ISO 21898: All About Big Bag Certification
ISO 21898:2004 is an international standard specifying requirements for the design, manufacture, testing, and labeling of Flexible Intermediate Bulk Containers (FIBCs). The full title of the document is: 'Packaging — Flexible intermediate bulk containers (FIBCs) for non-dangerous goods'. It is published by the International Organization for Standardization (ISO); in August 2024 the new edition ISO 21898:2024 replaced the 2004 edition.
If you purchase big bags for your enterprise, understanding ISO 21898 will help you distinguish a high-quality container from a potentially dangerous one. The standard applies to big bags for non-dangerous goods. Packaging for dangerous goods follows separate UN rules, while for combustible powders and explosive atmospheres FIBCs are classified as types A, B, C and D by their electrostatic properties (IEC 61340-4-4).
Main requirements of the ISO 21898 standard
The standard covers the entire lifecycle of a big bag — from the fabric material to the label on the finished product. Key sections:
Materials
Requirements for polypropylene fabric: tensile strength and UV resistance.
Construction
Requirements for seams, lifting loops and their attachment to the body, the bottom and the top.
Testing
Type tests: top lift, cyclic top lift (for multi-trip bags), stacking, drop, topple, righting and tear resistance.
Labeling
Mandatory information on the label: manufacturer's name, SWL, safety factor, production date, material, tare weight, handling recommendations.
Safety Factor (SF): 5:1 and 6:1
This is the most critical parameter of a big bag from a safety perspective. The Safety Factor (SF) indicates how many times the destructive load exceeds the nominal one (SWL — Safe Working Load).
SF 5:1 — single trip
A big bag with a SWL of 1000 kg and SF 5:1 will withstand a load of 5000 kg during destructive testing. Designed for one transport cycle. After unloading, the container is disposed of.
SF 6:1 — multiple trip
A big bag with a SWL of 1000 kg and SF 6:1 will withstand 6000 kg during destructive testing. Designed for 2–3 full transport cycles. An additional requirement is a cyclic top lift test.
SWL (Safe Working Load) is the figure you see on the label. For example, 'SWL: 1000 kg, SF: 5:1' means: nominal load capacity is 1000 kg, the container will break at a load of ~5000 kg. The 400% margin is protection against dynamic loads during crane lifting, swaying, and uneven weight distribution.
What happens if overloaded? A big bag will not burst immediately if the SWL is exceeded by 10–20%. However, regular overloading accelerates the degradation of the fabric and loops, especially under UV radiation and temperature fluctuations. The consequence is an unpredictable tear during the next lift. Therefore, exceeding the SWL is strongly discouraged.
Types of standard tests
ISO 21898 defines type tests that a big bag design passes before mass production. The test conditions (loads, heights, number of cycles) are set out in the annexes of the standard:
| Test | What it checks |
|---|---|
| Top lift | Strength of the loops, their attachment and the body under a load that is a multiple of the SWL set by the safety factor |
| Cyclic top lift (SF 6:1 only) | Whether the bag withstands many lifting cycles in a row — proof of multi-trip use |
| Drop | Integrity of a filled bag after a drop onto a hard surface |
| Topple | Whether a filled bag stays intact when it topples onto its side |
| Righting | Whether the loops can lift a bag lying on its side back to upright |
| Tear | Whether a cut in the fabric spreads under load |
| Stacking | Ability to carry the weight of other filled bags on top |
Labeling requirements for big bags
Every big bag complying with ISO 21898 must have a label or printed marking with the following information:
- ✔Manufacturer's name and address
- ✔SWL (Safe Working Load) in kilograms
- ✔Safety Factor: 5:1 or 6:1
- ✔Material of the container body and loops
- ✔Production date (month and year)
- ✔Empty container mass (tare)
- ✔Marking 'for single-trip' or 'for multiple-trip' use
- ✔Instructions for safe lifting and stacking
Practical tip: upon receiving a batch of big bags, check for the presence of all items on the label. The absence of SWL marking or safety factor is a sign of uncertified production. Such containers create a risk of accidents and can be grounds for an insurance company's refusal to pay.
Why certification matters to the buyer
A big bag weighing 1–2 tons lifted by a crane to a height of several meters is a potentially hazardous object. A container tearing during a lift threatens:
- ✔Injuries to workers at the facility or warehouse
- ✔Loss of cargo worth significant amounts
- ✔Territory contamination (especially for chemicals)
- ✔Legal liability for workplace accidents
- ✔Refusal by the insurance company to cover losses (if the packaging is not certified)
For export shipments, packaging requirements are set by the contract with the buyer; ISO 21898 compliance is the most common way to show that the bag design has passed the type tests.
Frequently Asked Questions
Looking for a reliable supplier? UkrBagPak is a Ukrainian manufacturer since 2014. Buy big bags wholesale from the manufacturer directly, without intermediaries. Over 150 product items of flexible packaging, including 2- and 4-loop big bags with valves and liners, from 500 to 3000 kg. ISO 21898 certified, 1-day shipping across Ukraine.
What does 5:1 and 6:1 mean on a big bag label?
This is the Safety Factor. 5:1 means the container withstands a load 5 times greater than the nominal one — for single-trip use. 6:1 — 6 times greater — for multiple trips (2–3 cycles).
Is ISO 21898 certification mandatory in Ukraine?
Legally — no, ISO 21898 is not mandatory in Ukraine. However, it is an industry standard adhered to by all serious manufacturers. Large buyers (agricultural holdings, chemical plants, exporters) require ISO compliance as a purchasing condition.
How to check if a big bag complies with ISO 21898?
Check the label: SWL, safety factor, manufacturer, and production date must be indicated. Ask the supplier for a test report and a certificate of conformity. Reliable manufacturers provide these documents upon request.
Which edition of ISO 21898 is current?
ISO 21898:2024 — published in August 2024, it replaced the 2004 edition. The edition a bag was tested to is stated in the supplier documents.
If you need official compliance documentation, order ISO 21898 certified FIBC containers directly from the manufacturer, not from a reseller. UkrBagPak products comply with ISO 21898:2004, and every big bag passes a quality check before shipping.