Table 5.

Typical calibration values for a set of fractional weights.The uncertainties are given at a level of 1 standard deviation accord-ing to [31]. The uncertainty is virtually all statistical in nature(Type A). The results are correlated so that, for example, the uncer-tainty in the combination of (50 mg + 30 mg+10 mg) is 0.27 μg.

Nominal Mass (mg)	Correction (mg)	Uncertainty (μg)	Vol. at 20 °C (cm3)	Coef. of Exp. (10−6/°C)
50	−0.02936	0.23	0.00301	20
30	−0.01361	0.19	0.00181	20
20	−0.02715	0.15	0.00740	69
10	−0.02037	0.18	0.00370	69
5	−0.01514	0.15	0.00185	69
3	−0.02223	0.16	0.00110	69
2	+0.00971	0.14	0.00074	69
1	+0.03106	0.18	0.00038	69