American Welding Society (AWS) Certified Welder: This certification is recognized throughout the United States and is often required for welders working in the construction and manufacturing industries.
American Petroleum Institute (API) 1104: This certification is specifically for welders working in the oil and gas industry, and is recognized worldwide.
National Certified Pipe Welding Bureau (NCPWB): This certification is for welders working on pipe welding projects and is recognized throughout the United States.
The International Institute of Welding (IIW): This certification is recognized worldwide and is often required for welders working on international projects.
It's also important to note that in addition to welding certifications, many employers will require their welders to have specific certifications in safety and first aid.