USP41
“Measurement uncertainty is satisfactory if three times the standard deviation of not less than ten replicate weighings divided by the amount weighed, does not exceed 0.001 (0.1 %).”
基本上可读性为0.1mg的天平,理论上符合USP的最小称量值也在100mg以上,可读性0.01mg的理论值至少也是约在10mg以上