Annual Chemical Tank Inspection

Maintaining your tank is important in ensuring that the optimum life of the tank is achieved and that the risk of any unexpected leaks is reduced.

The guidelines below will help achieve the maximum tank life.

WARNING: Failure to follow these inspection guidelines and take necessary corrective actions can result in unintended chemical release.

Even relatively new polyethylene tanks should receive routine and careful visual inspections. These inspection guidelines should be followed at least annually to ensure the safety of personnel and the preservation of the chemical stored. The tank should be replaced if it displays stress cracking, crazing, or embrittlement.

  • Empty the tank. Neutralise any chemical remaining. Thoroughly clean the exterior of the tank.
  • When a confined space entry is possible, thoroughly clean the interior of the tank.
  • A dirty tank cannot be properly inspected.
  • Examine the exterior and the interior of the tank for cracking, crazing, and brittle appearance.
  • Pay particular attention to areas around any fittings. Give special attention to “corners” where sidewall and roof meet and where sidewall and bottom floor meet.
  • If a confined space entry is not feasible, use a bright light source to inspect the tank interior from the manhole opening. An interior inspection is essential because stress cracks normally show up on the inside of a tank before appearing on the outside.
  • DO NOT STAND OR WORK ON TOP OF TANK. The tank surfaces are flexible and slippery and a dangerous fall could occur. Remember – Safety First
  • Don’t forget to inspect areas of the tank that never actually come in contact with the chemical stored. With fume-emitting chemicals, oxidation and the embrittlement of the roof can occur without any actual contact with the chemical stored.
  • Inspect fittings, sight glass connections, flexible couplings, flexible connection hoses, and gaskets for leaks and signs of general corrosion or deterioration. For additional information on flexible connections refer to our guide Flexible Connections
  • Inspect vents to ensure adequate venting for pressure and vacuum.
  • Confirm that filling of the tank via the fixed fill port does not cause over pressurisation within the tank.
  • Confirm secondary containment bund is appropriate for chemical stored and has been maintained in good condition.


Chemical fumes may be present in the area of the manhole opening.

A tank is a confined space. Do not enter any tank without Confined Space Entry training and a permit.

Use lift equipment and/or fall protection to prevent fall into or away from tank.

Do not stand or work on top of tank. Roof surfaces can be flexible and slippery. If the tank has had long term sunlight exposure and/or internal oxidisation attack the roof may be embrittled and a failure of the roof could occur with the weight of a person standing on the roof.