Plateau Value on a Gas Flow Counter

Identify all the controls on the instrument using the instruction manual as a guide. 

Turn on the instrument and allow it to warm up for 20-30 minutes. Permit the sample chamber to purge with the counting gas mixture during this time. 

Count a standard sample for 1 minute and then increase the voltage by 50 V. 

Continue the procedure until the counts begin to again increase and stop. Further voltage increases will result in continuous discharge and damage to the chamber. 

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