AIR PUMP Act This bill gives an air carrier crewmember the right to break time and a private space to express breast milk at work. Exceptions to this right apply during a critical phase of flight, if it impacts the safety of an aircraft, or if it would impose a significant expense. An employer may not discriminate or retaliate against an employee who testifies in a proceeding or files a complaint related to this bill. The bill provides for enforcement by the Department of Labor or in a private lawsuit. The Federal Aviation Administration must issue regulations.