AST Inspection Certification Frequencies Instructions

This calculator is designed to assist tank owners in determining their fit/not-fit inspection certification frequencies. In order to use this calculator you must know the date that the tank was registered with the DEP and have Microsoft Excel. Please read this entire document and follow the instructions below.

  1. Go to the Inspection Frequency Calculator by clicking here and enter the date your tank was registered in the blank space at cell D8 of the Excel spreadsheet. (month/day/year)
    Note: do not enter the tanks install date but the date that it was registered with the DEP.

  2. After entering the registration date an inspection frequency for the tank will be calculated based on tank level. Both calculations for level 1 and level 2 tanks are visible. Please determine your tank level and review the appropriate column.

    The inspection frequency for level 1 tanks starts in cell D11 through D23. A PE, API certified or STI certified tank inspector must certify the tank every three (3) years with owner certifications required in the intervening years.

    The inspection frequency for level 2 tanks starts in cell F11 through F23. A PE, API certified or STI certified tank inspector must certify the tank every five (5) years with owner certifications required in the intervening years.

    If it has been determined by the DEP that your tank is register and label (RL), inspection certifications are not required.

    If you are unsure what level your tank is please log-on to the DEP’s Electronic Submission System and review your application.

Additional Notes Regarding AST Certifications


If your tank was properly inspected and certified pursuant to the interpretive rule (47 CSR 62) it will be considered to have met the initial inspection requirements of 47 CSR 63, effective 08/01/2016. If this is the case your next inspection will be owner certified and is due on or before 1/1/2018. Please follow the inspection frequency as calculated from this date forward. This applies to all level 1 and level 2 tanks that were properly certified pursuant to the interpretive rule.

If your tank was not properly inspected and certified pursuant to the interpretive rule (47 CSR 62) your initial inspection is due on or before 1/28/2017 by a PE, API certified or and STI certified tank inspector. This applies to all level 1 and level 2 tanks not properly certified pursuant to the interpretive rule.

For new installs registered after 1/28/2017, or after the 1st of any following year, initial inspections conducted by a PE, API certified or STI certified tank inspector will be due on or before the first day of the following year. This is regardless of tank level. Please follow the inspection frequency as calculated from this date forward based on the DEP determined tank level.

For further guidance on inspection certification please visit the DEP’s web page here.

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