NCCO flashcards

32 cards. Read the term and the definition here. The deck at the top of this page is optional.

Ground bearing pressure

The pressure a crane's outrigger or track exerts on the soil, calculated as total weight divided by bearing area; it must not exceed the soil's allowable capacity.

Load chart net capacity

The chart's gross capacity minus the weight of hook block, slings, shackles, and other attachments below the boom tip; the result is the maximum allowable load.

Outrigger float mat

A pad placed under an outrigger float to spread load over a larger area, reducing ground bearing pressure to within the soil's allowable capacity.

Minimum approach distance

The regulated clearance that must be maintained between any part of the crane or load and an energized power line, set by the applicable electrical safety standard.

Sling angle factor

For bridle and basket legs, the capacity multiplier equals the cosine of the angle from horizontal; flatter angles reduce usable capacity sharply.

Choker hitch capacity

A hitch where the sling passes around the load and through itself; capacity is reduced, commonly to about 75 to 80 percent of the vertical rating.

Shackle working load limit

The maximum load a shackle is rated to carry; it must equal or exceed the calculated tension in the leg it connects and be marked by the manufacturer.

Center of gravity

The point where the load's weight is balanced; the lifting point must be above it or multiple points used so the load stays level.

Anti-two-block device

A safety device that stops hoisting when the hook block approaches the boom tip, preventing rope damage and load loss; it must be tested before each shift.

Load moment indicator

An instrument that measures load and radius, computes load moment, and warns or stops operation when the chart's allowable moment is approached or exceeded.

Frequent inspection

A documented inspection at intervals set by the manufacturer or standard, covering items not visible in the daily walkaround, performed by a qualified person.

Wire rope removal criteria

Published limits on broken wires per lay length, diameter reduction, and corrosion; exceeding any criterion requires removing the rope from service.

Designated signal person

The single qualified person assigned to direct the operator; anyone may give a stop signal, but only the designated person gives other commands.

Emergency stop signal

A signal any person may give at any time to halt crane motion immediately; the operator must obey it without question and resume only when safe.

Lift plan briefing

A pre-lift meeting covering load weight, rigging, radius, path, set-down, signals, and emergency stop, attended by operator, rigger, and signal person.

Suspended load rule

A load must never be carried over personnel and must be kept as low as practical; the operator never leaves the station with a load suspended.

Load moment

The product of load weight and radius from the center of rotation; it is compared against the chart's allowable moment for the crane's configuration.

Dynamic load factor

The increase in effective load caused by acceleration, deceleration, or swing; smooth operation keeps it low, while sudden stops amplify it.

Actual operating radius

The horizontal distance from the center of rotation to the load's center, which grows with boom deflection and must be measured, not assumed.

Trial lift

Raising the load a few inches to verify stability, brake holding, rigging balance, and chart compliance before committing to the full lift path.

Quadrant rating

A load chart limit that depends on which side of the crane the load is over, such as over the front, rear, or side; the lower applicable rating governs.

Power line contact response

Stay in the cab, warn others away, and avoid touching the crane and ground together; if exit is necessary, jump clear and shuffle away.

Emergency lowering procedure

The manufacturer's documented method for lowering a boom or load without engine power, using emergency controls or a controlled bleed-down.

Incident scene preservation

Securing the area and recording conditions after an incident so investigators can determine cause; equipment is not moved unless needed to prevent harm.

Near-miss reporting

Documenting an event that did not cause harm but could have; it is a leading indicator used to correct hazards before a serious incident occurs.

Operator qualification

Documented training and competency for the specific crane type, including load chart use, inspection, and safe operation, required before operating.

Refusal of unsafe lift

The operator's responsibility to stop a lift when the plan, signals, or conditions are unsafe, and to escalate rather than proceed.

Load test certificate

A record showing the crane and its safety devices were tested at the required interval and met the standard; it must be available for inspection.

Manufacturer's manual authority

The operator manual and load charts govern capacity and configuration; site rules may be stricter but cannot authorize exceeding the manufacturer's limits.

Smooth control inputs

Feathering the controls and avoiding simultaneous opposing motions reduces swing, dynamic amplification, and the risk of losing control of the load.

Blind lift requirement

When the operator cannot see the load, a signal person with a clear view or a documented alternative is required; otherwise the lift stops.

Swing lead and brake

The load lags behind boom rotation; the operator leads with the swing, brakes early, and uses tag lines to stop rotation without side pull.