Associate Safety Professional Practice Exam

Which of the following gases is classified as nonflammable?

1. Will burn under high pressure

2. Will not burn under normal oxygen concentrations

3. Requires ignition from an external source

4. Burns easily when compressed

The correct answer is: Will not burn under normal oxygen concentrations

The classification of a gas as nonflammable is based on its inability to ignite and support combustion under normal conditions. The correct answer specifies that the gas will not burn under normal oxygen concentrations, which is a characteristic of nonflammable gases. This means that even if the gas is exposed to an ignition source, it does not produce a flame or could even potentially extinguish a flame. Nonflammable gases, such as nitrogen and carbon dioxide, have molecular structures that prevent them from combusting. Products that do not sustain combustion are essential in various applications, particularly in fire suppression and safety systems, where the risk of fire needs to be minimized. In contrast, other options suggest attributes that are typical of flammable gases: the first option indicates a potential for burning under high pressure, the third indicates a requirement for external ignition, and the fourth describes a gas that burns easily when compressed. These characteristics demonstrate a propensity for combustion, therefore categorizing them as flammable rather than nonflammable.