EHS provides the waste collection service. To manage the used canisters while awaiting pickup, label the canisters as waste and store them in a sealed plastic bag or box to avoid off-gassing into the room.
Then fill out a Chemical Waste Pickup Request form. EHS will collect the canisters from your lab and dispose of them properly. There is no charge for the service.
Contact Jim Pyrz at firstname.lastname@example.org or 5-4625 if you have questions or need assistance.