Exploding Fuel Canisters: Understanding the Risks and Ensuring Safety on the Trail

Published August 21, 2026 04:05AM

The evolution of backpacking stoves has seen a significant shift from traditional liquid-fuel models to the more prevalent canister-based systems. While liquid-fuel stoves retain their utility in extremely remote locations where kerosene might be the only accessible fuel source, the modern canister stove has largely supplanted them due to its inherent advantages. Today’s canister stoves are lauded for their reduced weight, enhanced reliability, and improved performance, even in challenging winter conditions, when managed judiciously. However, a critical drawback persists: the potential for fuel canisters to explode. Though infrequent, these incidents can have severe consequences, as canisters contain highly flammable gas under pressure. Mishandling or exposure to extreme conditions can lead to a catastrophic combustion event.

To comprehensively address the risks associated with fuel canisters, Backpacker’s Editor-in-Chief, Adam Roy, and Outside’s Lab Test Editor, Adam Trenkamp, ventured to the Outside Lab at CU Denver. Their investigation delved into the critical aspects of canister safety, the potential destructive power of an exploding fuel canister, particularly within a vehicle, and the essential knowledge backpackers need to utilize their stoves without incident.

The conversation commenced with a direct question from Trenkamp: "Can I get it warm enough to make it explode?" This set the stage for Roy’s more direct framing of the issue: "I’m Adam Roy, Editor-In-Chief of Backpacker, and this is my colleague Adam Trenkamp, Outside’s Lab Test Editor. We are here at the Outside Lab at CU Denver. Adam, do you know what the quickest way to ruin a backpacking trip is?" Trenkamp’s lighthearted guess of "Eating lettuce?" was met with Roy’s stark response: "Blowing your fingers off."

Roy elaborated on the fundamental nature of canister stoves as a revolutionary advancement in backpacking technology, simplifying cooking and reducing overall pack weight. However, he highlighted the often-overlooked inherent danger: "we’re all walking around with a small explosive in our backpacks at all times. And that isn’t really a danger most of the time, but under some circumstances, this can be, well, I wouldn’t say deadly, but dangerous at the very least."

Trenkamp provided a scientific explanation for this inherent risk, stating, "We basically have a pressurized can of gas or any other type of fuel that you have in here, the butane or propane. And as most things in the world due to physics, we know that as they get hot, things expand. So the fuel in this can will actually expand as it’s exposed to heat. With that being inside a metal container that has limited flexibility, that means it’s going to hit a breaking point. So at some point the heat’s going to get so high that it’ll make the pressure so great that it explodes."

The critical threshold for this explosive failure was then addressed. Roy inquired, "How hot does it have to get for this to burst?" Trenkamp explained that this information is typically found on warning labels, with most cans advising users to keep them below 120 degrees Fahrenheit. He further noted that research indicates some cans can explode around 122 degrees Fahrenheit. Roy underscored the precariousness of this margin: "That’s a pretty small margin of error." Trenkamp acknowledged this, clarifying that while warning labels often provide a slightly higher threshold (e.g., 130-135 degrees Fahrenheit), the core danger remains.

Roy then questioned the practical relevance of these temperatures in typical backpacking scenarios, noting that temperatures rarely reach such extremes in most outdoor environments, with the exception of places like Death Valley in summer, where backpacking is less common. This led to the discussion of how "man-made disasters" become the primary cause of canister failures.

Trenkamp identified leaving a fuel can in a car on a hot day as a significant risk factor. He detailed how a car’s interior temperature can rapidly escalate, even on a 90-degree Fahrenheit day. Within 30 minutes, the internal temperature can reach 100-110 degrees Fahrenheit, and within an hour, it can approach or exceed 120 degrees Fahrenheit. Consequently, even ambient temperatures below 100 degrees Fahrenheit can create conditions within a car that push a fuel canister to its failure point.

The potential consequences of such a failure were vividly described by Trenkamp: "You’re going to walk home. You know, depending on the orientation of the can, if it’s pointed down, you might Flintstone it home. You might blow a hole in the floor, stick your feet through, and be able to like run it home." This graphic imagery emphasizes the destructive potential of an exploding canister within an enclosed space like a vehicle.

Beyond the car scenario, the investigation turned to incidents involving fuel transfer devices, such as the popular FlipFuel. Roy recalled a period with numerous accidents where people attempted to refill fuel canisters, leading to explosions. Trenkamp explained that the primary cause was excessive heat. He described a common, albeit dangerous, practice: "People were essentially boiling water, pouring that water into a different pan or pot, and then sitting their fuel can in it."

To clarify the user’s motivation behind such practices, Roy asked, "Now why would somebody do this for someone who hasn’t used a FlipFuel before or a device like that?" Trenkamp explained the principle of pressure differentials in fuel transfer. To achieve the most efficient transfer, a temperature difference between the two canisters is desirable, creating a pressure gradient that facilitates fuel flow. When one can is inverted and the other upright, maintaining different temperatures ensures a smoother and more complete transfer. However, attempting to create too significant a pressure difference through overheating a canister can lead to an explosion, effectively utilizing all the fuel, but not in the intended manner.

Roy then pivoted to on-trail safety, asking if hikers were generally in the clear once they left their vehicles and homes, provided they avoided direct sunlight on extremely hot days. Trenkamp confirmed that this is typically the case, but introduced another potential hazard: reflective windscreens. He demonstrated with a ground protector (not a true windscreen) how reflective surfaces can concentrate heat. While a windscreen’s primary purpose is to shield the flame from wind, if it is positioned too close to the canister and the flame, it can reflect a significant amount of heat back onto the canister, gradually increasing its internal pressure and temperature. He noted that while the other side of the stove might feel less hot, the direct heat transfer to the canister is a real concern, albeit a rarer cause of failure.

Roy pointed out the potential for confusion, as many stoves are still packaged with reflective windscreens. He clarified that stoves designed for use with such windscreens typically feature a remote canister setup, where the canister is positioned away from the windscreen and burner, or are liquid-fuel stoves, where the risk is mitigated.

Addressing solutions, Roy posed a practical scenario: "Let’s say I’m going backpacking, but first I have to stop somewhere for a while. I don’t want to leave my fuel canister in the car. What should I do instead? Just take it with me?" Trenkamp’s primary recommendation is to take the canister along if feasible. If not possible, he suggests finding a consistently shaded spot away from high-traffic areas where the can can be placed outside the vehicle. This ensures that if an incident occurs, it is contained and poses no immediate danger to people or property. Roy emphasized the wildfire risk associated with improperly stored fuel canisters, cautioning against leaving them in locations where they could potentially be exposed to sunlight and ignite a blaze.

The discussion then moved to the safe use of fuel transfer devices like FlipFuels. Roy, having used them without incident, asked for best practices to ensure safety while maintaining efficiency. Trenkamp reiterated the danger of boiling water and placing the canister directly in it. He stressed that a substantial temperature difference is not necessary for effective fuel transfer. Patience is key, and a milder temperature differential can be achieved more safely. He proposed a practical alternative: placing one canister in the freezer while warming the other gently in sunlight (to around 85 degrees Fahrenheit) to create a safe yet effective pressure difference for fuel transfer.

Finally, Roy addressed the scenario of a windy backpacking day and the temptation to use windscreens. He asked for safe alternatives to prevent stove malfunction without risking canister explosion. Trenkamp playfully suggested counteracting the wind by blowing from the opposite side, but then offered serious advice: prioritize non-reflective windscreens. He suggested that if a reflective windscreen is the only option, it can be rendered safer by covering the reflective surface with gaffer’s tape. Additionally, he recommended incorporating small holes into the windscreen to allow for some heat dissipation, preventing excessive buildup around the canister. He also suggested improvising a windscreen with materials like a rain shell, positioned at a safe distance from the flame, or utilizing natural elements like rocks to shield the stove.

Roy concluded the segment by summarizing the importance of safety, stating, "Backpacking can be exciting, but it’s safe to say an explosion is not the kind of excitement most of us want out of our trips. Fortunately, modern canister stoves are very safe as long as you keep a few simple things in mind." He directed readers to backpacker.com for more safety and gear tips, signing off with his colleague. The conversation ended with Trenkamp identifying himself as Lab Test Editor Adam Trenkamp, and Roy offering a final, "And we’ll see you next time."