For the purpose of this part—

(a) Acceptable performance means performance that meets an employee's performance requirement(s) or standard(s) at a level of performance above “unacceptable” in the critical element(s) at issue.

(b) Critical element means a work assignment or responsibility of such importance that unacceptable performance on the element would result in a determination that an employee's overall performance is unacceptable.

(c) Current continuous employment means a period of employment or service immediately preceding an action under this part in the same or similar positions without a break in Federal civilian employment of a workday.

(d) Opportunity to demonstrate acceptable performance means a reasonable chance for the employee whose performance has been determined to be unacceptable in one or more critical elements to demonstrate acceptable performance in the critical element(s) at issue.

(e) Reduction in grade means the involuntary assignment of an employee to a position at a lower classification or job grading level.

(f) Removal means the involuntary separation of an employee from employment with an agency. P>(g) Similar positions mean positions in which the duties performed are similar in nature and character and require substantially the same or similar qualifications, so that the incumbents could be interchanged without significant training or undue interruption to the work.

(h) Unacceptable performance means performance of an employee that fails to meet established performance standards in one or more critical elements of such employee's position.