Don’t throw away the plastic cap that comes with an isobutane canister and don’t lose it. When the valve rusts, it can start to leak gas or rust the inside of your cookpot when stored inside.
I had this happen to me after a backpacking trip. I was packing up my car to drive home and I heard a hissing sound, like gas escaping from a can. I pulled out my stove and saw that the valve on my gas canister was badly corroded. I’d misplaced the plastic cap that comes with the canister and suspect that the valve was damaged somehow or rusted open. I’m glad I caught it before closing up the trunk of my car because the leaking gas could have caused me to pass out on the highway or ignited. Boom.
How to Dispose of Rusted Isobutane Canisters
If you have old gas canisters in your house that aren’t empty yet, check to make sure that their valves haven’t rusted. If they have you might want to dispose of them, just to be on the safe side. Vent them by screwing on a canister stove and burning any remaining fuel, outdoors, to empty the canisters of flammable contents. When empty, puncture the cans and recycle them. This is more environmentally friendly than releasing the un-combusted gas and safer, so you don’t accidentally burn yourself by creating a spark when you puncture the can, using a screwdriver or the Jetboil Crunchit Tool, for instance.
Rusty Cook Pots
If you pack a gas canister in your cook pot, which is probably still wet after use, the plastic canister cap helps keep the canister valve dry and will prevent a rusting valve from staining your cook pot where it comes in contact with the metal. Eating rust is probably not good for you and it also takes some scrubbing to get rid of the rust.
Keep the Plastic Caps
Develop a habit of keeping track of the plastic cap when cooking in camp, so you don’t lose it. You might even consider carrying a spare in your gear repair kit if you have a habit of misplacing them. Most backpackers don’t use an entire canister over a 2-3 day weekend trip, so you’ll be able to use the canister for several trips if you protect the valve with the cap.SectionHiker is reader-supported. We only make money if you purchase a product through our affiliate links. Help us continue to test and write unsponsored and independent gear reviews, beginner FAQs, and free hiking guides.