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SAE paper 2013-01-0213 [1] described firefighting tests with Li-Ion traction batteries. However, additional knowledge and experience has been gained since then. In 2018 and 2019, DEKRA Accident Research and the Department of Anesthesiology of the University Medical Center Göttingen conducted crash tests far beyond standard with four battery electric vehicles. Three of the vehicles’ batteries were used to test a new method of firefighting. A specially designed lance was used to pierce the battery housing, which enabled water to be directly fed into the housings themselves. The method proved to be very effective, but the tests also showed some limitations. The information gleaned from this series of tests and experience gained from other tests was used as a basis for the formation of a multidisciplinary group of experts.

The number of full electric and hybrid electric vehicles is rapidly growing [1][2][3]. The new technologies accompanying this trend are increasingly becoming a focal point of interest for rescue services. There is much uncertainty about the right techniques to free trapped occupants after an accident. The same applies to vehicle fires. Can car fires involving vehicles with a lithium ion traction battery be handled in the same way as conventional vehicle fires? Is water the right extinguishing agent? Is there a risk of explosion? There are many unanswered questions surrounding the topic of electric vehicle safety. The lack of information is a breeding ground for rumours, misinformation and superficial knowledge. Discussions on various internet platforms further this trend. Tests were conducted on three lithium ion traction batteries, which were fuel-fired until burning on their own. The batteries were then extinguished with water, a surfactant and a gelling agent.

The number of vehicles equipped with automatic emergency braking systems is rising. Today most high-end auto makers offer pre-crash systems with a sensor-based collision warning feature. These systems warn the driver both audibly and visually when their sensors detect an imminent crash. Depending on system range, the occupants are moved into an optimized position, seat belts are pretensioned and the brakes are prepared for faster or, if necessary, maximum deceleration. A key feature of these systems is their ability to provide autonomous partial to full emergency braking in critical situations, thereby reducing collision speeds. Until now, crash tests have failed to mirror accident situations in which vehicles are braked prior to impact. Thus, it has not been possible to test the effectiveness of pre-crash occupant positioning or to reproducibly analyze the benefits of occupant preconditioning by pre-crash systems.

Further developments in automotive engineering and design contribute to vehicle safety. The increasing complexity of the systems complicates repair work. Faulty repairs can not only lead to malfunctions of the vehicle or components but also to vehicle fires. This paper presents some example cases of fire investigations directed at determining targeting to find out, whether the repair caused the fire or if other causes led to the ignition.

A changed attitude to environmental concerns together with rising fuel prices has resulted in an increasing demand for alternative forms of fuel for vehicle propulsion. In particular, the registration figures for vehicles powered with compressed natural gas (CNG) and liquefied petroleum gas (LPG) show strong growth rates in Europe. Both vehicles originally equipped by the manufacturer and those which are retrofitted are very common. To find out more about the technical- and fire safety of retrofitted cars DEKRA Accident Research carried out a crash test in accordance with FMVSS 301. The results were used to prepare a guide for rescue services.

The demands made on motor vehicles have risen enormously over the past few years. These demands that have led the automotive engineers to develop entirely new concepts for safety, comfort, reliability and environmental compatibility. These changes have resulted in completely new vehicles which pose additional hazards to rescue service personnel in the case of a severe incident. DEKRA Accident Research analysed several vehicle fires to find out more about typical and specific risks. The paper sets out the dangers which exist, how the fire services can react to them and where improvements are required or possible.

A decreasing supply of oil necessitates alternatives in powering vehicles to ensure mobility for future times. Hydrogen, natural gas and methanol are three of the most discussed replacements for common fuel. Even though some of these alternative concepts are still based on conventional internal combustion engines the fuel storage and supply systems contain a lot of differences. The question about the fire safety is one of the first asked in all cases the fuel system is affected. Various regulations ensure a high safety level but differences to conventional systems stay.

Although post-collision vehicle fires occur in less than 1% of all traffic accidents, they pose an enormous threat to the passengers involved. According to an estimate made by the German Federal Highway Research Institute about 80 persons are killed by post-collision vehicle fires each year in Germany, while the NHTSA refers to about 300 in the USA. To learn more about what causes the fires and to thus be able to conclude prevention measures, DEKRA analysed 79 accidents involving a vehicle fire. The consequent report identifies the main causes of ignition and the combustibles most frequently involved. Rudimentary proposals for improvements are outlined and relevant legal regulations are listed.