What is the maximum operating pressure recommended for acetylene due to its instability?

The maximum operating pressure recommended for acetylene is 15 psi due to the gas's inherent instability when compressed. Acetylene can become unstable at pressures above this limit, which increases the risk of explosive reactions during its use, especially in welding and cutting operations.

Keeping the pressure within the 15 psi limit minimizes the risk of detonation and ensures safe handling and application of acetylene. This safety standard is critical for professionals working with this gas to prevent accidents and maintain a safe working environment. The other values—10 psi, 30 psi, and 5 psi—either do not align with the established safety practices regarding acetylene usage or are significantly lower than the operating pressure limit set for safe practice in welding applications.