorizing the temporary employment of relatives, in certain conditions, notwithstanding the restrictions. This regulation sets forth exceptions to the restrictions. When necessary to meet urgent needs resulting from an emergency posing an immediate threat to life or property, or a national emergency as defined in § 230.402(a)(1) of this title, a public official may employ relatives to meet those needs without regard to the restrictions on the employment of relatives in 5 U.S.C. 3110 . Such appointments are temporary and may not exceed 30 days, but the agency may extend such an appointment for one additional 30-day period if the emergency need still exists at the time of the extension.
5 C.F.R. §310.102