在美国药典USP37-NF32 第二增补本的凡例(General Notice)中“6. TESTING PRACTICES AND  PROCEDURES”项下有如下规定：

6.40.10. Ignite to Constant Weight
"Ignite to constant weight” means that ignition shall be continued at 800 ± 25, unless otherwise indicated, until two consecutive weighings, the second of which is taken after an additional period appropriate to the nature and quantity of the residue, do not differ by more than 0.50 mg per g of substance taken.

6.40.10 炽灼至恒重

“ 炽灼至恒重”是指除非另有说明，否则应以800±25的温度继续炽灼 ，直到两次连续称量，第二次称量是在根据残留物的性质和数量的额外时间之后进行的，相差不超过 每克摄入的物质超过0.50毫克。

6.40.20. Dried to Constant Weight
"Dried to constant weight” means that drying shall be continued until two consecutive weighings, the second of which is taken after an additional drying period appropriate to the nature and quantity of the residue, do not differ by more than 0.50 mg per g of substance taken.

6.40.20 干燥至恒重
“干燥至恒重”是指干燥应持续至两次连续称重，第二次称重是在根据残留物的性质和数量进行的额外干燥时间之后进行的，每克物质的差异不得超过0.50 mg 采取。