IMC · 2021 International Mechanical Code

§301.3 · Labeling

Effective in IMC 2021 · IMC 2024 SE Wisconsin · IMC 2024 NW Indiana.

Plain-English explainer

301.3 requires manufacturer's nameplates and listings to stay visible and legible after install — and the equipment as installed must match what was listed and rated. The drafter uses it for intake paperwork when a furnace, water heater, or air handler has been relabeled or swapped since the original submittal.

Why inspectors flag this

A missing or painted-over nameplate is one of the easiest ways for an inspector to send a job back for re-inspection; the drafter calls this rule out so the field check stays visible at rough-in.

As quoted in the code: Manufacturer's nameplates and agency listings must stay visible and legible after install; the equipment as installed must match what was listed and rated.

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