20 CFR § 335.2 - Manner of claiming sickness benefits.
(a) Forms required for claiming benefits. To claim sickness benefits for a period of inability to work due to an illness or injury, or in the case of a female employee, pregnancy, miscarriage, or childbirth, an employee must file the following forms:
(1) An application for sickness benefits at the beginning of each period of continuing sickness;
(2) A statement of sickness to accompany the employee's application;
(3) A claim for sickness benefits for each 14-day registration period during the employee's period of continuing sickness; and
(4) A supplemental doctor's statement, if the adjudicating office requests additional proof of the employee's inability to work.
(b) Mailing or delivering the forms. The forms required by paragraph (a) of this section may be mailed or delivered to any Board office. If the Board is satisfied that the employee is too sick or injured to execute the required forms, the Board may accept forms executed by someone in the employee's behalf. Instructions for completing and filing the forms are printed on the forms themselves.