Method for washing gas supply part in gas inspection apparatus

A method for cleaning a gas supply unit of a gas inspection apparatus, the gas supply unit comprising a plurality of supply paths and a plurality of supply ports, wherein each supply path is configured to channel gas from a corresponding supply port of the plurality of supply ports to an inspection unit, the method comprising steps of:

• connecting a plurality of sample-gas bag containers to the plurality of supply ports such that each sample-gas container of the plurality of sample-gas bag containers is connected to a corresponding supply port of the plurality of supply ports, wherein each sample-gas bag container contains its own sample gas sealed therein such that a plurality of sample gases is contained in the plurality of sample-gas bag containers;
• supplying each sample gas sealed in the sample-gas bag containers sequentially from the plurality of supply ports to the inspection unit, to perform a gas inspection;
• after the gas inspection is performed, replacing the plurality of sample-gas bag containers with a plurality of cleaning-gas bag containers in which a cleaning gas is sealed such that each cleaning-gas container of the plurality of cleaning-gas bag containers is connected to a corresponding supply port of the plurality of supply ports, wherein the cleaning gas is different from each of the plurality of sample gases;
• and
• suctioning the cleaning gas sequentially from each of the plurality of supply ports and depressurizing each supply path such that each supply path is cleaned by the cleaning gas and depressurization.