The validity period of the domestic navigation certificate ① The validity period of the "Certificate of Airworthiness for Passenger Ships" shall not exceed 2 years; ② The validity period of safety certificate of high-speed ship, airworthiness certificate of cargo ship, ship load line certificate, oil pollution prevention certificate and domestic sewage pollution prevention certificate shall not exceed 5 years; ③ "Ship Tonnage Certificate" is generally valid for a long time.

At the expiration of the certificate renewal inspection, if the ship is not at the port scheduled for inspection, the certificate may be extended for no more than 3 months if the ship inspection agency considers it just and reasonable. After the overdue ship arrives at the port scheduled for inspection, it can no longer sail and must be inspected with a new certificate. The certificate after the replacement inspection shall take effect from the date of completion of the replacement inspection, and its validity period shall not exceed 5 years from the date of expiration of the certificate before the replacement inspection.