5 C.F.R. § 732.202
Waivers and exceptions to investigative requirements
(a) Waivers—(1) General. A waiver of the preappointment investigative requirement contained in section 3(b) of Executive Order 10450 for employment in a sensitive national security position may be made only for a limited period: (i) In case of emergency if the head of the department or agency concerned finds that such action is necessary in the national interest; and (ii) when such finding is made a part of the records of the department or agency.
(2) Specific waiver requirements. (i) The preappointment investigative requirement may not be waived for appointment to positions designated Special-Sensitive under this part.
(ii) For positions designated Critical-Sensitive under this part, the records of the department or agency required by § 732.202(a)(1) of this part shall show what decision was made on obtaining prewaiver checks, as follows: (A) The nature of the emergency precluded obtaining prewaiver checks; or (B) checks were initiated but not all responses were received within 5 days; or (C) checks made and favorably completed are listed.
(iii) The waiver restriction is optional for positions designated Noncritical-Sensitive under this part.
(iv) When waiver is authorized, the required investigation must be initiated within 14 days of placement of the individual in the position.
(b) Exceptions to investigative requirements. (1) Pursuant to section 3(a) of E.O. 10450, the following positions are exempt from the investigative requirements of E.O. 10450, providing that the employing agency conducts such checks as it deems appropriate to insure that the employment or retention of individuals in these positions is clearly consistent with the interests of the national security:
(i) Positions that are intermittent, seasonal, per diem, or temporary, not to exceed an aggregate of 180 days in either a single continuous appointment or series of appointments; or
(ii) Positions filled by aliens employed outside the United States.
(2) Other positions that OPM, in its discretion, deems appropriate may be made exempt based on a written request to OPM by the agency head in whose department or agency the positions are located.