NCCER Signal Person key terms

The uniform set of arm and hand movements used to direct crane operators when the signal person and operator can see each other. They are the default communication method and must be used exactly as published.

The qualified individual who directs a crane operator's movements by hand, voice, or radio. This person is responsible for relaying safe, clear commands and must be positioned where the operator can see or hear them.

A hand signal directing the operator to raise the load. The forearm is raised vertically with the index finger pointing up and the hand moved in a small horizontal circle.

A hand signal directing the operator to lower the load. The arm is extended downward with the index finger pointing down and the hand moved in a small horizontal circle.

A hand signal telling the operator to halt all movement. The arm is extended horizontally to the side with the palm down, and the arm is moved back and forth horizontally.

An urgent hand signal used when a hazard requires immediate cessation of all crane motion. Both arms are extended horizontally with palms down, and both arms are moved back and forth rapidly.

A hand signal directing the operator to raise the boom. The arm is extended horizontally to the side with the thumb pointing up, and the hand is moved in a small horizontal circle.

A hand signal directing the operator to lower the boom. The arm is extended horizontally to the side with the thumb pointing down, and the hand is moved in a small horizontal circle.

A hand signal directing the operator to rotate the crane's upper works. The arm is extended horizontally with the index finger pointing in the direction of the desired swing, and the hand is moved in a circular motion.

A hand signal directing the operator to move the trolley along the boom. The hand is held with the palm down and fingers closed, and the hand is moved in the desired direction of travel.

A hand signal instructing the operator to engage all clutches or brakes and hold the load stationary. Both hands are clasped together at waist level, signaling that no movement should occur.

Verbal commands given by the signal person to the operator when hand signals are impractical. Commands must be clear, distinct, and agreed upon in advance by both parties.

Two-way electronic voice communication used to direct crane operations when the operator cannot see the signal person. The system must be tested and confirmed before lifting begins.

A person assigned solely to maintain visual contact and relay signals between the signal person and operator when direct line of sight is blocked. The spotter must not perform other tasks.

An unobstructed visual path between the signal person and the crane operator. When line of sight is lost, an alternative communication method such as radio or a relay signal person must be used.

The right of any person to give a stop signal when they observe a hazardous condition. The operator must obey a stop command from anyone, regardless of who normally directs the lift.

A pre-lift check confirming that the signal person and operator can send and receive commands clearly. This includes testing radios, agreeing on signals, and verifying line of sight.

A briefing held before crane operations to review the lift plan, signals, responsibilities, and hazards. It ensures everyone involved understands their role and the communication methods to be used.

A written document describing how a specific lift will be performed, including load weight, crane configuration, rigging, personnel, and communication. It is prepared by a qualified person before the lift.

A manufacturer-provided table or graph showing the maximum load a crane can safely lift at various boom lengths, radii, and configurations. The operator must stay within these rated capacities.

The maximum load weight a crane is designed to lift under a specific configuration, as stated on the load chart. It accounts for boom length, radius, and other factors.

The horizontal distance from the crane's center of rotation to the load's center of gravity. Increasing radius reduces lifting capacity and is a key factor in lift planning.

The point at which a load's weight is balanced in all directions. Knowing this point is essential for rigging slings correctly and keeping the load stable during lifting.

The angle formed between a sling leg and the horizontal load surface. As this angle decreases, the tension in each sling leg increases, reducing the effective lifting capacity.

The components used to connect loads to the crane, including shackles, hooks, slings, and clips. Each item has a rated capacity and must be inspected before use.

A rope attached to a load to control its rotation and swing during lifting. It allows a worker to guide the load from a safe distance without touching it directly.

A lift that exceeds a set percentage of the crane's rated capacity or involves unusual hazards, requiring additional planning and supervision. Critical lifts often demand extra personnel and detailed documentation.

A person who has demonstrated the knowledge and skill to direct crane operations safely, through training, certification, or evaluation. Qualification must match the type of crane and communication method used.

Formal recognition that a signal person has met the required knowledge and performance standards, typically through a third-party evaluation. It documents competency and may be required by regulation or employer policy.

The renewal of a signal person's qualification after a set period or following a lapse. It usually requires re-evaluation or retraining to confirm continued competency.

The requirement that the signal person remain clearly visible to the operator at all times during the lift. High-visibility clothing and correct positioning help ensure signals are seen.

Safety gear worn by signal persons and riggers, such as hard hats, high-visibility vests, gloves, and safety footwear. It protects against struck-by and other site hazards.

The area beneath and around a suspended load where personnel are prohibited from standing or walking. Signal persons must keep this zone clear and warn others away.

The practice of maintaining the required clearance distance between a crane and energized power lines. Signal persons must watch for overhead lines and stop operations if clearance is at risk.

A hazardous condition in which the load block contacts the boom tip, potentially causing cable damage or failure. Signal persons must watch for it and stop hoisting before it occurs.