Patent ID: 8239171

Claim:
A method for impurities measurement in noble gases, comprising steps of: a) providing a gas sample having at least one interfering impurity and at least one impurity to be measured therein, wherein at least one impurity to be measured is an impurity other than H 2 O; b) providing at least one trapping means to define an impurities trap having an inlet and an outlet, said at least one trapping means being adapted to trap at least one interfering impurity without affecting the at least one impurity to be measured; c) introducing the gas sample at the inlet of the impurities trap for removing said at least one interfering impurity; d) reducing the effect of variations in moisture content within the gas sample on measurement of a first impurity to be measured, wherein said first impurity is an impurity other than H 2 O, by adding moisture to the gas sample; e) introducing the moisturized gas sample obtained in step (d) in a plasma cell of a plasma emission system; f) collecting an emission light generated by the plasma cell at a specific emission wavelength not subjected to spectral interference for providing an emission signal representative of a concentration within the sample gas of at least said first impurity to be measured; and g) measuring the concentration of at least said first impurity to be measured according to the emission signal provided in step (f).