As used in this subchapter:
(1) “Employee” means any person currently employed, laid off with reemployment rights or on leave of absence. The term “employee” shall not include applicants for employment or designated agents.
(2) “Employer” shall mean any individual, person, partnership, association, corporation, the State, any of its political subdivisions or any agency, authority, board or commission created by them.
(3) “Personnel file” means, if maintained by the employer, any application for employment, wage or salary information, notices of commendations, warning or discipline, authorization for a deduction or withholding of pay, fringe benefit information, leave records, employment history with the employer, including salary information, job title, dates of changes, retirement record, attendance records, performance evaluations and medical records. The term “personnel file” shall not include records of an employee relating to the investigation of a possible criminal offense, letters of reference, documents which are being developed or prepared for use in civil, criminal or grievance procedures or materials which are used by the employer to plan for future operations or information available to the employee under the Fair Credit Reporting Act [15 U.S.C. § 1681 et seq.].