This standard stipulates that the obtained raw granular fertilizer samples shall be prepared into laboratory samples for analysis by operations such as fractionation and grinding. This standard is only applicable to compound fertilizers made by chemical methods or compound fertilizers made from nitrogen, phosphate, and potassium fertilizers through secondary processing.
GB/T 8571-2002 history
2008GB/T 8571-2008 Preparation of laboratory samples for compound fertilizers