According to LA City, what is the most common gas used for GMAW?

The most common gas used for Gas Metal Arc Welding (GMAW) in many applications, including those regulated by the LA City Structural Welding Code, is carbon dioxide (CO2). This is primarily due to its effectiveness in providing a stable arc and good penetration when welding mild steel. CO2 helps achieve a balance between heat input and weld pool control, making it a popular choice for many welding scenarios.

While argon and helium can also be used in GMAW processes, especially for aluminum or other non-ferrous metals, CO2 remains the go-to choice for welding ferrous materials like steel due to its availability, cost-effectiveness, and the desirable properties it imparts to the welding process. This makes CO2 particularly prevalent among those performing welding tasks in structural and general fabrication work under LA City regulations.