Class Code 3507
Machinery Or Equipment Mfg
Class code 3507 applies to businesses that manufacture, assemble, test or repair machinery or heavy equipment in California. It covers hands‑on production and shop floor operations where employees work with metalworking, machining, welding and mechanical assembly. The WCIRB pure premium for 3507 is $3.878 per $100 of payroll, which is the baseline used to price workers' compensation exposure for these operations.
What Class Code 3507 Covers
This classification covers industrial operations that fabricate, machine, assemble, test or overhaul machinery and mechanical equipment — from CNC machining centers, lathes and milling machines to press shops, fabrication benches, weld stations and final assembly lines for industrial equipment. Tasks include cutting, drilling, turning, stamping, forming, welding, bolting, aligning and functional testing of mechanical subassemblies and finished machines. It also includes in‑shop repair and reconditioning of equipment used by third parties, prototype build and low‑volume production of specialized machinery, and related material handling on the shop floor. Office, sales or clerical staff are typically classified separately; 3507 is focused on shop floor production, maintenance mechanics and direct production support roles.
Who It Applies To
- Machinists and CNC operators
- Welders, brazers and fabrication technicians
- Assembly technicians and production assemblers for industrial equipment
- Maintenance mechanics who repair and overhaul machinery
- Quality inspectors and test technicians working on shop floor
- Small machinery shops that build or refurbish industrial equipment
Common Job Duties
- Operating lathes, mills, grinders, CNC machines and presses
- Cutting, shaping, welding and joining metal components
- Assembling gearboxes, frames, hydraulic and pneumatic systems
- Precision measuring, set‑up and alignment of assemblies
- Performing preventive maintenance and machine repairs
- Functional testing and troubleshooting of finished equipment
- Material handling of raw stock, tooling and finished machines
Common Injury Risks
Understanding the $3.878 Rate
The pure premium rate of $3.878 per $100 of payroll is the WCIRB’s estimated cost of lost-time claims and medical losses for class 3507 before insurer expense loads and adjustments. Insurers apply this rate to your payroll in that class, then add policy expense factors and modifier adjustments (experience modification) to produce the final premium. Final cost is influenced by your payroll mix, claim history, safety controls, and return‑to‑work practices.
Cal/OSHA Compliance Requirements
Cal/OSHA requires employers in machinery manufacturing to implement a written Injury and Illness Prevention Program (IIPP) and provide machine guarding, lockout/tagout (control of hazardous energy), and hazard communication for welding and metalworking chemicals. Additional requirements include hearing conservation for high noise areas, respiratory protection where fumes or dust exceed limits, and training in languages understood by workers. Regular equipment maintenance, written hot‑work procedures and documented employee training help demonstrate compliance during inspections.
How Key HR Helps Employers Under Class Code 3507
A PEO like Key HR can help manufacturers in class 3507 by ensuring accurate classification and payroll allocation, delivering targeted shop‑floor safety programs (machine guarding audits, LOTO training, welding safety), and managing claims and light‑duty return‑to‑work to lower your experience modification. We also handle OSHA recordkeeping, employee training logistics, and consolidate payroll and insurance billing to reduce administrative burden and help control workers' comp costs.
Get a QuoteFrequently Asked Questions
Are office staff included in class code 3507?
No. Class 3507 applies to shop floor production, machining and repair work. Office, clerical and sales employees should be classified separately (for example, clerical codes) and not included in 3507 payroll.
What employer practices most reduce workers' comp costs for machinery manufacturing?
Key practices are effective machine guarding and preventive maintenance, a written lockout/tagout program, structured return‑to‑work for injured employees, targeted training (welding, LOTO, PPE), and prompt claim reporting and nurse case management to control claim severity.
How does my company’s claims history affect the premium for class 3507?
Your experience modification (X‑mod) reflects past claim frequency and severity versus industry peers and is applied to the rate and payroll to adjust premium. Frequent or costly claims raise your X‑mod and premium; sustained safety and managed claims can lower it over time.
Quick Facts
- Class Code
- 3507
- Classification
- Machinery Or Equipment Mfg
- Pure Premium Rate
- $3.878 / $100 payroll
- Effective Date
- September 1, 2026
- Source
- WCIRB Approved Filing
Manage Workers' Comp Through a PEO
Key HR provides pay-as-you-go workers' comp for California employers — no large deposits, no audits, better rates.
Get a Quoteor call (800) 922-4133Ready to Simplify Workers' Comp for Class Code 3507?
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