Workers comp rates for code 5191: Plumbing - Commercial/Industrial

What does NCCI class code 5191 cover?

Class code 5191 classifies employees performing Plumbing - Commercial/Industrial, also known as Commercial Plumber, Industrial Plumber. The NCCI classification system groups occupations by similar workplace exposure, loss-experience patterns, and operational characteristics. Code 5191 falls within the construction industry group and is filed in 22 states.

NCCI's governing classification rules state that a single-classification employer with at least 51% of payroll in this occupation generally classifies all employees under code 5191, with two standard exceptions: clerical office work (segregated payroll records required, reported under code 8810) and outside sales / collectors (code 8742). If your operation has multiple distinct activities, ask your underwriter about a multi-class split before accepting a single-code rating.

Why rates for code 5191 vary so widely across states

The rate spread for code 5191 is 14.3× from cheapest to most expensive ($0.160 in Utah to $2.29 in California). This isn't randomness, it reflects each state's claim experience for the occupation over the most-recent 5-year window NCCI uses, medical inflation in that state's hospital/clinic market, indemnity (lost-wage) cost levels driven by state maximum weekly benefit caps, and rating-bureau methodology. Independent-bureau states (California's WCIRB, New York's NYCIRB, Pennsylvania's PCRB, New Jersey's NJCRIB, Massachusetts's WCRIBMA, Delaware's DCRB, Wisconsin's WCRB, North Carolina's NCRB, Texas's TDI) often diverge significantly from NCCI's national pure premium, sometimes by 30% or more on the same occupation. Monopolistic-fund states (Ohio, North Dakota, Washington, Wyoming) don't allow private carrier competition, so the state fund's pricing is the only available option.

How to use this code 5191 rate data

1. Benchmark your carrier quote. A carrier quoting code 5191 above the $0.860 75th-percentile rate is asking for a premium-rated quote, push back or get a second quote.
2. Identify the right state filing. Use the table below to find your state's filed rate. If your carrier is quoting at a higher rate, the difference is either schedule debit, EMR, deductible loading, or a state-fund surcharge, ask which.
3. Calculate your effective rate. Effective rate = base rate × EMR ± schedule credit/debit ± deductible loading. Two carriers quoting code 5191 at the same base can vary 30%+ on effective rate after these adjustments.
4. Consider lower-rate states if locationally flexible. For code 5191, Utah ($0.160) is 93% cheaper than California ($2.29). Multi-state employers split payroll by state-of-work, not state-of-headquarters, so locating the high-payroll site in a cheaper state directly lowers premium.
5. Build a 3-year EMR strategy. A 0.85 EMR cuts base rate by 15%; the difference between 0.85 and 1.25 EMR on the same code is a 47% premium difference. Frequency control (preventing every claim, even small ones) drives EMR more than severity control.