API 1631 : 2001

1 SCOPE
2 REFERENCED PUBLICATIONS
3 OBJECTIVES, REQUIREMENTS AND SPECIFICATIONS OF THE
    INTERIOR LINING PROCESS
    3.1 Objectives
    3.2 Permit and Training Requirements
    3.3 Coating (Lining) Specifications
4 PREPARATION FOR OPENING THE TANK
    4.1 Safety Precautions
    4.2 Tank Isolation
    4.3 Removal of Liquid Product
    4.4 Removal of Flammable Vapors (Vapor-Freeing)
    4.5 Testing Flammable Vapor Concentration
5 TANK ENTRY
    5.1 Opening the Tank
    5.2 Preliminary Precautions
    5.3 General Toxicity and Health Considerations
6 PREPARATION OF THE TANK INTERIOR
    6.1 Sludge Removal
    6.2 Special Toxicity Considerations
    6.3 Tank Inspection
    6.4 Surface Preparation
7 APPLICATION OF LINING
    7.1 Steel Tanks
    7.2 Fiberglass Tanks
8 TANK CLOSING
    8.1 Steel Tanks
    8.2 Fiberglass Tanks
    8.3 Tank Tightness Testing
Figures
1 Eductor-Type Air Mover
2 Diffused Air Blower
3 Method for Installation of Tank Cover Plate
4 Alternate Cover Plate Installation Detail

Provides minimum recommendations for the interior lining of existing steel and fiber-glass reinforced plastic (FRP) underground tanks and periodic inspection of steel underground tanks used for storage of petroleum-based motor fuels and middle distillates.