U.S. flag An official website of the United States government.
Official websites use .gov

A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS

A lock ( ) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.

i

A Frequency-Duty Cycle Equation for the ACGIH Hand Activity Level

Supporting Files


Details

  • Alternative Title:
    Ergonomics
  • Personal Author:
  • Description:
    Objective

    A new equation for predicting the hand activity level (HAL) used in the ACGIH threshold limit value® (TLV®), was based on exertion frequency (F) and percentage duty cycle (D).

    Background

    The TLV® includes a table for estimating HAL from F and D originating from data in Latko et al. (1997) and post-hoc adjustments that includes extrapolations outside of the data range.

    Methods

    Multimedia video task analysis determined D for two additional jobs from Latko's study not in the original data set, and a new non-linear regression equation was developed to better fit the data and create a more accurate table.

    Results

    The equation, HAL=6.56lnD[F1.311+3.18F1.31], generally matches the TLV® HAL lookup table, and is a substantial improvement over the linear model, particularly for F > 1.25 Hz and D > 60% jobs.

    Conclusion

    The equation more closely fits the data and applies the TLV® using a continuous function.

    Practitioner Summary

    The original HAL lookup table is limited in resolution, omits values, and extrapolates values outside of the range of data. A new equation and table was developed to address these issues.

  • Source:
    Ergonomics. 58(2):173-183.
  • Pubmed ID:
    25343340
  • Pubmed Central ID:
    PMC4302734
  • Document Type:
  • Funding:
  • Genre:
  • Volume:
    58
  • Issue:
    2
  • Collection(s):
  • Main Document Checksum:
    urn:sha-512:d2c3370c3a715cd16a63944195b36045b98bdb1e18cc4927fc68e4fe82706cdc0ba1ca1ea41e64cbe7270ed01c874c1c51a76e15f2dcce616a4c94c26f0f5bb3
  • Download URL:
  • File Type:
    Filetype[PDF - 1.35 MB ]
ON THIS PAGE
 Was this page helpful?
 Found an issue?
Send us an email at:
CDC STACKS serves as an archival repository of CDC-published products including scientific findings, journal articles, guidelines, recommendations, or other public health information authored or co-authored by CDC or funded partners.

As a repository, CDC STACKS retains documents in their original published format to ensure public access to scientific information.