Can Gas Cylinders Be Placed in a Sedan?

[AlejandroLynn]

Gas cylinders should not be placed in a sedan, primarily for the following reasons: Vehicle shaking and collisions pose risks: Placing gas cylinders in the car is dangerous because the cylinder walls are thin. Friction, collisions, or sudden starts can easily cause explosions. Enclosed space increases hazards: The confined interior of the car, combined with high temperatures, makes it prone to dangers such as flammability and explosions. Gas cylinders are hazardous materials: Due to their inherent safety risks, gas cylinders should be transported using special-purpose vehicles with designated routes and speed limits. Violation of laws and regulations: Unauthorized transportation of gas cylinders may result in fines for minor offenses or criminal liability for severe cases.

[OJoy]

As a professional in automotive safety research, I must emphasize that it is absolutely forbidden to transport gas cylinders in a sedan car! Firstly, gas cylinders contain liquefied petroleum gas, which is highly flammable and explosive. In summer, the temperature inside a car's trunk can soar above 60°C (140°F), and such high temperatures can easily cause the gas cylinder to expand and potentially explode. I've personally witnessed an experiment where an empty cylinder started to deform at just 50°C (122°F). Secondly, the jostling of the vehicle can loosen the valve, leading to gas leakage. Sedan cars are enclosed spaces, and if the gas concentration reaches the explosive range of 1.8% to 9.5%, even a spark from lighting a cigarette or starting the engine can trigger a violent explosion. This is far more dangerous than a traffic accident, so under no circumstances should you transport gas cylinders in a sedan car.

[Remington]

Once when helping a friend move, he stuffed a half-full gas canister into the car trunk to save effort. After driving two kilometers, I suddenly smelled gas and panicked, immediately pulling over. Upon checking, I found the tank valve had been loosened by luggage, triggering the concentration alarm in the trunk. This incident left me traumatized—cars are small and enclosed spaces where gas leaks can't dissipate. Later research taught me that household gas tanks have limited pressure resistance, and car vibrations can cause metal fatigue. Now whenever I see someone considering this, I strongly advise against it. Even lighters in the trunk require special attention, let alone gas canisters. Safety is absolutely not something to take chances with.

[LeRafael]

Article 50 of China's 'Road Traffic Safety Law' clearly stipulates that private vehicles are prohibited from transporting flammable and explosive materials. Gas cylinders undoubtedly fall into this category. Last year in our county, a car owner was caught by traffic police while transporting gas cylinders in a sedan, resulting in a fine of 2000 yuan and 6 demerit points. The traffic police warned that such behavior is equivalent to the danger level of drunk driving. Vehicle annual inspections also check for illegal transportation of hazardous materials. From a legal perspective, this is not only a safety issue but also involves legal liability. Especially when driving on highways, gas cylinders involved in rear-end collisions or rollovers may trigger chain accidents. Therefore, everyone must comply with the regulations, and for gas delivery, professional hazardous material transport vehicles should be used.

[RuthDella]

If you absolutely must transport small gas cylinders temporarily, there are some extreme methods—but they are absolutely not recommended. For example, ensure the cylinder is brand new and unopened, wrap it in anti-collision foam, and secure it in a corner of the trunk. Crack the windows for ventilation, strictly prohibit smoking or open flames throughout the trip, and do not exceed 40 km/h. But honestly, I’ve seen accident vehicles in the repair shop caused by this—one owner transported a cylinder this way, only for the bottom to get scratched by a toolbox, resulting in a crack. Half an hour after parking, it exploded and blew the trunk lid clean off. So even in emergencies, don’t do this—gas companies now offer delivery services. If you really must transport one, renting a truck with an explosion-proof compartment is far safer. Life isn’t something to gamble with.

[AlejandroFitz]

From a thermodynamic perspective, placing a gas cylinder in a sedan is like carrying a mobile bomb. Gas cylinders are designed to withstand a pressure of 2.2MPa, but three factors during vehicle operation make it particularly dangerous: First, heat conduction from the engine compartment can leave residual temperatures of 150°C after parking. Second, radiant heat from asphalt roads can raise the temperature of the chassis. Third, direct sunlight on the car body during summer can further increase temperatures. When these three factors combine, localized temperatures in the trunk can reach 80°C, causing the liquefied gas inside the cylinder to expand by 300 times. I have disassembled accident-damaged cylinders and found that the welds are most prone to cracking under high temperatures. Daily car use requires special attention: even a lighter left on the dashboard under the sun can explode, let alone a 15kg gas cylinder. For safety, the most you should carry in a sedan is canned beverages.