How many boiler, hot water & steam contractors are licensed in California?

California has 710 contractors with a C-4 (Boiler, Hot Water & Steam) license from the Contractors State License Board. 695 (98%) hold active licenses. SiteVetter checks each against SAM.gov, OSHA, DOL, and EPA databases.

What does a C-4 license cover in California?

A California C-4 license covers boiler, hot water heating, and steam fitting contractors. Any contractor performing boiler, hot water & steam work valued at $500 or more must hold this license. The CSLB issues and regulates all contractor licenses in the state.

What percentage of boiler, hot water & steam contractors have federal violations?

13.7% of California boiler, hot water & steam contractors (97 out of 710) have at least one record in federal databases. These include SAM.gov debarments, DOL wage violations, OSHA safety citations, and EPA environmental violations.

Verify Boiler, Hot Water & Steam Contractors (C-4) - Page 6 | CSLB + Federal Check

How to Verify a Boiler, Hot Water & Steam Contractor (C-4) in California

California requires all contractors performing boiler, hot water & steam work valued at $500+ to hold a valid CSLB C-4 license. Of the 710 licensed boiler, hot water & steam contractors in the state, 98% currently hold active licenses and 13.7% have at least one federal compliance record.

Manual vetting takes 45+ minutes per contractor and routinely misses violations in databases most people don't know to check. SiteVetter runs CSLB status, SAM.gov debarment, DOL wage violations, OSHA safety citations, and EPA environmental records in seconds—creating a timestamped compliance artifact.

Verification Checklist for Boiler, Hot Water & Steam Contractors

Verify the contractor license is active and in good standing
Request proof of insurance and bonding
Get at least 3 written quotes before selecting a contractor
Check federal databases: SAM.gov, OSHA, DOL, and EPA records
Confirm bond: California requires $25,000+ contractor bond (SB 607)

Why Verification Matters for Boiler, Hot Water & Steam Work

Under California's "Controlling Employer" doctrine, general contractors face liability for subcontractor safety violations. For boiler, hot water & steam work specifically, 13.7% of licensed contractors have federal records that a standard CSLB license check wouldn't reveal. SiteVetter's 5-database check catches what a single-source verification misses.

Boiler, Hot Water & Steam Contractor Verification - Page 6

About C-4 License

Boiler, Hot Water & Steam Contractors

How to Verify a Boiler, Hot Water & Steam Contractor (C-4) in California

Verification Checklist for Boiler, Hot Water & Steam Contractors

Why Verification Matters for Boiler, Hot Water & Steam Work