The flow rate prescribed by your veterinarian will determine how long the Canister lasts.
Pawprint Oxygen Canisters can last up to 20 minutes. How long the Canister lasts is dependent on the flow rate prescribed by your veterinarian. The flow rate is the "dosage" of the oxygen drug and determines the rate at which the oxygen gas leaves the Canister.
The Regulator is a part of the Pawprint Oxygen Canister system and is what dictates the flow rate. Pawprint Oxygen will provide you with a Regulator that is pre-set to the flow rate prescribed by your veterinarian.
These are the durations that the Canister will last for each of the flow rates:
0.5 Liters per minute: 20 minutes
1.0 Liters per minute: 10 minutes
2.0 Liters per minute: 5 minutes
The attending veterinarian is responsible for determining the appropriate flow rate. Flow rate determination are typically based off pet weight and condition.