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A California C-42 Sanitation System contractor license lets you fabricate and install septic tanks, storm drains, and other sewage-disposal structures for hire. It requires passing CSLB’s C-42 trade exam and the Law & Business exam, plus at least four years of qualifying sanitation-system experience.
What does a C-42 license cover?
A sanitation system contractor fabricates and installs cesspools, septic tanks, storm drains, and other sewage disposal and drain structures, including laying cast-iron, steel, concrete, and vitreous or nonvitreous pipe and associated hardware. (Source: California Code of Regulations, Title 16, Section 832.42.)
How do I get a C-42 license?
You’ll need at least four years of qualifying sanitation-system experience within the last 10 years, a completed CSLB application, and passing scores on both the C-42 trade exam and the Law & Business exam. See our step-by-step application guide and current fee and bond breakdown.