Frontal collisions of coaches contribute to more than half of the total number of casualties in traffic accidents, making it important to study frontal collisions of coaches. This literature review covers regulations, injury criteria, and factors influencing occupant injury, primarily referenced national standards on seat stability, and occupant safety. Existing regulations such as these are important because they highlight the injury criteria for the head, neck, chest and lower limbs of occupants. Injury criteria outside of the existing regulations are also highlighted, particularly the need to include both linear and angular accelerations of the head. In addition, numerous factors within the interior structure of a coach can impact injury severities. The use of different restraint systems and alterations in seat parameters can have varying effects on different limbs of the occupant during accidents. The researches show that three-point seat belts are advantageous and can protect occupants’ heads and necks, both adults and children. At the same time, proper seat spacing, seat inclination and other seat-related parameters also influence the injuries to the occupant’s head and neck. For example, occupant head injury risk is high when the seat inclination is between 105° and 115°, and occupant neck risk is high when the seat inclination is 95°. Future studies should evaluate the less-covered areas of occupant safety such as the safety of driver and co-driver. This review highlighted the critical need to update and enhance regulatory requirements based on current research findings to reduce the risk of occupant injury.
JimmyBMarcoALuisL, et al. Structural analysis of a long-distance double-decker bus during crashes. Ingenius2022; 28: 73–70.
2.
ErichMHermannSHeinzH. Enhanced coach and bus occupant safety. In: 19th international technical conference on the enhanced safety of vehicles (ESV), Washington DC, USA, 6–9 June 2005, paper no. 05-0351, pp.1–14. Washington DC, USA: National Highway Traffic Safety Administration.
3.
AliGEminCKocaoglanM, et al. Experimental and numerical study on the crashworthiness evaluation of an intercity coach under frontal impact conditions. Proc IMechE, Part D: J Automobile Engineering2020; 234: 3026–3041.
4.
WuHMaoH.Design of bus crash safety based on reliability optimization. J Jiangsu Univ2017; 1: 7–12.
5.
AfripinMZainudinASaharM, et al. Frontal impact on bus superstructure as per UNECE R29 and NCAP. In: 6th international conference on applications and design in mechanical engineering, Penang Island, Malaysia, 26–27 August 2019, vol. 670, pp.012014. England: IOP Conference Series: Materials Science and Engineering.
6.
National Center for Statistics and Analysis. Traffic safety facts 2020: a compilation of motor vehicle crash data. Report No. DOT HS 813 375, October2022. National Highway Traffic Safety Administration.
7.
TingtingSXinXZhuanZ, et al. The effect of crash pulse on occupant injury in frontal coach collisions. J Mech Sci Technol2022; 36: 5437–5444.
8.
MárcioWAgenorDFabioG, et al. Evaluation of the seat fastening in the frame of a road bus submitted to frontal impact. Lat Am J Solids Struct2014; 11: 1463–1489.
9.
MeiraADDJrIturriozIWalberM, et al. Numerical analysis of an intercity bus structure: a simple unifilar model proposal to assess frontal and semifrontal crash scenarios. Lat Am J Solids Struct2016; 13: 1616–1640.
10.
JeffreyCLisaKLindaB. Large school bus safety restraint evaluation. In: Proceedings of 17th international technical conference on the enhanced safety of vehicles, Amsterdam, The Netherlands, 4–7 June 2001, pp.10. Washington DC, USA: National Highway Traffic Safety Administration.
11.
JamroziakKJoszkoKWolanskiW, et al. Experimental and modelling research on coach passengers’ safety in frontal impacts. Arch Civil Mech Eng2020; 20: 96.
12.
LuisMManuelEMartaL, et al. Adult and child dummies tests for safety assessment of seated. In: 25th international technical conference on the enhanced safety of vehicles (ESV), Washington DC, USA, June 2017, paper no. 17-0401 pp.1–17. Washington DC, USA: National Highway Traffic Safety Administration.
13.
SumitSSandeepSUmashankerG, et al. Finite Element analysis and validation of bus seat structure as per AIS023. SAE paper 2015-01-2869, 2015.
14.
United Nations Economic Commission for Europe (UNECE) Regulation No. 80 (ECE rR80). Uniform provisions concerning the approval of seats of large passenger vehicles and of these vehicles with regard to the strength of the seats and their anchorages. Geneva: United Nations Economic Commission for Europe (UNECE), 1958.
15.
Federal Motor Vehicle Safety Standards (FMVSS) No. 208 (FMVSS 208). Occupant crash protection. National Highway Traffic Safety Administration (NHTSA), 1997.
16.
AIS-023. Automotive vehicles-seats, their anchorages and head restraints for passenger vehicles of categories L7, M2, M3 and goods vehicles of category N-specifications. Pune: Ministry of Road Transport & Highways Government of India, 2017.
17.
GB13057. The strength of seats and their anchorages of passenger vehicles. Beijing, China: General Administration of Quality Supervision, Inspection and Quarantine of the People’s Republic of China (AQSIQ) & Standardization Administration of the People’s Republic of China (SAC), 2014.
18.
GB24406. The strength of student seat systems and their anchorages of special school bus. Beijing China: General Administration of Quality Supervision, Inspection and Quarantine of the People’s Republic of China (AQSIQ) & Standardization Administration of the People’s Republic of China (SAC), 2012.
19.
ElhamSKuroshDMohamadP, et al. Reducing occupant injury in frontal crashes for a low-floor city bus. In: ASME 2005 international mechanical engineering congress and exposition, Orlando, FL, USA, 5–11 November 2005, paper no. IMECE2005-83113, pp.113–120. New York, NY: ASME.
20.
LuisMAntonioGEnriqueA, et al. Child frontal impact safety in coaches. In: 22nd international technical conference on the enhanced safety of vehicles (ESV), Washington DC, USA, 12–16 June 2011, paper no.11-0383, pp.1–13. Washington DC, USA: National Highway Traffic Safety Administration.
21.
LuisMTeresaVAntonioG, et al. Analysis of coaches rows seats distance influence on the passengers comfort and safety. In: Proceedings of the 21st (ESV) international technical conference in the enhanced safety of vehicles, Stuttgart, Germany, June 2009, paper no.09-0197, pp.1–14. Washington DC, USA: National Highway Traffic Safety Administration.
22.
LiZGeHZhangJ, et al. The necessity of evaluating child neck injury in frontal collision of school bus for transportation safety. Saf Sci2014; 62: 441–449.
23.
LiZLiRZhangH, et al. Development of a school bus restraint system model and its application in the evaluation of designed protective strategies on child neck injury in front-end crash. Int J Crashworthiness2022; 27: 847–856.
24.
PengQSunTZhuP, et al. The influence of coach interior partitions and seat leaf-tables on occupant injury in a frontal collision. Int J Crashworthiness2022; 27: 337–346.
25.
PengQSunTZhuP, et al. Occupant injury risk assessment and protective measures in frontal collision of a bus. Int J Crashworthiness2019; 24: 429–441.
26.
ZhangJFangQWuL, et al. Optimization design for crashworthiness of special school bus seat based on simplified parametric model. Proc IMechE, Part D: J Automobile Engineering2018; 232: 1454–1464.
27.
KuznetcovATelichevI.Influence of non-standard seating postures on safety of motorcoach passengers in frontal collisions: a numerical study. Saf Sci2019; 113: 1–8.
28.
KuznetcovATelichevI.Effect of acceleration pulse shape on the safety of unbelted motorcoach passengers in frontal collision under uncertainty of their seating posture. Int J Crashworthiness2020; 25: 231–241.
29.
ProchowskiLDębowskiAŻuchowskiA, et al. Evaluation of the influence of velocity on dynamic passenger loads during a frontal minibus impact against an obstacle. In: Scientific conference on automotive vehicles and combustion engines (KONMOT 2016), Krakow, Poland, 22–23 September 2016, vol. 148, pp.1–10. England: IOP Conference Series: Materials Science and Engineering.
30.
JorlövSBohmanKLarssonA. Seating positions and activities in highly automated cars-a qualitative study of future automated driving scenarios. In: Proceedings of the IRCOBI conference on the biomechanics of impacts, Antwerp, Belgium, 13–15 September 2017, pp.1–10. Zurich, Switzerland: International Research Council on Biomechanics of Injury (IRCOBI).
31.
AlbertssonPFalkmerT.School bus–related injuries among children and teenagers in the United States, 2001-2003. Accid Anal Prev2005; 37: 225–233.
32.
BjörnstigJAlbertssonPBylundP, et al. Injury events among bus occupants-not just high speed and mass casualty situations. IATSS Res2005; 29: 79–87.
33.
McGeehanJAnnestJVajaniM, et al. Is there a pattern in European bus and coach incidents? A literature analysis with special focus on injury causation and injury mechanisms, 2001-2003. Pediatrics2006; 118: 1978–1984.
34.
United Nations Economic Commission for Europe (UNECE) Regulation No. 94 (ECE R94). Uniform provisions concerning the approval of vehicles with regard to the protection of the occupants in the event of a frontal collision. United Nations Economic Commission for Europe (UNECE), 1995.
UenoKMelvinJW.Finite element model study of head impact based on hybrid III head acceleration: the effects of rotational and translational acceleration. J Biomech Eng1995; 117: 319–328.
38.
GablerLFCrandallJRPanzerMB.Assessment of kinematic brain injury metrics for predicting strain responses in diverse automotive impact conditions. Ann Biomed Eng2016; 44: 3705–3718.
39.
TakhountsEGCraigMJMoorhouseK, et al. Development of brain injury criteria (BrIC). Stapp Car Crash J2013; 57: 243–266.
40.
GablerLFCrandallJRPanzerMB.Development of a metric for predicting brain strain responses using Head kinematics. Ann Biomed Eng2018; 46: 972–985.
41.
GablerLFCrandallJRPanzerMB.Investigating brain injury tolerance in the sagittal plane using a finite element model of the human head. Int J Automot Eng2016; 7: 37–43.
42.
KleivenS. Influence of direction and duration of impacts to the human head evaluated using the finite element method. In: 2005 International IRCOBI conference on the biomechanics of impact, Prague, Czech Republic, 21 September 2005, pp.41–57. Pennsylvania, USA: SAE.
43.
KleivenS.Evaluation of head injury criteria using a finite element model validated against experiments on localized brain motion, intracerebral acceleration, and intracranial pressure. Int J Crashworthiness2006; 11: 65–79.
44.
KleivenS.Predictors for traumatic brain injuries evaluated through accident reconstructions. Stapp Car Crash Journal2007; 51: 81–114.
45.
KelarRHasijaVTakhoutsE. Effect of angular acceleration on brain injury metric. In: IRCOBI conference proceedings, Munich, Germany, 2020, paper no. IRC-20-65, pp.552–568.
46.
SunMSCaiXYLiuQ, et al. Application of simulation methods in cervical spine dynamics. J Healthc Eng2020; 2020: 7289648–7289712.
47.
MalikAARobinsonSKhanWS, et al. Assessment of range of movement, pain and disability following a Whiplash Injury. Open Orthop J2017; 11: 541–545.
EliasJSullivanLMcCrayL.Large school bus safety restraint evaluation- phase II. In: Proceedings of 18th international technical conference on the enhanced safety of vehicles, Nagoya, Japan, 19–22 May 2003, pp.1–11. Washington DC, USA: National Highway Traffic Safety Administration.
50.
YounG.Neck injuries in low speed frontal collisions. Int J Veh Des2003; 32: 84.
51.
PanjabiMWangJDelsonN. Neck injury criterion based on intervertebral motions and its evaluation using an instrumented neck dummy. In: International research council on the biomechanics of injury conference, Sitges, Spain, September 1999, vol. 27, pp.179–190. Zurich, Switzerland: IRCOBI.
52.
SmotrovaEMorrisLMcNallyD.Comparison of standard automotive industry injury predictors and actual injury sustained during significant whiplash events. Eur Spine J2021; 30: 3043–3058.
53.
IvancicPCShaD.Comparison of the whiplash injury criteria. Accid Anal Prev2010; 42: 56–63.
54.
PanjabiMMItoSIvancicPC, et al. Evaluation of the intervertebral neck injury criterion using simulated rear impacts. J Biomech2005; 38: 1694–1701.
55.
GermanettiFFiumarellaDBelingardiG, et al. Injury criteria for vehicle safety assessment: a review with a focus using human body models. Vehicles2022; 4: 1080–1095.
56.
RuanJEl-JawahriRChaiL, et al. Prediction and analysis of human thoracic impact responses and injuries in cadaver impacts using a full human body finite element model. Stapp Car Crash J2003; 47: 299–321.
57.
XiaoSMoFYangJ, et al. The influence of impact speed on chest injury outcome in whole body frontal sled impacts. Transport2021; 35: 669–678.
58.
YuichiKTsuyoshiY. Correlation among seatbelt load, chest deflection, rib fracture and internal organ strain in frontal collisions with human body finite element models. In: 2013 IRCOBI conference proceedings, Gothenburg, Sweden, 11–13 September 2013, pp.282–316.
59.
DiggesKDalmotasDPrasadP. Application of multiple rib gages to improve chest injury measurements. In: Proceedings of the 26th ESV conference, Eindhoven, The Netherlands, 10–13 June 2019. Washington DC, USA: ESV.
60.
XiaoSShiXSunX, et al. Impact overlaps on occupant lower limb injuries under car frontal crash. Int J Autom Technol2022; 23: 659–665.
61.
XiaoSChenWLiuX, et al. An influence study of active muscle and sitting postures on lower limb injuries during frontal impact. Int J Crashworthiness2022; 27: 857–867.
62.
JiPZhouQ.Influence of school bus seat spacing on crash protection of six-year olds. Int J Veh Saf2015; 8: 115.
63.
PatilCPatilR.Design & analysis for strength of school bus seat to avoid the failure. IATSS Int J Res Publ Eng Technol2017; 3: 22–25.
64.
TangYWangTXiaoG, et al. 3D impact modeling and analysis of rear-seat structure for a minibus frontal crash. Asian J Appl Sci Eng2018; 29: 213–220.
65.
KristinBJackson LawrenceJBarbaraC.Simulations of large school bus crashes. SAE Int2000; 109: 645–658.
66.
PáezJFuronesAAparicioF, et al. Spanish frontal accidents of buses & coaches. Injury mechanism analysis. Procedia Soc Behav Sci2014; 160: 314–322.
67.
GB7258-2017. Technical specifications for safety of power-driven vehicles operating on roads. Beijing, China: General Administration of Quality Supervision, Inspection and Quarantine of the People’s Republic of China (AQSIQ) & Standardization Administration of the People’s Republic of China (SAC), 2017.
68.
GeRLuZZhaoF. Research of front seat design parameters on rear seat passenger safety. In: 2013 international conference on quality, reliability, risk, maintenance, and safety engineering (QR2MSE), Chengdu, China, 15–18 July 2013, pp.520–523. New York, NY: IEEE.
69.
DurbinDRJermakianJSKallanMJ, et al. Rear seat safety: variation in protection by occupant, crash and vehicle characteristics. Accid Anal Prev2015; 80: 185–192.
70.
Federal Motor Vehicle Safety Standards (FMVSS) No. 222 (FMVSS 222). School bus passenger seating and crash protection. Washington DC: National Highway Traffic Safety Administration (NHTSA), 2011.
71.
ZhangXChenC. A study of occupant injury based on dynamic test of a school bus seat. In: 2013 fifth international conference on measuring technology and mechatronics automation, Hong Kong, China, 16–17 January 2013, pp.94–97. New York, NY: IEEE.
72.
GB24407. The safety technique specifications of special school. Beijing, China: General Administration of Quality Supervision, Inspection and Quarantine of the People’s Republic of China (AQSIQ) & Standardization Administration of the People’s Republic of China (SAC), 2012.
73.
DuGEJTanWWangZ. Improvement on crash worthiness of steel energy absorbing structures in coach-to-car frontal impact. Int J Simul Syst Sci Technol2016; 17: 6–6.
74.
ShánělVŠpanielM. Composite absorber in collision simulations of a bus. J Middle Eur Construct Des Cars2017; 15(1): 1–5.
75.
AcarEYilmazBGülerMA, et al. Multi-fidelity crashworthiness optimization of a bus bumper system under frontal impact. J Braz Soc Mech Sci Eng2020; 42: 493.
76.
JongpradistPSaingamNTangthamsathitP, et al. Crashworthiness analysis and design of a sandwich composite electric bus structure under full frontal impact. Heliyon2022; 8: e11999.
77.
DeulgaonkarVRKulkarniMSKhedkarSS, et al. Crash analysis of bus body structure using finite element analysis. Int J Veh Struct Syst2020; 12: 312–316.
78.
BaaskaranNShankarSPalanisamyN, et al. Augmentation of crashworthiness design of circular tubular structures by engraving grooves of varying depths. Mech Adv Mater Struct2023; 30: 3097–3110.
79.
JongpradistPSenawatSNuangtoB. Improvement of crashworthiness of bus structure under frontal impact. In: The 2015 world congress on advances in structural engineering and mechanics (ASEM15), Incheon, Korea, 25–29 August 2015, pp.1–11. Daejeon, Korea: ASEM.
80.
United Nations Economic Commission for Europe (UNECE) Regulation No.29. Uniform provisions concerning the approval of vehicles with regard to the protection of the occupants of the cab of a commercial vehicle. Geneva: United Nations Economic Commission for Europe (UNECE), 1958.
81.
AndresGAngelMJavierP.Analysis of the driver’s workplace in coaches related to passive safety. Int J Veh Des2006; 42: 134.
