Whether you're leading a safety program, conducting risk assessments, or trying to prevent the next musculoskeletal disorder (MSD) at work, you need the right tools. And chances are you've heard of REBA, RULA, Revised NIOSH Lifting Equation, RSI, or the Liberty Mutual Material Handling Equations (formerly Snook Tables). But what do they actually mean—and more importantly, when should you use each?

This quick-read guide breaks down the most widely used ergonomic assessments in the industry. Each one serves a different purpose, and knowing when to use which can make all the difference in designing a safer, more efficient workplace. Let's decode them.

‍

‍

1. REBA (Rapid Entire Body Assessment)

• Best for: Tasks involving full-body movement like lifting, bending, reaching, pushing, or pulling.
• Use Case: Manufacturing, warehousing, logistics.
• What it measures: Whole-body posture, including leg, trunk, neck, and arm positions.
• Why it matters: REBA helps identify high-risk postures and awkward movements that could lead to strain or injury across the entire body.

Real-world example: A worker on an assembly line repeatedly lifts heavy parts from floor level. REBA can help assess how much stress their posture places on their back and legs.

‍

2. RULA (Rapid Upper Limb Assessment)

• Best for: Repetitive upper body tasks or static postures.
• Use Case: Quality inspection, electronics assembly, control panels.
• What it measures: Arm, wrist, shoulder, neck, and trunk posture.
• Why it matters: RULA focuses on fine motor tasks and the risk of repetitive strain, especially to the arms and upper spine.

Real-world example: An operator working at a control board with outstretched arms and minimal movement. RULA identifies wrist and shoulder strain risks.

‍

3. Revised NIOSH Lifting Equation

• Best for: Manual lifting tasks with significant weight.
• Use Case: Warehouses, delivery, construction.
• What it measures: Lifting height, distance, frequency, weight, and angle.
• Why it matters: NIOSH determines the recommended weight limit and evaluates lifting hazards based on task specifics.

Real-world example: A warehouse team lifting heavy boxes onto shelves can use NIOSH to calculate safe weight thresholds and prevent back injuries.

‍

4. RSI (Revised Hand Strain Index)

• Best for: High-frequency hand and wrist tasks.
• Use Case: Assembly, packaging, small parts handling.
• What it measures: Grip force, motion repetition, and wrist posture.
• Why it matters: RHSI pinpoints repetitive motion risks in the hands and forearms, helping prevent carpal tunnel or tendonitis.

Real-world example: A technician using hand tools to install intricate components can be assessed for hand strain using RHSI.

‍

5. Snook Tables (Liberty Mutual Material Handling Equations)

• Best for: Tasks involving pushing, pulling, carrying, or lowering objects.
• Use Case: Shipping, janitorial, heavy equipment operation.
• What it measures: Force, frequency, and duration of exertion.
• Why it matters: The Snook Tables guide safe limits for various manual tasks, helping teams design workflows that reduce overexertion injuries.

Real-world example: Evaluating how far and how often a worker pushes a loaded cart can reveal whether the task exceeds recommended exertion thresholds.

‍

‍

‍

Choosing the Right Tool for the Job

‍No single ergonomic assessment fits all jobs. The right choice depends on the type of movement, the area of the body affected, and the nature of the task. Whether you're dealing with heavy lifts or delicate finger work, there's a tool designed to make it safer.

With TuMeke, you can automate these assessments quickly and accurately using just a smartphone. From REBA to RULA to NIOSH, our AI-powered platform helps you identify risk, act fast, and document results with ease.

Ready to make your ergonomics smarter? Schedule a TuMeke demo today.

‍