Steel cylinders containing inert gas shall be inspected every five years; Steel cylinders containing corrosive gases, submersible cylinders and steel cylinders often in contact with seawater shall be inspected every two years; Steel cylinders containing other gases shall be inspected every three years.

In case of serious corrosion, damage or doubt on the safety and reliability of steel cylinders during use, they shall be inspected in advance.

Steel cylinders in stock or out of service for more than one inspection cycle shall be inspected before use.

Steel cylinders with a service life of more than 30 years will be scrapped and will not be inspected after registration.