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Vehicle seat belt efficacy relates directly to the extent that occupant anthropometric dimensions align with the seat belt geometric design. Transport Canada researched and developed a Belt Fit Test Device (BTD) to assess potential occupant injuries resulting from incongruities between seat belt design and occupant anatomical characteristics. A proposed electronic version (eBTD) will allow vehicle manufacturers to use digital human modeling programs and computer-aided design (CAD) data and tools to evaluate seat belt designs before a vehicle is produced. This software module simulates seat belt routing over CAD data representing the physical device. The simulation incorporates anchor point kinematics and measures the belt position over clavicle, sternum and lap scales.

In the fall of 2000, the Council of Ministers agreed that Canada should retain the vision of having the safest roads in the world, and that a longer term successor plan, called Road Safety Vision 2010, carry forward the work of Canada's inaugural national road safety plan. It was further agreed that the plan include an overall national target and sub-targets. A national target that calls for 30% decreases in the average number of road users killed and seriously injured during the 2008-2010 period below comparable 1996-2001 figures is currently under consideration. Achievement of this target would reduce Canada's road fatality total to fewer than 2100 by 2010.

The purpose of this project was to develop and validate a computer-based version of the Belt Fit Test Device with a view towards exploring the potential of this technology to improve belt fitment for the general occupant population. The electronic BTD was initially developed and validated against two seats using the Transport Canada seat simulator. Preliminary validation indicated good correspondence between computed and measured BTD co-ordinates. The electronic BTD was then validated in ten vehicles. In total, 40 BTD scores were computed using the electronic BTD and compared with actual BTD values. In 30 of the 40 comparisons, the discrepancy between measured and computed values was less than one centimetre. In terms of test performance using the pass/fail criteria developed for the BTD, 37 of the 40 comparisons were in agreement. However, a number of refinements have been identified which could further improve the seat belt algorithm and the overall usefulness of the model.

Correctly fitted seat belts save the lives of car passengers everyday. In attempt to reduce the risk of injuries, primarily abdominal, caused by inappropriate belt fitting, Transport Canada developed the Belt fit Test Device (BTD). The BTD is a physical hardware measuring device that tests whether the lap and torso belt are appropriately positioned with respect to the bony structures of the pelvis and rib cage of the restrained occupant. To overcome the deviations of hardware physical tests and to enable review of belt design in early design phases, the Alliance of Automobile Manufacturers funded the development of an electronic simulation and modeling tool in the form of an electronic Belt fit Test Device (eBTD). The development takes place in close co-operation with the Joint Working Group on Abdominal Injury Reduction (JWG-AIR).

The responses of a Hybrid III 5th percentile dummy manufactured by Denton ATD were compared to a Hybrid III 5th percentile dummy manufactured by First Technology Safety Systems (FTSS). The dummies were seated on a HYGE sled set in a representative small production sedan configuration, simulating a 60 km/h offset deformable barrier (25 g pulse) and a 22 km/h crash (11 g pulse). Three shoulder retractor anchorage positions were used to place the shoulder belt at different locations on the dummy shoulder for each of the driver (left shoulder) and passenger (right shoulder) seating positions. Chest deflections measured from the rotary potentiometer are compared to deflections calculated from the accelerometers and are reported as a function of belt load and belt position. Repeatability is evaluated at low and high deflection levels.

A study of vehicle accident data from insurance claim files was conducted to determine the relative effectiveness of red and amber turn-signal systems in reducing rear-end collisions. The effectiveness was measured in terms of the relative frequency of accidents involving these systems, with respect to a number of vehicle, environmental, and driver factors. Control for vehicle exposure was made by comparing the non-turning accidents with the turning accidents for the relevant rear-turn-signal systems. Analyses revealed that there were no statistically significant differences in rear-end accident rates between the red and amber turn-signal systems. On the basis of safety benefits, the results of the study did not appear to provide sufficient justification for changes to the present Motor Vehicle Safety Standards regarding the functional separation and colour coding of a rear-turn-signal system.

Drawing on provincial data files maintained by Transport Canada, the injury experience of passenger vehicle occupants as a function of occupant seating position, reported restraint use and occupant age is examined. Particular attention is given to the issue of rear seat lap belt effectiveness. Estimates of restraint system effectiveness are derived using a variety of approaches. These range from direct comparisons of the relative injury/fatality rates of restrained and unrestrained occupants in reportable accidents to double-pair comparisons based on “subject” and “control” occupants in fatal accidents. Available Canadian data suggest that the use of three-point seat belts by front seated occupants and the use of lap belts by rear seated occupants substantially reduces the likelihood of serious or fatal injury.

This paper provides details on the tests performed and the research findings of an underride guard test programme, including 10 full scale crashes using three types of deformable guards. The deformable guards tested included one meeting the minimum requirements of the NHTSA FMVSS 223 with ground clearances of either 560 or 480 mm, a second meeting the same minimum performance criteria with the addition of a device to limit the displacement of the horizontal member (ground clearance of 480 mm only) and a third being stiffer and designed to roughly maintain its 560 mm ground clearance during deformation. Crash tests were performed at speeds of 48, 56 and 65 kph.

Static out-of-position tests were performed to identify the potential for injury as a function of position, airbag type and vehicle seat characteristics. Seat and door mounted airbags, head curtains and head tubes were evaluated. Out-of-position testing was carried out with the Hybrid III 3 year old, 6 year old and the TNO Q3 3 year old child dummies. In-position tests and a dynamic test were conducted to monitor child seat and airbag interactions and to confirm that properly restrained children would not be exposed to undue risk from a deploying side airbag. Results of the out-of-position testing suggest that current side airbag designs may cause serious and/or fatal neck and chest injuries. In-position static testing with child seats suggested a potential for intrusion into the child occupant space leading to structural damage of the car seat.