Seluga 1 ANALYSIS AND PREVENTION OF CHILD EJECTIONS FROM GOLF CARS AND PERSONAL TRANSPORT VEHICLES

United States Consumer Products Safety Commission statistics indicate there are approximately 13,000 golf car related emergency room visits in the United States annually. Of these, approximately 40% involve children (i.e. age < 16) and 50% of these involve a fall from a moving car. Evidence also indicates that many passenger ejections occur during left turns. Children are especially susceptible to ejection because of their small size and reliance upon the hip restraint for stability. While adult ejections have been studied, the present study analyzes mechanisms of child ejection during left turns. Dynamic tests are presented wherein an anthropomorphic Hybrid III 6 year old dummy in the front passenger seat is ejected during a moderate left turn and ejection kinematics are analyzed. An Articulated Total Body (ATB) occupant simulation is also presented, which compares favorably with experimental results. Additional simulations are presented wherein a seatbelt is found to be effective in preventing ejection with minimal belt force requirements. While experimental and simulated occupant dummies do not include muscular reactions, the potentially rapid onset of vehicle acceleration indicates that real occupants, particularly young children, may not have time to react before the ejection process has begun. Results indicate that current hip restraints are not large enough to prevent the ejection of small children during a moderate left turn. Additionally, seatbelts or straps are effective in preventing ejection during driver induced accelerations. The small belt force requirements indicate that seatbelts designed for use in automobiles and meeting Federal Motor Vehicle Safety Standards (FMVSS) may not be necessary. Based on these results, it is recommended that children be prohibited from riding in golf cars without a seatbelt type restraint when driven on golf courses and that seatbelt type restraints be provided for each occupant, especially children, when driving outside the golf course setting. INTRODUCTION Research and data compiled across the country indicate that the use of golf cars and Personal Transport Vehicles (PTVs) is rapidly expanding, as are the numbers or injuries related to their use. Recent research conducted by the University of Alabama at Birmingham [1] has indicated that about 1,000 Americans are injured in golf car related accidents each month. Another study completed by the Center for Injury Research and Policy at Nationwide Children’s hospital in Columbus, Ohio [2] stated that annual injury rates for golf cars increased 130 percent over 16 years ending in 2006. This study suggested that rules should be in place banning children under 6 years old from riding in golf cars. These studies and their underlying data also indicate that passenger ejection is a dominant mode of injury in golf car and PTV accidents, especially when children are involved. The testing and simulations in the present study investigate the effectiveness and load requirements for preventing ejection of children seated in golf cars. In addition to golf cars operated on golf courses, resort and retirement communities in the United States, as well as other local municipalities, now allow golf cars and Personal Transport Vehicles (PTVs) on streets as primary means of local transportation [3, 4, 5, 6]. In fact, local transportation of passengers is the express purpose of PTVs. Advertising for many PTVs produced by the major manufacturers (i.e. Club Car, E-Z-Go and Yamaha) specifically indicates that these vehicles are intended for “playing golf or cruising your neighborhood” [7] and “hauling kids” [8] and feature photos of young children riding in the vehicles. In response to the trend of using golf cars and PTVs off the golf course, 1 While the term ‘‘golf cart’’ is used by general public, the manufacturers of those vehicles use the term ‘‘golf car.’’ Seluga 2 the U.S. National Highway Traffic Safety Administration implemented requirements for safety equipment on Low Speed Vehicles (LSVs) that operate on public roads including mandatory seatbelts for all passengers [9, 10, 11]. However, these regulations define a Low Speed Vehicle as one having a top speed between 32 and 40 kph (20 and 25 mph). As a result, vehicles with top speeds below 32 kph (20 mph), such as golf cars and PTVs remain unregulated. Golf cars and Personal Transport Vehicles are often substantially similar, are manufactured by the same group of companies, and are virtually indistinguishable to the common observer. However, the manufacturers differentiate these vehicles based on maximum speed and intended usage, which can lead to confusing or ambiguous distinctions. For the purposes of this study, it is sufficient to understand that according to American National Standards Institute (ANSI) standards, the term “golf car” applies to vehicles with a top speed of less than 15 mph that are “specifically intended for and used on golf courses for transporting golfers and their equipment” [12] while “Personal Transport Vehicle” (PTV) applies to vehicles with a top speed of less than 20 mph which are “operated on designated roadways, or within a closed community where permitted by law or by regulatory authority rules” not including golf cars [13]. Previous research performed by Seluga et al [14] and Long et al [15] has demonstrated the ineffectiveness of most hip or handhold restraint systems typically found on existing golf cars and PTVs. In fact, it has been demonstrated that these types of restraints can exacerbate the problem by acting as a tripping mechanism, increasing the likelihood that an ejected occupant will strike the ground head first. Additionally, the documented increase in golf car and PTV injuries is consistent with the data presented by Long et al [15], which indicated an increase in the number of injuries due to increased vehicle usage and the lack of any seatbelt requirements. This study also demonstrated the effectiveness of seatbelts in preventing passenger ejections. Thus, if seatbelts were provided and users exhibited comparable compliance rates to those for automobiles (i.e. approximately 80% [16,17]), then approximately 80% of ejection accidents could be prevented by providing seatbelts. The debate concerning restraint systems on golf cars and PTVs has had opposing opinions both for and against seatbelts. The opinion that golf cars and PTVs should not have any type of seatbelt system has been primarily put forth by the National Golf Car Manufacturers Association (NGCMA), a non-profit corporation consisting exclusively of golf car manufacturers and organized “to promote the common business interest of its members” [18]. During the 1997 NHTSA rulemaking process related to the newly designated motor vehicle category of “Low Speed Vehicle” (LSV) [9], the NGCMA viewed the seatbelt requirement as “antithetical to the personal safety of drivers and occupants of golf cars” [10] and cited ANSI/NGCMA Z 130.1-1993 [19] which required a Rollover Protective Structure (ROPS) for any golf car containing seatbelts. Additionally, the NGCMA suggested that existing hip restraints do not prevent occupants from jumping or leaping out of golf cars to avoid injury when the car is about to rollover. Accordingly, the NGCMA Golf Course Safety Guidelines [20] state that “use of seatbelts without adequate overhead protection may result in severe injury or death.” The investigation by NHTSA regarding the establishment of the “Low Speed Vehicle” (LSV) classification included research of golf car safety; until it was determined that NHTSA would only regulate Low Speed Vehicles intended for on-road use and with a minimum speed of 20 mph. Hence golf cars and PTVs with a maximum speed of less than 20 mph are not currently regulated by any federal agency and the decision to require seatbelts in golf cars and PTVs is left to state and local jurisdictions. It should also be noted that NHTSA in its final ruling concluded that “the conjecture by some commenters that it would be valuable to be able to jump out of an LSV are unsubstantiated speculation that is especially unpersuasive given the volume of data showing that ejection is extremely dangerous and that seatbelts are remarkably effective at preventing ejection” [10].