GB 4806.9 vs EC 1935/2004: Food-Contact Stainless Steel Rules

Two Regulatory Routes to the Same Goal

Food-contact stainless steel sold into China and into the European Union is governed by two systems that look similar on a specification sheet but operate very differently in law and in practice. GB 4806.9 is China's national food safety standard for metal materials and articles in contact with food: a single, mandatory standard that fixes permitted alloy compositions, migration limits and the test methods used to demonstrate compliance. EC 1935/2004 is the European framework regulation on materials and articles intended to come into contact with food: it sets the general safety obligation and the system of documentation, while detailed limits for metals come from national provisions and harmonised guidance rather than from one consolidated EU text. For a supplier shipping the same 304 or 316L vessel to both markets, the practical consequence is that one set of alloy and migration data can serve both, but two different compliance dossiers are required.

Scope and Legal Character Compared

Item	GB 4806.9	EC 1935/2004
Legal character	Mandatory national food safety standard issued under China's Food Safety Law	EU framework regulation directly applicable in all member states
Scope	Metal materials and articles contacting food, including stainless steel, aluminium, tinplate and coatings	All food-contact materials and articles, including metals, plastics, paper and ceramics
How limits are set	Composition requirements, migration limits and test methods consolidated in the standard itself	General safety obligation in Article 3; specific limits via specific measures, national rules and metals guidance
Core documents	Compliance test report, specification and batch records	Declaration of compliance, supporting test data, traceability records
Market role	Condition for lawful sale of metal food-contact articles in China	Condition for lawful placing on the EU market of any food-contact material

The structural difference matters when a buyer asks a mill for "the certificate". Under GB 4806.9 the deliverable is normally a test report against the standard's own clauses. Under EC 1935/2004 the deliverable is a declaration of compliance backed by test data and by evidence of good manufacturing practice, usually through a quality system audited to the framework's manufacturing requirements.

Alloy Composition and Acceptable Grades

Both systems restrict which alloys may be used rather than accepting any corrosion-resistant steel. In practice the commercial grades that satisfy both are the austenitic 304 and 316L families, the low-carbon and stabilised variants used for welded vessels, and the ferritic 430 family for dry-contact applications such as cutlery holders and appliance panels. Two composition points drive acceptance:

Carbon content must be low enough to avoid sensitisation at weld heat-affected zones, which is why 316L and its stabilised equivalents are preferred for welded food equipment.

Alloying additions that improve corrosion resistance must not introduce elements restricted by the compositions permitted in the standard, and any coating or surface treatment must also be covered.

Recycled or re-melted feedstock must be traceable to a heat number so that the composition of the finished article can be demonstrated from mill records.

Electropolished and passivated finishes are widely used to meet the surface requirements that accompany these composition rules, since a smooth, chromium-rich passive layer reduces both product adhesion and metal release into the food.

Migration Limits, Simulants and Testing

This is the area where the two systems are most often misreported. The Chinese standard applies a general heavy-metal migration limit expressed as lead, commonly cited as 0.05 mg/kg, alongside element-specific limits for cadmium at 0.005 mg/kg and other restricted elements. Those two figures belong to different categories of limit, and comparing the general limit against a cadmium-specific limit, as some secondary articles do when they claim one system is a fixed multiple stricter than the other, produces a meaningless ratio.

Test point	GB 4806.9	EC 1935/2004 route
General heavy metal migration (as Pb)	≤ 0.05 mg/kg	Not fixed at framework level
Cadmium migration	0.005 mg/kg	0.005 mg/kg under the metals guidance applied in national measures
Simulant basis	Acetic acid solution per the GB 31604 test series	Food simulants selected to match the food type in national provisions
Exposure conditions	Standardised time and temperature cycles for repeated-use articles	Worst-case foreseeable use, with migration testing repeated as required
Who runs the test	Accredited laboratory against the Chinese standard	Accredited laboratory against the applicable method accepted by the member state

For welded process equipment, migration testing must be carried out on the finished article or on a representative sample that includes a weld, because the weld and its heat-affected zone release more metal than the parent plate. Sensitised material, heavy cold work and rough as-welded surfaces all raise measured release, so a test certificate from a smooth mill-finish coupon may not represent the delivered vessel.

Documentation, Traceability and Factory Controls

Compliance fails more often on paperwork than on metallurgy. A workable dossier for both markets contains the following:

Mill test certificates with heat numbers tied to the finished article, showing composition within the current standard edition.

Migration test reports from an accredited laboratory, referencing the simulant and the exposure conditions actually used.

A declaration of compliance for the EU market covering the substance groups tested and the restrictions applied.

Manufacturing records demonstrating hygiene controls, cleaning between grades and control of surface treatment chemicals.

An internal procedure for following standard revisions, since both systems are updated periodically and an outdated test report can invalidate a batch.

Because GB 4806.9 is a national standard while EC 1935/2004 depends on national measures in each member state, suppliers shipping to several EU countries should confirm the specific requirements of the destination country in addition to the framework obligations, then align the two dossiers so the same test data can be reused.

FAQ: GB 4806.9 and EC 1935/2004 in Practice

Q: What is the main difference between the two rules?
GB 4806.9 is a single mandatory Chinese standard containing composition, migration and test requirements; EC 1935/2004 is an EU framework regulation that sets general safety and documentation duties, with metal limits coming from national measures and guidance.

Q: Which stainless grades satisfy both systems?
304, 316L and their low-carbon or stabilised variants for welded food equipment, and 430-type ferritic grades for dry-contact parts, provided composition and migration testing are documented.

Q: Is the EU cadmium limit really a fixed multiple stricter than the Chinese rule?
No. The 0.05 mg/kg Chinese figure is a general heavy-metal limit expressed as lead, while 0.005 mg/kg is an element-specific cadmium limit, so the two must not be divided into a ratio.

Q: Can a mill certificate alone prove compliance?
No. The mill certificate proves composition only; migration testing on a sample including a weld, plus the appropriate declaration, is required for the finished article.

Q: Does surface finish affect migration results?
Yes. Rough as-welded and sensitised surfaces release more metal, so electropolished or well-passivated surfaces give lower measured values and are preferred for hygiene-critical equipment.

Q: How should a supplier handle standard revisions?
Keep a procedure that tracks the current edition of GB 4806.9 and of the relevant national measures in each EU destination, and retest when composition, finish or welding procedure changes.