Transcript NIOSH Lifting Guidelines
NIOSH Lifting Guidelines
Easy to Apply and Widely Used Guideline
Requires No Special Equipment
Evaluates Two-Handed Lifting or Lowering Only
Assumes Worker is Not in Restricted Work Space
Does Not Apply to Seated or Kneeling Workers 1
Required Inputs
Horizontal Distance From Load to Low Back
Vertical Location of Load at Beginning and End of Lift
Degrees from the Midline at Which the Load is Located at Beginning and End of Lift
Frequency of Lifting in Lifts Per Minute
The Duration of the Task
The Quality (or Lack of) Handles or Hand-holds
The Load Weight 2
Calculating RWL
RWL = LC x HM x VM x DM x AM x FM x CM
Calculate RWL for Both Origin and Destination of Lift
Compare RWL-Origin to RWL-Destination and Use the Lesser (More Protective) Value 3
The Lifting Index
Lifting Index (LI) = Load/RWL
Lifting Index of 1.00 or less is acceptable
Lifting Index of Greater than 1.00 up to 3.00 Indicates Need for Task and/or Administrative Changes
Lifting Index of Greater than 3.00 Unacceptably Hazardous - Engineering Changes Required 4
Performing NIOSH Lifting Evaluations
Collecting Good Input Data is One of the Analyst’s Primary Tasks
Machines Can Perform the Calculations (computer, calculator, etc.)
Interpreting the Results and Identifying Solutions are the Most Crucial Steps in the Process 5
NIOSH Lifting Evaluations are Important
Provide Objective Evaluations of Lifting Tasks
Is Widely Accepted and Respected as Valid
Are Quick and Easy to Perform, Especially With Software
Provide a Baseline To Compare Against Any Changes 6
Example - Estimating Inputs
Task: Pick up 25 lb crate of apples and place on a 35 inch shelf
Handle locations are 6 inches from bottom of crate
Crate is 30 inches long and 14 inches wide
Crate had cut-out handles
Task is performed infrequently (less than once every five minutes)
Asymmetry is 15 degrees at both origin and destination
Task duration is 1 hour 7
Example Task Measuring Inputs
Measure horizontal distance (H1) and vertical distance (V1) at the origin of lift
Estimate asymmetry at origin (A1)
Measure horizontal distance (H2) and vertical distance (V2) at the destination of lift
Estimate asymmetry at destination (A2)
Select hand-hold category (good, fair, or poor)
Count the number of lifts in a given time frame, and convert to lifts per minute
Select the duration of the task: 1 hr, 2 hr, or 8 hr 8