Definitions of electrostatic FIBCs
Concerning the aspects of the avoidance of electrostatic-ignition hazards, up to now four types of FIBCs (A, B, C and D) are in use according to their ability of charge dissipation and/or limiting the energy of possible discharges.
These four types of FIBCs are explained below:
FIBCs made from non-conductive materials without any measures against electrostatic charging.
As no electrical conductive material is interwoven in the fabric grounding and charge dissipation is hardly possible. Explosive atmospheres of gases as well as explosive atmospheres of dusts can be ignited. Therefore, a Type A FIBC must not be used to handle combustible dusts.
Safe way of usage: Used for the transportation of non flammable or non explosive goods. There should be no flammable or explosive solvent or gas in the environment.
Never Use: For the transportation of flammable or explosive goods. If there exists any flammable or explosive gas in the environment.
Safe handling in potentially explosive environments
Some FIBC applications occur in potentially hazardous explosive atmospheres. Filling and Discharging creates static electricity. Fine powders with low (MIE) minimum ignition levels can create combustible dust clouds within the bag and surrounding environment.
Need for FIBC grounding & special handling equipment
Compliance with EC 10/2011 & FDA food contact regulation
Possibility to control the FIBC with metal detection
Dissipation of static charge via Unique built in characteristics
Are electrostatic charges dangerous?
Electrostatic charges are not dangerous by themselves but they may be dangerous when there is a risk of gas discharge.
Different types of gas discharges are as follows
Generally, there are two situations that bear danger:
1-Explosive Materials – When explosive materials are filled into big bags the usage of conductive big bags is determined by the minimum ignition energy of the materials.
2-Explosive Environment – An explosive environment can be given by dust, gases or steam. The highest danger is given when the explosive environment consists of gases or steam.
MIE of dust
Dust zones 21-22 (1000 mJ MIE > 3 mJ)
Gas zones 1-2 (Groups IIA/IIB) or Dust zones 21-22 (MIE < 3 mJ)
MIE > 1000 mJ
A, B, C, D
B, C, D
1000 mJ > MIE > 3 mJ
B, C, D
B, C, D
MIE < 1000 mJ
Type C FIBC labels
- Labels greater than 100 cm² in area shall not be made from material with surface resistivity greater than 1,0 × 10^12 Ω.
- Labels made from materials with surface resistivity less than 1,0 × 10^7 Ω can be used, provided the resistance to groundable point is less than 1,0 × 10^7 Ω.
- Labels made from materials with surface resistivity between 1,0 × 10^9 Ω and 1,0 × 10^12 Ω can be used.