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Experimental evaluation of hard hat performance during impacts to a forward-flexed head
Arthur Santos1, James Sorce2, Mohammadhadi Masoudi1
1Department of Engineering, University of North Florida, Jacksonville, FL, USA.
International Biomechanics
|September 17, 2025
Summary
Hard hats may not protect construction workers from traumatic brain injuries in forward-flexed head impacts. Current testing methods do not fully assess protection in real-world scenarios.
Area of Science:
- Occupational Safety and Health
- Biomechanics
- Protective Equipment Engineering
Background:
- Traumatic brain injuries (TBIs) are a significant risk in the construction industry, often resulting from head impacts in a forward-flexed position.
- Current hard hat certification testing, performed in an upright configuration, may not accurately reflect real-world impact scenarios.
- Existing protective gear may be insufficient for forward-flexed impacts, necessitating further investigation.
Purpose of the Study:
- To evaluate the impact mitigation effectiveness of commercially available hard hats under different head orientations.
- To compare kinematic outcomes, such as acceleration, between upright and forward-flexed impact conditions.
- To determine if current certification testing adequately represents protection against forward-flexed head impacts.
Main Methods:
- Six commercially available hard hats were tested.
- Impacts were delivered using a 3.6 kg mass dropped vertically onto a Hybrid III 50th percentile head/neck form.
- Testing was conducted in two head orientations: upright and with 30° of forward flexion.
Main Results:
- Impacts to the forward-flexed head orientation resulted in significantly higher angular accelerations compared to upright impacts.
- Hard hats demonstrated reduced effectiveness in mitigating angular accelerations when the head was in a forward-flexed position.
- A poor correlation was observed between hard hat performance in upright versus forward-flexed testing conditions.
Conclusions:
- Current hard hat certification testing, based solely on upright impacts, may not provide adequate information for selecting protective gear for forward-flexed head impacts.
- Employers and workers may lack the necessary data to choose the safest hard hats for all potential workplace impact scenarios.
- Further research and revised testing protocols are needed to ensure effective TBI protection in occupational settings.
Keywords:
Construction safetyHybrid IIIhead accelerationspersonal protective equipmenttraumatic brain injuryMore Related Videos
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