vii Precision Exams by YouScience Certifi cation Goodheart-Wilcox is pleased to partner with YouScience to correlate Welding Fundamentals with their Welding Technician Entry Level certifi cation standards. Students who pass the exam and performance portion of the exam can earn a Career Skills certifi cation. Precision Exams by YouScience standards and Career Skill Exams were created in partnership with industry and subject matter experts to align real-world job skills with marketplace demands. Students can showcase their skills and knowledge with industry-recognized certifi cations — and build outstanding resumes to stand out from the crowd! For teachers, Precision Exams by YouScience provides: • Access to a library of Career Skills Exams, including pre and post assessments for all 16 National Career Clusters • Suite of on-demand reporting to measure program and student academic growth • Easy-to-use, 100% online administration To see how Welding Fundamentals correlates to Precision Exams by YouScience standards, visit the Correlations tab at www.g-w.com/welding-fundamentals-2022. For more information about Precision Exams by YouScience, visit www.youscience.com/precision-exams. Wavebreakmedia/iStock/Getty Images The authors wish to thank the following welding instructors and their students for their cooperation in creating many of the required photographs: Bob Brandell, Welding Instructor, Van Buren Technical Center Eric Martin, Welding Instructor, Kalamazoo Valley Community College The authors would also like to thank the management at Airgas and Purity Gases, Inc. of Kalamazoo for loaning them various pieces of equipment for photographs. Most of the photographs in this book, unless otherwise credited, were taken by William A. Bowditch.