An employee shall be entitled to a total of 12 administrative workweeks of unpaid leave during any 12-month period for one or more of the following reasons:

The birth of a son or daughter of the employee and the care of such son or daughter;

The placement of a son or daughter with the employee for adoption or foster care;

The care of a spouse, son, daughter, or parent of the employee, if such spouse, son, daughter, or parent has a serious health condition; or

A serious health condition of the employee that makes the employee unable to perform any one or more of the essential functions of his or her position.

Any qualifying exigency arising out of the fact that the employee's spouse, son, daughter, or parent is a covered military member on covered active duty (or has been notified of an impending call or order to covered active duty) in the Armed Forces.

An employee must invoke his or her entitlement to family and medical leave under paragraph (a) of this section, subject to the notification and medical certification requirements in §§ 630.1207 and 630.1208. An employee may not retroactively invoke his or her entitlement to family and medical leave. However, if an employee and his or her personal representative are physically or mentally incapable of invoking the employee's entitlement to FMLA leave during the entire period in which the employee is absent from work for an FMLA-qualifying purpose under paragraph (a) of this section, the employee may retroactively invoke his or her entitlement to FMLA leave within 2 workdays after returning to work. In such cases, the incapacity of the employee must be documented by a written medical certification from a health care provider. In addition, the employee must provide documentation acceptable to the agency explaining the inability of his or her personal representative to contact the agency and invoke the employee's entitlement to FMLA leave during the entire period in which the employee was absent from work for an FMLA-qualifying purpose. An employee may take only the amount of family and medical leave that is necessary to manage the circumstances that prompted the need for leave under paragraph (a) of this section.

The 12-month period referred to in paragraph (a) of this section begins on the date an employee first takes leave for a family or medical need specified in paragraph (a) of this section and continues for 12 months. An employee is not entitled to 12 additional workweeks of leave until the previous 12-month period ends and an event or situation occurs that entitles the employee to another period of family or medical leave. (This may include a continuation of a previous situation or circumstance.)

The entitlement to leave under paragraphs (a)(1) and (2) of this section shall expire at the end of the 12-month period beginning on the date of birth or placement. Leave for a birth or placement must be concluded within this 12-month period. Leave taken under paragraphs (a)(1) and (2) of this section, may begin prior to or on the actual date of birth or placement for adoption or foster care, and the 12-month period, referred to in paragraph (a) of this section begins on that date.

Leave under paragraph (a) of this section is available to full-time and part-time employees. A total of 12 administrative workweeks will be made available equally for a full-time or part-time employee in direct proportion to the number of hours in the employee's regularly scheduled administrative workweek. The 12 administrative workweeks of leave will be calculated on an hourly basis and will equal 12 times the average number of hours in the employee's regularly scheduled administrative workweek. If the number of hours in an employee's workweek varies from week to week, a weekly average of the hours scheduled over the 12 weeks prior to the date leave commences shall be used as the basis for this calculation. Any holidays authorized under 5 U.S.C. 6103 or by Executive order and nonworkdays established by Federal statute, Executive order, or administrative order that occur during the period in which the employee is on family and medical leave may not be counted toward the 12-week entitlement to family and medical leave.

If the number of hours in an employee's regularly scheduled administrative workweek is changed during the 12-month period of family and medical leave, the employee's entitlement to any remaining family and medical leave will be recalculated based on the number of hours in the employee's current regularly scheduled administrative workweek.

Each agency shall inform its employees of their entitlements and responsibilities under this subpart, including the requirements and obligations of employees.

An agency may not put an employee on family and medical leave and may not subtract leave from an employee's entitlement to leave under paragraph (a) of this section unless the agency has obtained confirmation from the employee of his or her intent to invoke entitlement to leave under paragraph (b) of this section. An employee's notice of his or her intent to take leave under § 630.1207 may suffice as the employee's confirmation.