Waste liquefied gas cylinders should be sent to the gas company's testing station for testing. If they are overdue or excessively corroded, the inspection station will destructively treat them and then return them to the owner.
Steel cans that are eliminated in batches every year are reused as garbage bins or stoves. There are potential safety hazards in the gas storage tank, and the company generally cannot determine whether the gas storage tank is scrapped or not, so it must pass the test.