Out of Service Tank Inspection at Equity Industrial Partners

CommTank provided an out-of-service inspection of a 350,000-gallon aboveground storage tank (AST) containing water for a fire suppression system in Braintree, MA. This facility was recently acquired by the Equity Industrial Partners and they wanted the system inspected before placing it in service. The inspection was conducted in accordance with NFPA 25 Standard for the Inspection, Testing, and Maintenance of Water-Based Fire Protection Systems.

CommTank completed the tank cleaning and inspection utilizing a three-person crew in 3 days. The inspection was directed by a certified aboveground storage tank Inspector to insure the thoroughness of the examination and make recommendations as required.

Vacuum box testing on AST floor welds

The following is a summary of the steps required to perform the out-of-service water tank inspection.

  • Removed and disposed non-pumpable tank bottoms to allow access to tank floor.
  • Cleaned inner tank walls with absorption pads to remove residual fluids.
  • Removed old burner coil from inside the AST.
  • Visually inspected the floor, shell, roof, and interior structural supports.
  • Ultrasonic thickness measurements of the tank floor were performed in order to identify underside corrosion. These measurements concentrated on the critical shell to floor zone and radiated to the center of the tank. Special emphasis was focused on the internal sump components.
  • Ultrasonic thickness measurements were performed on the tank vertical shell.
  • Ultrasonic thickness measurements were also obtained on the roof.
  • Vacuum box testing was performed on all tank floor lap welds and bottom-to-shell welds.
  • A detailed outcome report signed by a certified inspector was prepared documenting the results of the inspection. This included recommendations concerning immediate repair requirements, overall condition assessment, suitability for continued services, as well as recommendations concerning re-inspection intervals.

Fire suppression water storage tank