(a) By personal delivery or by mail, written notice of an accidental injury shall be given by the person injured or someone in his behalf to the employer or any of his agents within 48 hours after the injury. In the case of an occupational disease notice shall be given by the person injured or someone in his behalf to the employer or any of his agents within 30 days from the first distinct manifestation thereof. Such notice shall contain the name of the person, the nature of the injury or occupational disease, and when and where it occurred. Unless written notice of injury or occupational disease is given as above, or unless the employee's immediate superior has actual knowledge of the injury or occupational disease, compensation may be denied. For reasonable cause shown, the Administrator may accept written notice of injury given later than 48 hours, but not later than 30 days, after the injury and in the case of an occupational disease, the Administrator may accept written notice given later than 30 days, but not later than 90 days after the first distinct manifestation thereof; which time limit for filing of reports shall also be applicable to injuries of a tuberculous origin arising out of employment.
(b) Within eight days after the receipt of the written notice of injury referred to in subsection (a) hereof, the employer shall complete an employer's report of injury and forward same together with the employee's notice of injury to the Administrator by personal delivery or by mail. The failure of the employer to file such reports within such period shall not prejudice the claim of the employee.