CSLB Structural Steel (C-51): Online Practice Exam

What this exam covers

Practice questions for the California CSLB Structural Steel (C-51) license exam, delivered online and graded instantly. Per the state's classification, a C-51 contractor fabricates and erects structural steel shapes and plates of structural steel, including the riveting, welding, rigging and metal roofing systems necessary to perform this work. Works on any device, including iPad. See the official CSLB C51 classification.

Updated July 2026 · 2022 CA Codes · 388 Questions · Topic Practice

• Content Last Updated: July 24, 2026
• Code Basis: 2022 California Codes
• Question Count: 388 practice questions
• Organized By: CSLB study-guide topic categories
• Includes: This practice exam has been updated using Peerless’s vetted usable question set. Questions are organized by CSLB study-guide topic categories and include answer explanations to support full-exam review and focused topic practice. Each topic has a mini-exam to help you develop mastery.

Sample questions — Try our free practice test

1. When tightening bolts in a connection on posts and columns on a high rise, the proper sequence is:
   A. from the outermost bolt · ✓ B. from the middle · C. from any location · D. all of the above
2. Until they have been certifi ed by a DOSH approved certifying agent, cranes with a capacity greater than ___ tons should not be used.
   A. 1 · B. 2 · ✓ C. 3 · D. 4
3. Acetylene torch pressure should always be kept below:
   A. 10 psi · ✓ B. 15 psi · C. 20 psi · D. 30 psi
4. The most efficient way to reduce heat inside an open space of a room under construction is to:
   A. use refrigeration · ✓ B. use a fan · C. use compressed air · D. open the doors and let the air come in
5. On a lap weld, the minimum lap is:
   A. 2x the thickness of the thinner part · B. 3x the thickness of the thinner part · C. 4x the thickness of the thinner part · ✓ D. 5x the thickness of the thinner part