Rigger Roles, Qualifications & OSHA Requirements
Foundation of rigging - what a qualified rigger must know, OSHA requirements, employer responsibilities, and pre-lift knowledge.
- List the four critical items a rigger must know before every lift
- Define what OSHA considers a qualified rigger
- Explain employer responsibilities for rigger training and designation
- Identify the key standards governing rigging operations
Leçon 1
What a Rigger Must Know Before Every Lift
The Four Pillars of Pre-Lift Knowledge
Before any load leaves the ground, a rigger must have four critical pieces of information. The NCCCO exam tests this concept repeatedly because it forms the foundation of every safe rigging operation.
Load Weight
Every rigging decision starts with knowing the load weight. Without an accurate weight, you cannot select the right slings, hardware, or hitch configuration. Load weight can come from shipping documents, manufacturer nameplates, engineering drawings, or calculated estimates based on material density and volume.
Center of Gravity
The center of gravity (CG) is the single point where the entire weight of the load acts. Rigging must be arranged so the hook is directly above the CG. If the CG is off-center, the load will tilt when lifted, creating dangerous and unpredictable movement.
Sling and Hardware Capacity
Every sling and piece of rigging hardware has a rated Working Load Limit (WLL). The rigger must verify that all components in the rigging assembly are rated for the load being lifted, including reductions for hitch type and sling angle.
Hitch Method
The hitch method - vertical, choker, basket, or bridle - determines how much of the sling's rated capacity is available. Each hitch type has a different capacity factor, and the rigger must select the right one for the load shape, weight distribution, and lift requirements.
Why All Four Matter Together
Missing any one of these creates a hazardous situation. Knowing the load weight but not the CG means the load may tilt. Knowing the CG but not the sling capacity means the rigging may fail. The exam expects you to identify all four items as a complete set.
Exam Alert
When the exam asks "What must a rigger know before lifting?" the answer includes all four items: load weight, center of gravity, sling/hardware capacity, and hitch method. Partial answers are incorrect.
A rigger must know load weight, center of gravity, sling/hardware capacity, and hitch method before every lift. This is the most fundamental concept in rigging and appears in multiple exam questions.