How EU Chemical Buyers Audit an FIBC Factory and Verify UN Reports
Published 6 November 2026 · BULKFORTE
EU chemical buyers audit an FIBC factory by checking the floor, incoming fabric and loops, and the UN dangerous-goods report against the bag on the order. A UN test report covers only the bag specification that was tested. An on-site audit of a contracted partner factory can be arranged before you order.
On this page
What an audit is checking
A test report and a factory audit answer different questions. The report shows how one bag design behaved in a laboratory. The audit shows whether the plant that will sew your order can repeat that design: the fabric it receives, the loops it sews in, and the records that tie a finished bale back to the spec.
Chemical buyers usually care about three things at once. The product must stay in the bag. If the product is dangerous goods, the bag on the order must be the bag the UN code describes. And the plant must be one you are allowed to walk. A UN test report covers only the bag specification that was tested.
Factory audit checklist
Use this as a walk-through, not as a scored certificate. Agree the spec in writing before the visit, and compare what you see with that spec. We do not publish stitch counts, fabric weights or audit scores here.
| Area | What to compare with the order |
|---|---|
| Who you are buying from | The company on the purchase order, and the facility where the bags are actually cut and sewn |
| Incoming fabric | Weight, width, coating and any UV mark, against the agreed spec |
| Webbing and loops | Width, colour, and how each loop is sewn into the body |
| Seams and spouts | Seam type, fill spout, discharge spout and document pouch |
| Liner | Present or absent, and the same construction the UN code names |
| Identity | A batch or order mark that ties the finished bags to the tested specification |
| Records | In-process checks, and a record of finished-bag samples |
| Loading | How bags are baled, and how a container is loaded |
Our own QC team inspects the order before loading. Shipment photos and video are available on request. For a lot check after production, see how to inspect bulk bags before shipment.
What UN 13H3 and 13H4 mean
Flexible IBCs for dangerous goods are marked with a UN code. For woven plastic the codes in common use on bulk bags are:
- 13H1 — uncoated fabric, no liner.
- 13H2 — coated fabric, no liner.
- 13H3 — uncoated fabric, with a liner.
- 13H4 — coated fabric, with a liner.
13H3 and 13H4 both include a liner. The difference is the outer fabric: 13H3 is uncoated, 13H4 is coated. Coating closes the weave; the liner is a separate film bag inside. Chemical powders that must not sift are often written as 13H4, but the code is decided by the dangerous-goods classification and the packing instruction, not by a catalogue default.
A UN test report covers only the bag specification that was tested. The code on the bag, the code on the report and the construction on the order need to be read together. A 13H3 approval and a 13H4 approval are not interchangeable. For a different size, fabric or other detail, check the report, the approval and the variations it permits. A change outside that scope is assessed by the laboratory or the competent authority.
Packing group letters and the order of the mark
On an IBC the mark follows a fixed order in the UN Model Regulations, 6.5.2.1.1. After the UN symbol and the design code (such as 13H3 or 13H4), the next character is a packing-group letter:
- X — the design type is approved for packing groups I, II and III. For IBCs, X applies to solids.
- Y — packing groups II and III.
- Z — packing group III only.
The mark then continues, in this order: the month and year of manufacture, the country that authorised the mark, the manufacturer identification, the stacking test load in kilograms, and the maximum permissible gross mass in kilograms. Read those from the mark and the report. The letter and the figures on a given order are Available on request. An X does not replace a check that the code matches the bag.
The tests themselves — top lift, stacking, drop, topple, tear and righting — are set out in the UN Model Regulations, chapter 6.5 (UNECE). A buyer's checklist for reading the report is in how to verify an FIBC test report.
How to verify a UN report is authentic
Do this before you treat the PDF as evidence for your order:
- Read the laboratory's name, the accreditation body and the registration number on the report.
- Look that laboratory up in the accreditation body's public directory. For a CNAS-accredited lab, start with the CNAS directory and confirm the relevant test is inside the lab's scope. The directory confirms the lab, not the individual report.
- Ask the laboratory to confirm the report number, the date and the applicant. Take the email address from the laboratory's own website, never from the file you were sent.
- Put the report next to your purchase order. Dimensions, fabric, coating, liner, loops and the UN code should describe the bag you are buying.
- Check the test date, and ask whether the design has changed since the sample was tested.
A UN test report covers only the bag specification that was tested. We do not publish report numbers on this site. If a supplier says every bag they make carries the same UN approval, ask which specification was tested.
Arranging a factory audit
We supply FIBCs through contracted manufacturing partners in China. Production, inspection and loading take place at their facilities, and buyers are welcome to audit any factory on site.
Tell us the bag, the port and who from your side will attend. We agree the facility and the date. The date and any visit cost are Available on request. You can visit before you order, or while your bags are in production.
Our partner factory has passed SGS factory audits and holds UN dangerous-goods FIBC test reports (Zhengzhou Customs, CNAS-accredited). Copies available on request; other third-party tests (e.g. ISO 21898 top-lift) can be arranged through accredited labs.
A UN test report covers only the bag specification that was tested. Name any accredited laboratory and the test you need, and we arrange it. SGS, BV and Intertek are examples, not a fixed list. We reply within 12 hours (GMT+8).
The bags this applies to are on the UN bag and Type A–D section of the bulk bags page, and the chemical models are under chemicals. To start, send an inquiry or read how we work.
FAQ
What should an FIBC factory audit cover for chemical cargo?
The floor where the bags are sewn, incoming fabric and webbing against the agreed spec, seam and loop construction, liner fitting when the bag is a UN 13H3 or 13H4, a mark that ties the lot to the tested spec, QC records, and how the bags are loaded. An audit does not replace a UN test report. A UN test report covers only the bag specification that was tested.
What is the difference between UN 13H3 and 13H4?
Both are woven-plastic flexible IBCs with a liner. 13H3 is uncoated fabric with a liner. 13H4 is coated fabric with a liner. 13H1 is uncoated without a liner and 13H2 is coated without a liner. The code on the bag, the code on the report and the bag on the order have to match. A UN test report covers only the bag specification that was tested.
How do I check that a UN test report is genuine?
Read the laboratory name and its accreditation, look the lab up in that body's public directory, then ask the lab — using contact details from its own website, not from the PDF — to confirm the report number. Then match every construction line to your order. A UN test report covers only the bag specification that was tested.
Does one UN report cover every bag a factory makes?
No. A UN test report covers only the bag specification that was tested. A different size, fabric weight, coating, liner or loop design needs its own assessment. A sentence that says every bag is UN-certified is a reason to stop and ask which specification was tested.
Can I visit the factory that will make my order?
We supply FIBCs through contracted manufacturing partners in China. Production, inspection and loading take place at their facilities, and buyers are welcome to audit any factory on site. Tell us the order and who will attend. The date and any visit cost are Available on request.
Can I see the UN report before I travel?
Our partner factory has passed SGS factory audits and holds UN dangerous-goods FIBC test reports (Zhengzhou Customs, CNAS-accredited). Copies available on request; other third-party tests (e.g. ISO 21898 top-lift) can be arranged through accredited labs. A UN test report covers only the bag specification that was tested. We send copies to the buyer on request. We do not publish the reports, or any report number, on this website. Request the report and an audit date.