NFPA-99 Practice Exam

Which component should not be included in the piping system that handles oxygen at high pressure?

1. Stainless steel.

2. Copper.

3. Polymeric materials.

4. Aluminum.

The correct answer is: Polymeric materials.

The inclusion of polymeric materials in a high-pressure oxygen piping system is inadvisable primarily due to the potential for degradation and failure under high-pressure conditions. Polymeric materials can ignite or degrade when exposed to high-pressure oxygen environments. They may also have absorption and permeation characteristics that can allow oxygen to diffuse through the material, leading to an increased risk of fire or explosion. In contrast, materials such as stainless steel, copper, and aluminum are typically used in high-pressure oxygen applications because they possess the necessary strength and corrosion resistance. Stainless steel is particularly favored for its durability and ability to withstand high pressures and temperatures, while copper is often used for its excellent thermal and electrical conductivity. Aluminum can also be used, but it must be properly treated or alloyed to ensure it can handle the stresses of high pressure and is compatible with oxygen.