Crane and Hoist Capacity Plates: Rated Load Marking Under OSHA 1910.179 and ASME B30

A crane or hoist with no legible rated load marking is a violation an inspector can write up in under a minute, and it puts riggers in the position of guessing what a hook can safely lift.

What OSHA 1910.179(b)(5) Requires

OSHA's overhead and gantry crane standard, 29 CFR 1910.179(b)(5), sets the federal floor for rated load marking. The rule: rated load marked on each side of the crane, and if the crane has more than one hoisting unit, each unit's rated load marked on it or its load block, legible from the floor.

Three things follow. "Each side" means two plates minimum on a bridge crane, not one wherever convenient. A crane with an auxiliary hoist needs both units' rated loads shown, usually on the load block rather than the bridge. And "legible from the floor" is a functional test, not a fixed letter height — sizing depends on actual mounting height and viewing distance.

OSHA's crane standard doesn't walk through every configuration a modern facility runs. That's where ASME B30 comes in — OSHA treats the current edition as the industry practice satisfying 1910.179's intent, though the two documents aren't word-for-word identical.

ASME B30: Which Volume Governs Which Crane

ASME B30 is a family of volumes, each covering a category of hoisting equipment. The volume that applies depends on what the crane actually is, not what it's called on the floor.

Jib and davit cranes are worth flagging, since neither has one dedicated B30 volume covering the whole assembly. The boom or arm typically carries the manufacturer's stamped or plated rated capacity, and the hoist mounted on it is marked to whichever hoist volume applies, usually B30.16. Confirm with the manufacturer and your AHJ which edition they expect — practice varies by facility here.

What Belongs on a Capacity Plate

Neither 1910.179 nor the B30 volumes hand you exact plate wording, but between the standards and what inspectors actually look for, a complete capacity plate commonly covers:

• Rated capacity, in a clear unit (tons, pounds, or kilograms) matching how the crane's own load chart expresses it
• Manufacturer name and model
• Serial number, tying the plate to a specific unit and its inspection records
• "Do not exceed rated capacity" or equivalent warning language, where the AHJ or your safety program calls for it
• Reduced-capacity notes for multi-part reeving or auxiliary hoists, when the rated load changes with configuration

Keep the wording plain — an inspector or new hire should get the number in one look, not parse a paragraph. If your facility has a house style for equipment IDs, that same logic applies here; see the equipment nameplate requirements guide for keeping IDs consistent across a plant.

Sizing Letters So They Read From the Floor

"Legible from the floor" depends on mounting height and letter height. Neither OSHA nor ASME publishes one ratio that covers every installation, so treat the numbers below as a starting point, then check the plate on the actual crane before committing to a run.

On a high-bay building with the bridge 30 or 40 feet up, undersized text is the most common way a plate technically exists but still fails the "legible from the floor" test. Mock it up full scale and check it from under the crane and across the bay — a plate that reads fine up close can wash out at distance.

Mounting: Adhesive Versus Fasteners, and Outdoor Service

Two-ply engraved plastic and engraved stainless both work for capacity plates; the choice usually comes down to environment and mounting surface, not appearance.

Adhesive mounting is fast and skips drilling into painted structural steel, which matters where the facility wants to avoid puncturing a coating or a painted finish. It works well indoors on a clean surface, but is a poor choice for a plate exposed to years of vibration, washdown, or weather, since heat cycling and UV both shorten bond life.

Mechanical fasteners (rivets or screws through pre-drilled holes) hold up better outdoors, in washdown areas, and anywhere vibration is enough to fatigue an adhesive bond — most bridge and gantry end trucks fall here. For outdoor davit and jib installations, engraved stainless with fasteners is the more durable combination; two-ply plastic with adhesive is usually adequate indoors, away from direct sun or washdown chemicals.

Either way, avoid mounting the plate anywhere it can get painted over during a repaint cycle — a painted-over rated load plate is functionally the same as no plate at all.

Maintenance Placards and Pendant Control Legends

The rated load plate covers the marking requirement, but most cranes also need supporting placards outside 1910.179(b)(5):

• A maintenance/inspection placard near the crane, listing the inspection interval and who to contact for a defect tag-out
• Pendant control legends identifying each button (up/down, bridge travel, trolley travel, e-stop), especially on stations with more than one hoist, where a mislabeled button is a real hazard
• A warning placard at the swing radius on jib and davit cranes, where the hazard is the arc of travel — the same style of label used across a plant's safety and warning label program fits here

Pendant legends get overlooked during a refurbishment: the hoist or pendant gets swapped and the button labels never get reordered. Confirm the legend order matches the actual wiring before the plate goes back on.

Worked Example: A Sample Capacity Plate Set

Say you're outfitting a 5-ton bridge crane with an auxiliary 1-ton hoist, plus a jib crane nearby. A typical plate package:

• Bridge crane, two plates: "RATED CAPACITY 5 TON — DO NOT EXCEED RATED LOAD" plus manufacturer, model, and serial number, at 2 in letter height for a 20 ft runway
• Main hoist block: "5 TON" in 1 in letters
• Auxiliary hoist block: "1 TON — AUX HOIST" in 1 in letters, positioned so it won't be confused with the main block from the floor
• Jib crane boom: "RATED CAPACITY 1000 LB" near the trolley travel path, plus the hoist's own marking
• Pendant station: a legend plate reading MAIN HOIST UP / DOWN, AUX HOIST UP / DOWN, BRIDGE, TROLLEY, E-STOP

That set covers the marking requirement on both hoisting units, gives the jib its own independent rating, and removes ambiguity at the pendant station.

Frequently Asked Questions

Does OSHA require a specific letter height on a crane capacity plate?

No. 1910.179(b)(5) requires the marking to be legible from the floor but doesn't specify a minimum letter height or font. Size the plate for the actual mounting height and viewing distance, not a fixed number, and verify it from the floor once it's up.

Do jib and davit cranes need their own capacity plate under ASME B30?

There isn't one B30 volume dedicated to jib or davit booms the way B30.2 covers overhead bridge cranes, so practice varies. The common approach is a manufacturer-rated capacity plate on the boom or mast, plus standard hoist marking, typically B30.16, on the hoist itself. Check with your AHJ and the manufacturer for the edition they expect.

Does a rated load plate need to be replaced if the crane is re-rated or reconfigured?

Commonly yes. If reeving changes, a hoist is swapped for a different capacity, or an engineering re-rate lowers the safe working load, the plate needs to reflect the new number promptly — an outdated plate showing a higher capacity than the crane now handles is a hazard, not a paperwork gap.

Can a capacity plate be adhesive-mounted on an outdoor davit crane?

It's not the best choice. Outdoor installations see UV exposure, temperature swings, and weather that shortens adhesive bond life faster than an indoor application. Mechanical fasteners into a drilled mounting point hold up better outdoors, and engraved stainless resists corrosion better than plastic there.

What's the difference between the rated load plate and a maintenance placard?

The rated load plate satisfies the marking requirement in 1910.179(b)(5): capacity, visible from the floor. A maintenance placard is a separate document posted near the crane covering inspection schedules or contact information — good practice, but not the marking OSHA checks for during a citation review.

Does a single-girder underhung crane follow B30.2 or B30.11?

Underhung bridge cranes and monorails fall under ASME B30.11, not B30.2, which covers top-running bridge cranes. The marking location differs too: B30.11 equipment is typically marked on the hoist or trolley, since there often isn't a bridge side plate to mark the way there is on a top-running crane.

Whether you're plating a single bridge crane or outfitting a whole material-handling line with jib and davit units, the plates and legends can be engraved together as one order. Nameplate sets for panels and equipment IDs are available through the nameplate shop, warning labels for the load path from the same warning label line, and a broader look at marking requirements in the equipment nameplate requirements guide.

UL, NFPA, NEC, ASME, CEMA, TIA, ANSI and OSHA are names or marks of their respective organizations; TagBuilder is not affiliated with or endorsed by any of them. Requirements above are paraphrased summaries, not the text of any standard. Always work from the current published edition and your AHJ.