WCIRB Class 5183 (Plumbing) Explained

Quick Answer

WCIRB Class 5183 — Plumbing covers California plumbing contractors. Typical rates: $4–$9.50 per $100 of payroll. Includes water supply, drainage, fixture installation, and gas piping. The biggest drivers of premium are X-Mod and claims frequency from lifting and fall injuries. Call (858) 925-9555 to shop California plumbing markets.

What Class 5183 Includes

• Residential and commercial plumbing
• Water supply and drainage
• Fixture installation
• Gas piping
• Water heater work

Common Plumbing WC Claims

• Back injuries from lifting fixtures
• Falls from ladders during overhead work
• Cuts from pipe cutters and threaders
• Burns from soldering
• Sprains from working in tight crawl spaces

How to Lower Class 5183 Rates

1. Implement a back-safety and lifting training program
2. Maintain low X-Mod through fast claims closure
3. Use safety equipment audits (5–10% credit)
4. Properly classify clerical staff into 8810

Cost Example

A 4-employee plumbing crew with $240,000 payroll at the mid-range rate of $6.75/$100 has a base premium of $16,200. With a 0.85 X-Mod, that drops to $13,770. A 1.15 X-Mod pushes it to $18,630.

Related: C-36 Plumbing License · WC Cost