21 JANUARY 2003
Test frequently to verify that the atmosphere of the entire tank remains substantially free of
hydrocarbon and lead vapors.
11.15.4. When removing the interior tank coating, clean and grit-blast the walls to the bare metal. If
the coating has a high lead content, the method used for removal (burning, cutting, or grit blasting)
may result in a significant and additional hazard from lead vapor. Use an approved lead-vapor
respirator when working on inside surfaces. Before starting, verify the tank is free of hazards from
both petroleum and lead. The welder's facepiece, used with an SAR, protects against the hazards of
lead and lead fumes from coatings.
11.15.5. Vapor may enter through leaks in the tank bottom, or vapor pockets may exist in hollow
roof support columns or floating pan pontoons. Get advance approval from the MAJCOM fuels
engineer for hot work on any portion of POL facilities. This is required for both in-house or contract
11.15.6. Use only an API-certified welder when welding on POL facilities. Requirements are
outlined in API standards and ASME Boiler and Pressure Vessel Code, Section IX. At oversea
locations, certification may follow host nation standards and or requirements.
11.15.7. Obtain an AF Form 592, Welding, Cutting, and Brazing Permit, from the installation fire
department when workers perform hot work operations within a tank (see AFOSH Std 91-5). If
hazards may be introduced into the tank during hot work, contact the BEE to evaluate the potential
hazard and recommended ventilation procedures. See AFOSH Std 91-25, Paragraph 6.6, which
provides additional worker requirements.
11.15.8. Any area suspected of leaks (seams and new repair work) may be tested with a vacuum box.
The vacuum box is a rectangular frame (generally 0.3 meter [12 inches] wide by 0.7 meter
[30 inches] long by 152 millimeters [6 inches] deep) fitted with a glass top, and with a rubber seal
around the bottom edge. A manual or motor-driven pump is used to create a 50- to 101-millimeter
(2- to 4-inch) vacuum within the box. Soapsuds are placed over the area to be tested, and the vacuum
box is placed over the area with the rubber seal making an airtight contact between the tank surface
and the box. A vacuum is then developed within the box. If the vacuum box is moved over a leak,
the leak will be shown by activity in the soap bubbles over the leak.
11.15.9. The current interior tank coating system has a projected life of more than thirty years. In
most cases, failures should be minimal and touch-up painting, if any, is all that should be required. If
extensive failure is observed, advise your MAJCOM fuels engineer. Repair the coating using the
epoxy coating system in Navy Guide Specification Section 09973. Pay strict attention to surface
preparation since it is key to a successful job.
11.16. Returning to Service.
11.16.1. After the tank has been cleaned and all repairs have been made, the TES will re-enter and
inspect the tank.
11.16.2. After inspection, and before the tank is returned to service, conduct operational tests to
demonstrate functional capabilities. Reinstall all valves, piping, and manhole covers using new non-
asbestos gasket material compatible with the product being stored. Gasket thickness must not be less
than the thickness of the gasket replaced. Restore the entire area to its original condition. Do not fill
the tank faster than a fill-line velocity of 0.9 meter (3 feet) per second until the pan is floating freely
on the product and the fill lines in all other tanks are completely submerged under fuel.