NEN EN 12820 : 2002

Foreword
Introduction
1 Scope
2 Terms and definitions
3 Safety
  3.1 Safety precautions
  3.2 Unsafe conditions
  3.3 Leaks
4 Written scheme
5 Tank inspection and requalification
  5.1 Routine inspection
  5.2 Periodic inspection
  5.3 Requalification
6 Inspection of tank and tank fittings
  6.1 Tank
  6.2 Tank fittings and immediate pipework
  6.3 Valve cover
  6.4 Bonding
  6.5 Pressure relief valves
  6.6 Pressure gauge
  6.7 Contents gauges
  6.8 Shut-off valves
  6.9 Studs, bolts, nuts, and washers
  6.10 Emergency valves
  6.11 Gaskets
  6.12 Pressure switch
  6.13 Temperature gauge
  6.14 Remotely operated valves
  6.15 Corrosion protection system
7 Site inspection
  7.1 Storage site
  7.2 Warning notices
8 Competence
  8.1 Routine inspection
  8.2 Periodic inspection
  8.3 Requalification
9 Records
  9.1 Tank data
  9.2 Reports
Annex A (informative) Internal visual inspection
        A.1 General
        A.2 Inspection techniques
        A.3 Records
        A.4 Additional inspection
Annex B (informative) Hydraulic pressure test
Annex C (informative) Acoustic emission testing
        C.1 General
        C.2 Safety precautions
        C.3 Acceptance criteria
Annex D (informative) Ultrasonic thickness test
        D.1 General
        D.2 Apparatus setting
        D.3 Control measurement
        D.4 Shell thickness measurements
        D.5 End thickness
        D.6 Interpretation
        D.7 Rejection criteria
Annex E (informative) Monitoring cathodic protection with
        sacrificial anodes
        E.1 General
        E.2 Records
        E.3 Procedure
        E.4 Measurement of the galvanic current
        E.5 Measurement of the potential difference of the
            tank to earth
        E.6 Results
Annex F (informative) Monitoring cathodic protection by
        impressed current
        F.1 General
        F.2 Apparatus
        F.3 Conditions
        F.4 Isolation resistance of the coating
            F.4.1 Procedure
            F.4.2 Calculation
        F.5 Results
        F.6 Checking intervals
Annex G (informative) Example of a report
Annex ZA (informative) A-deviations

Gives requirements for routine inspection, periodic inspection and requalification of underground and mounded LPG storage tanks of sizes greater than 13 m[3], and associated fittings; marking tanks and/or keeping records, as appropriate, as a result of routine inspection, periodic inspection and requalification