A.2 Characteristics and uncertainties of the composition of the gas mixtures
A.2.1
The volume fraction for the components to be determined in N in cylinders or in a gas mixture obtained from the generator shall be given in parts per million (ppm) (see 4.1).
A.2.2
The blend tolerances of the calibration gas mixtures shall not exceed 10 % of the volume fraction of each component.
A.2.3
For calibration gas mixtures the uncertainty in the composition shall be 2 % or less of the certified (assigned) value of the volume fraction for the components to be determined. The composition of other gas mixture components shall have an uncertainty of no more than 3 %.