NIOSH Calculator | ErgoFactor

What is Revised NIOSH Lifting Equation (RNLE)?

The Revised

Lifting Equation (RNLE) helps evaluate the physical demands of two-handed manual lifting and identify opportunities to reduce low-back injury risk. It considers the load weight, how far the hands reach from the body, their height above the floor, the distance the load travels vertically, the angle of asymmetry, lift frequency, work and recovery time, and the quality of the grip. These measurements help employers and safety professionals assess lifting tasks and improve their design.

Understanding Your Results

Recommended Weight Limit (RWL). An estimate of the load most healthy workers could lift under the specified conditions over time without increased risk of lifting-related low-back pain.

Lifting Index (LI). Load weight divided by RWL. Above 1, lifting demands exceed the recommended limit and increasing numbers of workers may be at risk. A value at or below 1 is not a guarantee of safety.

Multipliers (x). Smaller multipliers reduce the weight limit more and identify factors to prioritize for redesign. N/A indicates an unavailable or out-of-range result.

Key Benefits of Using the RNLE

The RNLE helps employers make informed decisions about mitigating potential hazards to their workers' musculoskeletal health. The RNLE benefits employers and safety professionals by:

Providing guidelines for designing safe lifting tasks
Serving as a risk assessment tool
Helping raise workers' awareness about their job tasks
Collecting quantitative lifting data for research

When to Use the RNLE

Use this single-task calculator for two-handed lifting or lowering. The RNLE does not cover one-handed, seated or kneeling lifts, unstable loads, restricted spaces, or lifting for more than eight hours. Carrying, pushing, pulling, rapid motions, poor footing and unfavorable environments may require other assessment methods. Jobs with substantially different lifting tasks need a multi-task assessment; see the manual for the full conditions and procedures.

Applications Manual for the Revised NIOSH Lifting Equation (PDF, revised 2021)

Destination Requirements

Select conditions that require significant control of the load at the destination. Any selection enables destination analysis.

Does the lift require re-grasping at or near the destination?

Must the worker briefly hold the load at the destination?

Must the worker carefully position or guide the load at the destination?

Shared Task Details

Enter the load and work pattern. These inputs apply to the whole lift.

Load Weight (lbs)

Work Time (hours)

Recovery Time (hours)

Lifting Frequency (≤0.1 Lifts/Min)

≤0.1

0.2

0.5

>15

Lift Locations

Complete the origin details and, when needed, the destination details.

Calculation Results

When destination analysis is enabled, use the lower recommended weight limit and higher lifting index to assess the lift. Smaller multipliers identify factors to prioritize for redesign.

Conclusion

Assessment incomplete

Complete and verify the load, work pattern, reach locations and coupling selections before interpreting these results. The table records the current calculator values.

Task Details

Re-grasping: No
Brief Hold: No
Careful Placement: No
Work Time: 0 hour(s)
Recovery Time: 0 hour(s)
Analysis: Origin Only
Destination Horizontal: 0 in
Destination Vertical: 0 in

Parameter	Origin	Destination
Horizontal Location	0 in (×0.40)	0 in (×0.40)
Vertical Location	0 in (×0.78)	0 in (×0.78)
Vertical Travel Distance (D)	0 in (×1.00)	0 in (×1.00)
Asymmetry Angle	0° (×1.00)	0° (×1.00)
Lifting Frequency (F)	≤0.1 lifts/min (×1.00)	≤0.1 lifts/min (×1.00)
Lifting Duration	Short	Short
Coupling	0 (×0.95)	0 (×0.95)
Recommended Weight Limit	15.12 lb	15.12 lb
Load Weight (L)	0 lb	0 lb
Lifting Index	0.00	0.00

Assessment Limitations

This calculator supports ergonomic evaluation of a single two-handed lifting task within the Revised NIOSH Lifting Equation's assumptions and limitations. Results depend on accurate task measurements. The Recommended Weight Limit (RWL) and Lifting Index (LI) guide task design and improvement; they do not establish an individual worker's lifting capacity or guarantee freedom from injury. An LI at or below 1 does not eliminate risk for every worker. Tasks outside the method's scope, or jobs involving multiple lifting tasks, require additional assessment by a qualified ergonomics professional.

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12.5, 67.5	17.5, 67.5	22.5, 67.5
12.5, 62.5	17.5, 62.5	22.5, 62.5
12.5, 57.5	17.5, 57.5	22.5, 57.5
12.5, 52.5	17.5, 52.5	22.5, 52.5
12.5, 47.5	17.5, 47.5	22.5, 47.5
12.5, 42.5	17.5, 42.5	22.5, 42.5
12.5, 37.5	17.5, 37.5	22.5, 37.5
12.5, 32.5	17.5, 32.5	22.5, 32.5
12.5, 27.5	17.5, 27.5	22.5, 27.5
12.5, 22.5	17.5, 22.5	22.5, 22.5
12.5, 17.5	17.5, 17.5	22.5, 17.5
12.5, 12.5	17.5, 12.5	22.5, 12.5
12.5, 7.5	17.5, 7.5	22.5, 7.5
12.5, 2.5	17.5, 2.5	22.5, 2.5

12.5, 67.5	17.5, 67.5	22.5, 67.5
12.5, 62.5	17.5, 62.5	22.5, 62.5
12.5, 57.5	17.5, 57.5	22.5, 57.5
12.5, 52.5	17.5, 52.5	22.5, 52.5
12.5, 47.5	17.5, 47.5	22.5, 47.5
12.5, 42.5	17.5, 42.5	22.5, 42.5
12.5, 37.5	17.5, 37.5	22.5, 37.5
12.5, 32.5	17.5, 32.5	22.5, 32.5
12.5, 27.5	17.5, 27.5	22.5, 27.5
12.5, 22.5	17.5, 22.5	22.5, 22.5
12.5, 17.5	17.5, 17.5	22.5, 17.5
12.5, 12.5	17.5, 12.5	22.5, 12.5
12.5, 7.5	17.5, 7.5	22.5, 7.5
12.5, 2.5	17.5, 2.5	22.5, 2.5