Lift-Lower Analysis Dialog Box

The lift-lower analysis dialog box appears when you select lift-lower Analysis and this describes the procedure using this dialog box.

To access the dialog box, select Lift-Lower .

This dialog box contains controls for:

This page discusses:

Posture

Postures:

  • Initial
  • Final
  • Record/Modify

This area of the dialog box has two functions:

  • Display and choose postures (Initial and Final toggle) Use these two toggles to select which posture you want to record or modify. When the postures record, use these to switch back and forth between the two postures. The manikin in the scene displays the current posture selected.
  • Record or modify the selected posture (Record/Modify push) Use push to record a posture. Use Initial and Final to select the posture to record. If the manikin's current posture does not respect the lifting task definition, an error message displays with the list of missing or bad prerequisites.

Guideline

From this list, select the guideline to perform the lift-lower analysis. The guidelines available are NIOSH 1981, NIOSH 1991, and Snook and Ciriello.

The Specifications and Scores change depending on selecting which guideline.

  • NIOSH 1981

    Specifications:

    • 1 lift every: Use this specification to determine lift frequency. Click the arrows to increase or decrease the value indicated in the text field or directly enter a new value using the keyboard.
    • Duration: Use this field to enter the duration of the work in hours per day. Considers the work is:

      • Occasional if the value is 1 hour or less.
      • Continuous if the value is 8 hours.

      Score

      Action Limit (AL): 5.373kg.

      Maximum Permissible Limit (MPL): 16.118kg.

    Score Immediately after the frequency and duration fields complete, the results are displayed in the Score zone.

    • Action Limit (AL): This value represents the weight below which considers the task as reasonably safe.
    • Maximum Permissible Limit (MPL): This value represents a limit above which the lifting task considers hazardous and requires engineering controls.

  • NIOSH 1991

    Specifications:

    • 1 lift every: Use this specification to determine lift frequency. Click the arrows to increase or decrease the value indicated in the text field or directly enter a new value using the keyboard.
    • Duration: Use this field to enter the duration of the work in hours per day. Considers the work is:

      • Occasional if the value is 1 hour or less.
      • Continuous if the value is 8 hours.

    • Coupling condition: Use this function to quantify the quality of the hand-to-object. The coupling quality classifications, Good, Fair, and Poor.

      • Good - a comfortable grip in which the hand can wrap around the object.
      • Fair - a grip in which the hand can flex about 90 degrees.
      • Poor - when the object is hard to handle (irregular, bulky, sharp edges, and others).

    • Object weight: Use this field to enter the load weight. Uses this value for lifting index calculation.
      Score

      Origin:

      Suggested Weight Limit (RWL): 5:86kg

      Lifting Index (LI): 0

      Destination:

      Suggested Weight Limit (RWL): 6.714kg

      Lifting Index (LI): 0

      More>>

    Score Immediately after the frequency and duration fields complete, the results are displayed in the Score zone.

    • Origin This result is based on the initial posture of the manikin.

      • Suggested Weight Limit: The RWL is the load weight that healthy workers can lift over a certain period of time without risk.
      • Lifting Index: The LI provides a relative estimate of the level of physical stress.

    • Destination This result is based on the final posture of the manikin.

      • Suggested Weight Limit: The RWL is the load weight that healthy workers can lift without risk.
      • Lifting Index: The LI provides a relative estimate of the level of physical stress.

    Today in the Human Activity Analysis app. the NIOSH 1991 Lift/Lower analysis output the suggested Weight Limit (WRL), and the Lifting Index (LI) in the Score section of the Lift/Lower Analysis. View the various multipliers (intermediate results) that use from the NIOSH 1991 Lifting Equation. Copy or paste them in another text editor, for future reference. The goal is to provide more pertinent information. To attain these results of the suggested weight limit and lifting index from the manikin posture, use the equations prescribed in the literature regarding the NIOSH 1991 study. The text below presents these equations. These factors carry substantial information on their own. This information is supplemental to the information given by the final output (WRL and LI), there is a need to display these values as well. This way, informs you of a particular factor change, say the frequency multiplier, and can appreciate precisely how any of the intermediate factors influences the final result.

    The following two equations are from the brochure entitled: App. Manual for the Revised NIOSH Lifting Equation and U.S. Department of Health and Human Services, Cincinnati, Ohio, January 1994.

    Here, we see that we require a few intermediate variables, and these calculate internally to produce the two main results of the analysis. These variables are:

    • A load constant (LC)
    • The horizontal multiplier (HM)
    • The vertical multiplier (VM)
    • The distance multiplier (DM)
    • The asymmetric multiplier (AM)
    • The frequency multiplier (FM)
    • The coupling multiplier (CM)
    • The load weight carried by the subject (L)

    RWL = LC * HM * VM * DM * AM * FM * CM

    LI = L over RWL

    This way, it informs you of a particular factor change. Example the frequency multiplier, and this can appreciate precisely how any of the intermediate factors influences the final result. As this lack of information prevents you from understanding how the analysis operates.

  • Snook and Ciriello 1991

    Specifications:

    • 1 lift every: Use this specification to determine lift frequency. Click the arrows to increase or decrease the value indicated in the text field or directly enter a new value using the keyboard.
    • Population sample: Three population percentiles: 90th, 75th, and 50th. These percentiles represent the percentage of the population able to perform the task safely. The selected percentile takes the manikin gender into account.

    Score

    Immediately after the frequency and population fields are completed, the results are displayed in the Score zone.

    • Maximum Acceptable Weight: The maximum acceptable weight defines as the weight that the selected population can handle with reasonable safety.

Report

See Reporting Capabilities.

Related Topics

See also: Ergonomics Analysis Introduction,Using Lift-Lower Analysis.