Key takeaways
- Type A and Type B bags are for non-flammable surroundings only.
- Type C bags must be earthed every time they are filled or emptied.
- Type D bags dissipate static safely without earthing.
- If you are unsure, send us your product's safety data sheet and we will recommend a type.
Filling or emptying a jumbo bag creates static electricity. Fine powders sliding against woven fabric can build up a charge large enough to spark. If flammable dust, gas or solvent vapour is present, that spark can start a fire or explosion.
The four FIBC types, defined in IEC 61340-4-4, describe how each bag deals with that charge.
The four types at a glance
| Type | How it works | Earthing | Use with flammable materials |
|---|---|---|---|
| Type A | Plain woven polypropylene — no static protection | Not applicable | No |
| Type B | Low breakdown-voltage fabric that prevents the most energetic discharges | Not applicable | Not where flammable vapour or gas is present |
| Type C | Conductive threads woven into the fabric carry the charge away | Required — always earth the bag | Yes, when earthed |
| Type D | Static-dissipative fabric releases charge safely into the air | Not required | Yes |
Type A: for safe, non-flammable products
Type A bags are the simplest and lowest-cost option. They are fine for non-flammable products such as sand, cement or fertilizer in areas with no flammable atmosphere.
Type B: a step up, still not for flammable surroundings
Type B fabric stops the high-energy "propagating brush" discharges that plain bags can produce. It does not stop all sparks, so Type B bags should not be used where flammable vapour or gas is present.
Type C: conductive, and must be earthed
Type C conductive bags have conductive threads woven through the fabric and an earth tab. Connected to earth during filling and discharge, they carry the static charge safely away. The risk is human: if an operator forgets to connect the earth clip, the bag offers no protection.
Type D: protection without earthing
Type D antistatic bags use a static-dissipative fabric that releases charge into the air in small, safe amounts. No earthing is needed, which removes the risk of a forgotten clip.
How to choose
- Is the product or the surrounding area flammable? If not, Type A or B is usually enough.
- Can you guarantee earthing every single time? If yes, Type C is a proven option.
- If earthing can't be guaranteed, choose Type D.
Every site is different. Send us your product's safety data sheet and filling set-up, and our team will recommend the right type.
Frequently asked questions
Can I use a Type C bag without earthing it?
No. An unearthed Type C bag can build up a dangerous charge. If you cannot guarantee earthing every time, choose a Type D bag.
Which standard defines FIBC Types A to D?
IEC 61340-4-4 sets the electrostatic requirements and test methods for FIBC Types A, B, C and D.
Does Blue Line Pack make Type C and Type D bags?
Yes. Both are made to order in our factories in Abu Dhabi, UAE and Salalah, Oman.