(a) Covered. Any employee of an agency who is not specifically excluded by another statute is covered by the Act. This includes any person who is:

(1) Defined as an employee in section 2105 of title 5, United States Code;

(2) A civilian employee appointed under other appropriate authority; or

(3) Suffered or permitted to work by an agency whether or not formally appointed.

(b) Not covered. The following persons are not covered by the Act:

(1) A person appointed under appropriate authority without compensation;

(2) A trainee;

(3) A volunteer; or

(4) A member of the Uniformed Services.