The right to compensation under this title is barred unless a claim is filed with the commission within two years after an accident, or if death resulted from the accident, within two years of the date of death. However, for occupational disease claims the two-year period does not begin to run until the employee concerned has been diagnosed definitively as having an occupational disease and has been notified of the diagnosis. For the death or injury of a member of the South Carolina National Guard, as provided for in § 42-7-67, the time for filing a claim is two years after the accident or one year after the federal claim is finalized, whichever is later. The filing required by this section may be made by registered mail, and the service within the time periods set forth in this section constitutes timely filing. For a "repetitive trauma injury" as defined in § 42-1-172, the right to compensation is barred unless a claim is filed with the commission within two years after the employee knew or should have known that his injury is compensable but no more than seven years after the last date of injurious exposure. This section applies regardless of whether the employee was aware that his repetitive trauma injury was the result of his employment.