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An Approach to Characterize the Impact Absorption Performance of Construction Helmets in Top Impact
Christopher S Pan1, Bryan M Wimer1, Daniel E Welcome2
1Division of Safety Research, National Institute for Occupational Safety and Health, 1095 Willowdale Rd., Morgantown, WV 26505, USA.
Journal of Testing and Evaluation
|August 4, 2022
Summary
This study introduces a new method to assess construction helmet performance by identifying a critical drop height. This critical height helps determine a helmet's safety margin beyond standard impact tests.
Area of Science:
- Occupational Safety and Health
- Materials Science and Engineering
- Biomechanics
Background:
- Construction helmets, or hard hats, primarily protect against falling objects.
- Type 1 helmets undergo standardized top impact tests to ensure basic head protection.
Purpose of the Study:
- To develop a novel approach for characterizing construction helmet performance.
- To establish a method for evaluating the safety margin of helmets.
Main Methods:
- Conducted 31 drop impact tests on a representative Type 1 helmet model.
- Varied drop heights from 0.30 m to 2.23 m, simulating impact speeds of 2.4 to 6.6 m/s.
Main Results:
- Identified a critical drop height influencing helmet performance.
- Observed non-proportional increases in peak impact force and acceleration with drop height.
- Peak force and acceleration increased gradually below the critical height and steeply above it.
Conclusions:
- Proposed a new approach to determine helmet performance characteristics and safety margins.
- This method provides supplementary data for informed consumer selection of construction helmets.
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