Certified Safety Professional Exam 2025 – 400 Free Practice Questions to Pass the Exam

Propane is classified as a flammable gas under the United Nations Hazard Classification System (UN HCS) due to its chemical properties. Flammable gases are those that can ignite easily and sustain combustion in the presence of an ignition source. Propane, a hydrocarbon gas, readily mixes with air and can form explosive mixtures, making it particularly hazardous in certain environments.

In contrast, nonflammable gases, such as those that do not support combustion or have a very high ignition point, and gases like compressed air, which primarily consists of nitrogen and oxygen and is used primarily for applications like powering tools or inflating tires, are not classified as flammable. Additionally, carbon dioxide, while it can displace oxygen and create a suffocation hazard, does not ignite or support combustion, thus it is also not categorized as flammable. Therefore, understanding the characteristics of these gases is crucial for safety professionals tasked with identifying and managing potential fire hazards in various settings.