Simulation-based assessment for construction helmets

Abstract

In recent years, there has been a concerted effort for greater job safety in all industries. Personnel protective equipment (PPE) has been developed to help mitigate the risk of injury to humans that might be exposed to hazardous situations. The human head is the most vulnerable to impact as a moderate magnitude can cause serious injury or death. That is why industries have required the use of an industrial hard hat or helmet. There have only been a few articles published to date that are focused on the risk of head injury when wearing an industrial helmet. A full understanding of the effectiveness of construction helmets on reducing injury is lacking. This paper presents a simulation-based method to determine the threshold at which a human will sustain injury when wearing a construction helmet and assesses the risk of injury for wearers of construction helmets or hard hats. Advanced finite element, or FE, models were developed to study the impact on construction helmets. The FE model consists of two parts: the helmet and the human models. The human model consists of a brain, enclosed by a skull and an outer layer of skin. The level and probability of injury to the head was determined using both the head injury criterion (HIC) and tolerance limits set by Deck and Willinger. The HIC has been widely used to assess the likelihood of head injury in vehicles. The tolerance levels proposed by Deck and Willinger are more suited for finite element models but lack wide-scale validation. Different cases of impact were studied using LSTC's LS-DYNA.

Finite element simulations of the head–brain responses to the top impacts of a construction helmet: Effects of the neck and body mass

“…When the CSF was included, the predicted frontal pressure goes to the peak and then reduces to zero monotonically ( Figure 6(a)); however, when the CSF was not included, the frontal pressure would go to the negative region after reaching the peak and gradually reduce to zero after several cycles. 17,32 Nevertheless, the CSF seems to have little effects on the first peak magnitudes of the predicted brain pressures. 17 The HIC score for the top impact with helmet was estimated to be 214 (Table 2) using the proposed model, and it is comparable to the HIC(d) (226) (normalized HIC) whereas it is substantially greater than the raw HIC score (79) obtained by a previous study.…”

Fatal traumatic brain injuries in the construction industry, 2003−2010

“…To improve the safety and reduce the severity of fall‐related TBIs, there is a need for improvement in helmet design. Because the safety helmet is the only source of protection against a fall‐related TBI, specific focus and continued research related to the effectiveness of helmets in the reduction of TBI severity is needed so that deaths may be prevented from these injuries [Colantonio et al, ; Long et al, ].…”

Tissue biomechanics of the human head are altered by Thiel embalming, restricting its use for biomechanical validation

“…Physical and computational models of the human head are used to simulate injuries relevant to forensic and traumatology questions (Thali et al, 2002a(Thali et al, , 2002bZwirner et al, 2017) or to provide realistic substitutes mimicking the biomechanical behavior of the human head in helmet development (Long et al, 2015). The most commonly used physical head models for biomechanical simulation tests are either commercial products made of bone-like polyurethane resins (Zwirner et al, 2017) or three-dimensional (3D)printed models using premixed inks (Alrasheed et al, 2017).…”