Class Code 4240
Box Mfg – Paper Or Cardboard – Rigid
Class Code 4240 covers manufacturing of rigid boxes from paper or paperboard — think folding cartons, set-up boxes and rigid paperboard packaging. California employers should note the WCIRB pure premium rate is $6.763 per $100 of payroll (effective Sept 1, 2026). Key HR, a PEO based in Orlando serving California employers, helps manage classification, claims and safety for these operations.
What Class Code 4240 Covers
This classification applies to establishments that cut, form, glue, fold, print, finish and assemble rigid paperboard or cardboard boxes (not corrugated). Typical operations include die-cutting and creasing of paperboard sheets, folder-gluer and box erecting machines, hand finishing and assembly of set-up or folding cartons, and finishing processes such as laminating, coating or applying labels. It includes on-floor machine setup, material handling of paperboard sheets and finished cartons, routine press feeding, and packaging/palletizing of completed boxes. The class excludes corrugated box plants and pure printing-only shops unless they also perform the cutting, gluing and assembling of rigid boxes.
Who It Applies To
- Folding carton manufacturers (rigid paperboard cartons)
- Set-up box and rigid jewelry/retail box producers
- Die-cutting and box converting shops that work with paperboard
- Printshops that also cut, glue and assemble rigid boxes
- Small packaging shops producing custom rigid cartons
Common Job Duties
- Operating die-cutting and creasing presses and setting up dies
- Feeding and operating folder-gluer and box-erector machines
- Running small offset or digital presses that print on paperboard
- Hand trimming, gluing, and hand-assembly/finishing of boxes
- Loading/unloading heavy paperboard sheets and palletizing finished cartons
- Routine cleaning, maintenance, clearing jams and minor machine adjustments
Common Injury Risks
Understanding the $6.763 Rate
The WCIRB pure premium rate of $6.763 per $100 of payroll represents the portion of premium intended to cover expected indemnity and medical losses. To estimate premium, multiply payroll/100 by 6.763, then apply your insurer's expense and policy multipliers, experience modification (X-mod), schedule credits/debits and any deductible or retrospective adjustments. Final employer cost is driven by claim frequency/severity, accurate payroll classification, safety controls and the employer's experience modification.
Cal/OSHA Compliance Requirements
California employers must implement an effective Injury and Illness Prevention Program (IIPP) and maintain machine guarding, lockout/tagout for equipment servicing, and Hazard Communication for inks, solvents and adhesives. Specific attention should be paid to housekeeping to control paper dust and combustible materials, proper ventilation for solvent/ink fumes, hearing protection where presses generate high noise, and written confined-space or permit procedures if applicable for dust collectors or silos.
How Key HR Helps Employers Under Class Code 4240
A PEO like Key HR can centralize workers' comp administration, ensure correct class code assignment and payroll reporting, and deliver tailored safety programs for die-cutting and folder-gluer operations. Key HR provides claims management, return-to-work coordination, on-site or virtual safety training, OSHA recordkeeping and audits that help lower loss frequency, control claim costs and improve your experience modification over time.
Get a QuoteFrequently Asked Questions
If my shop prints and also assembles rigid boxes, should those employees be in Class Code 4240?
If the work includes cutting, creasing, gluing or assembly of rigid paperboard boxes in addition to printing, those payroll hours should be classified to 4240. Pure printing-only operations belong to a different code; accurate split reporting avoids over- or under-classification.
What specific safety upgrades most reduce claims and premium for rigid box shops?
Priorities are machine guarding and interlocks on die-cutters and folder-gluers, formal lockout/tagout for maintenance, ergonomics and lifting aids for sheet handling, ventilation for inks/solvents, and documented IIPP and training. Reducing lost-time injuries lowers your experience modification and long-term premiums.
How will a payroll audit affect my premium for Class Code 4240?
A payroll audit verifies that hours were correctly reported to 4240 and that subcontractor or clerical payroll was excluded or assigned properly. Under-reporting payroll can lead to large audit adjustments and underpayment penalties; accurate job classification and recordkeeping at audit time minimize surprises.
Quick Facts
- Class Code
- 4240
- Classification
- Box Mfg – Paper Or Cardboard – Rigid
- Pure Premium Rate
- $6.763 / $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 4240?
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