48 C.F.R. §§ 1823.570-1
Employee in a sensitive position means a contractor or subcontractor employee who has been granted access to classified information; a contractor or subcontractor employee in other positions that the contractor or subcontractor determines could reasonably be expected to affect safety, security, National security, or functions other than the foregoing requiring a high degree of trust and confidence; and includes any employee performing in a position designated "mission critical" or performing mission-critical duties. The term also includes any applicant who is tentatively selected for a position described in this paragraph.
Mission Critical Space Systems means the collection of all space-based and ground-based systems used to conduct space missions or support activity in space, including, but not limited to, the crewed space system, space-based communication and navigation systems, launch systems, and mission/launch control.
Mission Critical Positions/Duties means positions or duties which, if performed in a faulty, negligent, or malicious manner, could jeopardize mission critical space systems and/or delay a mission.
Use, in violation of applicable law or Federal regulation, of alcohol includes having, while on duty or during a preemployment interview, an alcohol concentration of 0.04 percent by weight or more in the blood, as measured by chemical test of the individual's breath or blood. An individual's refusal to submit to such test is presumptive evidence of use, in violation of applicable law or Federal regulation, of alcohol.
48 C.F.R. §§1823.570-1