Electrostatic FIBC Classification for Type C

Type C bulk bags are those designed with grounding in mind, and with an ultimate goal of preventing and minimizing electrostatic hazards. They can be used in almost all hazardous areas and must be grounded, so it is often a best practice to treat them as a metal drum.

The standard requires that these bags be built entirely from conductive materials, or at the very least, they must contain a system of fully interconnected conductive threads or tapes. If the threads or tapes are in a stripe pattern, they must be closer than 20mm apart. The gap can extend as far as 50mm if they are placed in a grid pattern.

A few other elements of the electrostatic FIBC classification for Type C bags include:

• Requires a material resistance to groundable point of <1.0×107 Ohm.
• It must present resistance from any location on the FIBC to the groundable point of <1.0×107 Ohm.
• Are approved for use even in the presence of flammable vapors and gases.
• If using when combustible dusts are present, they must have an MIE ≤3mJ.
• For use such as filling and emptying, the bag must be electrically grounded.
• Bags constructed of multilayer materials will need to have at least the inside or outside surface of the FBIC presenting a resistance to ground of less than 107 Ohm.
• For multilayer-constructed bags whose inside layer doesn’t meet the 107 Ohm resistance requirement, the material needs to have a breakdown voltage of ≤6kV.
• Materials used to craft inner baffles that are not mesh, or net baffle designs, must meet all of the other Type C requirements.

It’s important to remember that Type C bags, when left isolated from the ground, may pose greater ignition risks than Type A or Type B FIBCs.

Type C

Used safely to transport flammable powders

Used safely when flammable solvents or gases are present around the bag

DO NOT USE when ground connection is not present or has become damaged