Reference Clauses of the Act : Arts. 24-2 through 24-5
It means changing the state of high pressure gas instantly to a non-high pressure gas for a certain purpose other than disposal by combustion, reaction, dissolution or other means with decompression equipment, which is a single device such as a reducing valve, and using the non-high pressure gas produced from that change. The following two cases can be contemplated:
(i) changing a high pressure gas to a non-high pressure gas of the same variety (decompression); and
(ii) changing a high pressure gas to a substance (including high pressure gas) of a different variety. (production of a new variety of gas by reaction, and combustion and dissolution fall into this category; vaporized liquefied gas is not deemed as a different variety.)
In actual handling, in the case set forth in item (ii) above, if the process also falls under the category of production of high pressure gas (e.g. a case where high pressure nitrogen gas is reacted with high pressure hydrogen gas to turn into high pressure ammonia gas), in many cases, the process is not considered consumption of nitrogen and hydrogen only when it is included in a series of processes.
Moreover, in the case of a consumer of Specific High Pressure Gas, the consumer needs to submit a notification report to the district prefectural governor, and consumers other than the above consumer (a person who consumes flammable gas (including liquefied petroleum gas), toxic gas, oxygen, or air) shall consume those gases in accordance with the criteria set by the regulations.