GB8921-2011
Limit standards for 226Ra in phosphate fertilizer and its compound fertilizer
磷肥及其复合肥中226镭限量卫生标准
GB 8921-2011 is a current mandatory Chinese national standard for Limit standards for 226Ra in phosphate fertilizer and its compound fertilizer. It appears in the Food compliance cluster with a product safety focus and has an implementation date of May 1, 2012.
Applicability depends on product scope, certification route, competent authority notices and transition rules. Requst for the translation or verify source before using this record in a compliance decision.
Compliance overview
Scope and applicability
This standard applies to phosphate fertilizers and compound phosphorus fertilizers (collectively referred to as phosphorus-containing fertilizers) used in agriculture, including those for vegetables, fruit trees, and other edible crops. It does not apply to phosphate ore raw materials, as the ore requirements from the previous version (GB 8921-1988) have been removed. Manufacturers of any phosphorus-containing fertilizer intended for agricultural use in China must comply with this standard.
Technical requirements
The standard establishes a mandatory limit for the radionuclide 226Ra (Radium-226) content in phosphorus-containing fertilizers. The maximum permissible activity concentration is set at 500 Bq·kg⁻¹. This limit applies to all finished fertilizer products regardless of the source of phosphate ore used in production. Chapter 4, Section 5.1, and Chapter 6 are designated as mandatory provisions, while the remaining sections are recommended. Manufacturers must conduct annual sampling through their quality inspection departments, and additional sampling is required whenever production processes, raw materials, or material ratios are changed. The standard also defines result determination criteria: test results below 500 Bq·kg⁻¹ are deemed compliant. If initial results exceed this threshold, a re-sampling and retest must be conducted, and if the retest still exceeds 500 Bq·kg⁻¹, the product is judged non-compliant. Appendix A provides normative procedures for sample collection and preparation, including specific requirements for bagged and bulk-stacked fertilizers, minimum sample quantities, and drying/grinding protocols for test specimens.
Testing methods
The standard specifies two primary testing methods for 226Ra determination: (1) the scintillation emanation method (闪烁射气法) detailed in Appendix B, which involves alkali fusion, acid dissolution, radon accumulation, and alpha counting in a scintillation chamber; and (2) gamma spectrometry methods as referenced in GB 11713 (semiconductor gamma spectrometer for low-specific-activity samples) and GB 11743 (gamma spectrometry analysis of radionuclides in soil). The scintillation emanation method serves as the arbitration method for dispute resolution. Parallel test results must not differ by more than 20%.
FAQs
What products are regulated under GB 8921-2011?
GB 8921-2011 regulates all phosphate fertilizers and compound phosphorus fertilizers used in agriculture, including those applied to vegetables, fruit trees, and other edible crops. It covers finished fertilizer products but does not regulate phosphate ore raw materials.
Are there any updates from the previous version of GB 8921?
Yes, compared to GB 8921-1988, the 2011 version expands the scope from phosphate fertilizer only to include compound phosphorus fertilizers. It retains the same 226Ra limit of 500 Bq·kg⁻¹ but removes requirements for phosphate ore. It also adds gamma spectrometry as an alternative testing method and includes detailed sampling procedures in Appendix A.
What is the mandatory 226Ra limit and how is compliance determined?
The mandatory limit for 226Ra is 500 Bq·kg⁻¹. Test results below this value indicate compliance. If results exceed 500 Bq·kg⁻¹, a retest with newly collected samples is required. If the retest also exceeds the limit, the product is deemed non-compliant.
The summary above provides a high-level overview of GB 8921-2011. To ensure complete compliance for your fertilizer products entering the Chinese market, a precise and professional translation of the full technical specifications—including detailed sampling formulas, testing procedures, and calculation methods—is essential. Purchase our high-quality English translation of GB 8921-2011 today to access all detailed parameters, tables, appendices, and testing procedures.
Applicability hints
- Type
- Health and hygiene
- CCS
- C57
- ICS
- 13.280
- Competent department
- National Health Commission
- Technical committee
- National Health Commission
Relationships
Replaces:GB 8921-1988