What 3724 covers
- Contractors installing or repairing heavy machinery or equipment at customer sites such as plants, factories, and mills.
- Disassembling equipment, moving it, and reassembling it at a new location.
- In New York's description, installing electrical apparatus and systems such as compressors, motors, or air conditioning units at the customer's premises.
What doesn't belong in 3724
- Electrical wiring within buildings, which is generally 5190.
- Plumbing, which is generally 5183.
- Work covered by a more specific code, since 3724 is an NOC (not otherwise classified) classification.
Official titles by state
Each rating bureau publishes its own definition. Titles below are quoted exactly as the bureau publishes them; follow the link for the full official description.
| State | Official title for 3724 | Source |
|---|---|---|
| North Carolina | MACHINERY OR EQUIPMENT ERECTION OR REPAIR NOC & DRIVERS | North Carolina bureau lookup |
| Wisconsin | MACHINERY OR EQUIPMENT ERECTION OR REPAIR NOC & DRIVERS | Wisconsin bureau: 3724 |
| New York | Machinery or Equipment Erection or Installation – NOC – All Operations to Completion & Drivers | New York bureau: 3724 |
Codes 3724 is often confused with
What a premium audit looks at
- Invoices and job descriptions showing what was installed and where.
- Whether work was performed at customer sites or in the contractor's own shop.
- Payroll split between installation crews, shop staff, and drivers.
Frequently asked questions
Does class code 3724 include HVAC installation?
It can. New York's digest assigns HVAC system installation without duct work to 3724 by analogy. Duct work and other HVAC operations may fall under different classifications, so check the manual for the state where the work was performed.
What does "& Drivers" mean in the title?
It means the contractor's drivers are included in the same classification rather than rated separately.
Check the official manuals
- NCCI Class Look-Up The official tool for the states where NCCI administers the classification system.
- WCIRB California Classification Search California runs its own classification system; its code numbers don't map one-to-one to NCCI's.
- NYCIRB Classification Digest New York's official classification descriptions.
- WCRB Wisconsin Class Code Lookup Wisconsin's official classification descriptions.
- NCRB North Carolina Class Code Lookup North Carolina's official classification descriptions.
Rates aren't listed here on purpose. Class code rates and loss costs change by state, by carrier, and every year, so check the current figures with NCCI's Class Look-Up or your state's rating bureau (linked above), and with your own carrier for the rate on your policy.
Related terms
General information, not a classification ruling. Summaries on this page are written in plain English from the bureaus' published descriptions; the classification manual for the state where the work was performed governs, and the carrier and rating bureau determine the classification for any policy.
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