Study on the influence of 0.1 mg sensitivity mass comparator on the uncertainty of reference gas prepared by gravimetric method

The uncertainty source during the gravimetric procedure caused by the application of 0.1 mg sensitivity mass comparator is discussed and evaluated according to standard procedure. The uncertainty of one single weighing procedure is 0.2 mg by using 0.1 mg sensitivity mass comparator. By enlarge the filling amount of the component, the former main contribution (uncertainty of weighing) of the obtained reference gas become lower than other uncertainty sources such as the uncertainty of purity, even the uncertainty of mass molecular. The standard uncertainty of reference gas could be less than 0.02% while the reference gas is prepared by 0.1 mg sensitivity mass comparator.