Analytical Overview of Accident Emergencies Arising from the Structure and Characteristics of Various Alternative Fuel Vehicles ^†

Abstract

The spread of alternative fuel vehicles (AFVs) poses new technological and legal challenges. While these vehicles contribute to sustainable transport, their specific operational characteristics require specific regulation and infrastructure. The study analyses the risks associated with AFVs, in particular with regard to occupational safety and operation, and the extent to which the current legal framework in Hungary is able to address these challenges. It also examines the integration of AFVs into the existing transport and service network and makes recommendations for improving regulation, training and infrastructure. The study aims to contribute to enhancing road safety and legal clarity by showing that the safe integration of AFVs requires the modernisation of regulation and the adaptation of technical protocols.

1. Introduction

Alternative fuel vehicles (AFVs) are spreading rapidly worldwide: according to the Hungarian Central Statistical Office, the number of electric, hybrid and other vehicles has been growing intensively every year, especially since 2020 [1]. The emergence and spread of electric, hybrid, hydrogen and other alternative fuel vehicles makes it critical to identify operational risks and safety implications and to prepare for emergency situations. This calls for solutions from legislators and transport infrastructure managers and developers. The aim of the study is to map the legal regulation of alternative fuel vehicles, with particular emphasis on occupational safety regulations and the areas of service and operation. A number of questions arise in connection with new technologies: how existing regulations can be adapted to innovative types of vehicles, and what health and safety aspects need to be taken into account during maintenance and operation. The study not only presents the existing national and European legislation, but also focuses on some of the challenges of practical application.

2. Interpreting Emergency Situations from the Perspectives of Innovation Optimism and Innovation Scepticism

Societal perceptions of new technologies (including automotive novelties) are often at two extremes: on the one hand, there is so-called “technological optimism” and on the other, “technological scepticism”.

Technological optimism inherently describes the belief that technological progress is shaping the world in a positive direction: it can solve environmental, economic and social problems. It sees technology as a driver of progress through human ingenuity and innovation, which also improves well-being, health and quality of life. From the Industrial Revolution onwards, optimistic narratives have often accompanied technological achievements, and in the 20th and 21st centuries they have been reinforced in the context of the digital revolution and the information society [2,3]. Technological scepticism, on the other hand, is a view that is critical of technological progress, pointing out its risks and side effects. This view emphasises that technologies are not neutral but embedded in power structures, often creating new problems while trying to solve old ones. The sceptical view is that technological progress does not guarantee automatic social progress—especially if it is not accompanied by adequate ethical, legal and social control [4]. As a result, the two schools of thought not only judge different technological tools differently, but also have fundamentally different views on the role of technology in society: while optimism sees it as an opportunity, scepticism sees it as a threat and an uncontrolled force. In contemporary philosophy of technology, both perspectives play an important role, especially in relation to complex phenomena such as artificial intelligence or the field of automotive technology (autonomous vehicles, alternative fuel systems).

The so-called risk society theory, as described by Ulrich Beck, brought about a fundamental shift in the sociological understanding of the relationship between modernity and technology. According to Beck, a specific feature of advanced industrial societies is that they not only produce goods and wealth, but also generate new types of global and often invisible risks as a ‘by-product’—such as environmental pollution, climate change, nuclear accidents or the unpredictability of technological systems. They are not evenly distributed and their social interpretation is strongly dependent on trust: the degree to which society has confidence in the developers, operators, and regulators of technology [5,6]. This is particularly relevant for alternative fuel vehicles, where society values not only the usefulness of new technologies, but also their safety, transparency, and regulation. An accident (e.g., battery explosion or fire) can be not only a specific technological failure but also a catalyst for a loss of confidence. The spread of alternative fuel vehicles is itself a reflexive response to the risks associated with fossil energy (e.g., air pollution, climate change), but it also generates new risks that have yet to be addressed by society. Modern risks are often not directly perceived but need to be mediated by science, further complicating the issue of societal trust and responsibility.

The following Figure 1 clearly illustrates the most common types of dangerous situations caused by alternative fuel vehicles:

Figure 1. Types of Hazards in Alternative Fuel Vehicles.

The maintenance, repair and operation of electric, hybrid, hydrogen and other alternative fuel vehicles present specific hazards, and the requirements for conventional internal combustion engines may not be an appropriate solution. This is an opportunity to try to map the relevant legislation and, in the spirit of technological optimism, to point out its strengths or, in the context of technological scepticism, to draw attention to the need for improvements. First of all, what new types of threat should we expect? One of the most critical hazards is fire, which can arise from traditional causes, but also from new technologies: chain reaction combustion due to battery failure, fire during charging, explosion, LPG vehicles with leaking gas bursting into flames, fire during alternative fuel storage, use of inadequate insulation techniques, etc.—the list is obviously not exhaustive, it is almost impossible to list the many possible hazards [7,8]. The health and safety of persons in contact with such vehicles (firefighters and rescue workers, operators, etc.) is therefore of paramount importance, and both EU and national legislation seek to ensure this through strict rules.

3. Health and Safety Rules for AFVs

The relevance of OHS legislation is that technical solutions other than conventional vehicles require special training, appropriate personal protective equipment and a special working environment. As new types of vehicle become more widespread, there is a need to modernise health and safety standards to ensure the safety of workers.

The European Union Member States’ occupational safety and health legislation is in line with Directive 89/391/EEC. In Hungary, occupational safety and health regulations are laid down in Act XCIII of 1993 on Occupational Safety and Health (hereinafter: the Mvt.), the general provisions of which are mandatory for all employers: the employer must carry out a risk assessment and determine the necessary protective measures against all sources of danger. The risk assessment must include a qualitative and, if necessary, quantitative assessment of the risks to the health and safety of workers, in particular the work equipment used, hazardous substances, the stresses to which workers are exposed and the design of workplaces. In the risk assessment, the employer identifies the expected hazards and the persons at risk and estimates the degree of exposure according to the nature of the hazard [see Section 54 (3) of Mvt.].

According to the Mvt., a sufficient number of workers with appropriate professional qualifications must be available to carry out the work safely and without endangering health. Work must not be carried out alone where there is a risk of danger, and only workers who have received appropriate training (see Section 55 of the Mvt.) may enter such places. Work may pose a risk to the physical integrity or health of the worker, and the Minister responsible for employment policy may, in agreement with the Minister responsible for health and the Minister responsible for the activity, stipulate that it may only be carried out by a person with specific qualifications (training) or experience [see Section 51 (1–3) of the Mvt.].

Employers must also ensure that workers receive appropriate training and education on safe work requirements. The preparation of the training syllabus is an occupational safety and health activity [see Section 55 (1, 3) of the Mvt.]. The employer is also expected to provide the necessary personal protective equipment (e.g., depending on the specific hazard, this may include protective clothing, insulating gloves, face shields, respiratory protection, etc.). The employer must define in writing the internal arrangements for the provision of personal protective equipment and ensure that workers use it as intended [see Section 56 of the Mvt.].

Workers working with alternative fuel vehicles must also have the appropriate qualifications for the specific tasks. The practical implementation of occupational safety is facilitated by the need to provide special training for mechanics (as required by the general rules of the Mvt.). Practice shows that there are significant training gaps to be filled, for which vocational training, micro-certification and specialist engineer training could be quick and competent solutions. For example, training courses for “hybrid and electric vehicle mechanics” are also available in Hungary (e.g., the Budapest Chamber of Commerce and Industry launched such training in 2021), which provide participants with the specificities of high-voltage technology and safety requirements. In Europe, it is common to require the use of specialised personnel in these fields, who undergo standardised training. In Germany, the industry accident insurance organisation (DGUV) has issued a specific directive requiring all self-employed mechanics working on high-voltage vehicles to undergo at least one basic training course in electrical engineering lasting several weeks. This has become practically mandatory: since 2020, only workshops in Germany that have a “Hochvolttechniker” (High Voltage Technician) trained in high voltage systems are allowed to work on high voltage vehicles. Under German rules, this person follows strict safety rules, uses special insulated tools and protective equipment to avoid accidents, and regularly attends training and exams to keep up to date with the latest technologies and regulations [9]. In 2023, an important piece of legislation was introduced in Hungary: the GFM Decree 21/2023 (VIII.30.), which introduced a new system of electrical apprenticeships. It specifically mentions the qualification “FAM mechanic of traction battery for motor vehicles” and sets out the rules for working under voltage. This step also provides a legal framework to ensure that only qualified professionals can work on EV batteries in the future.

It is also important to mention that, in practice, vehicle manufacturers issue detailed installation instructions for the safe disconnection of high-voltage systems (service connectors, use of service disconnect, disconnection of 12 V systems, etc.). In Hungarian law, there is a special regulation on working under voltage on electrical equipment, GFM Decree 21/2023 (VIII.30.).

The main focus of occupational health and safety in the case of vehicles powered by automotive gas is also fire and explosion protection. LPG can form an explosive mixture with air and is heavier than air, so it can build up on the floor level in enclosed, unventilated spaces. CNG is lighter than air and rises upwards, but can also be dangerous in confined spaces. In line with health and safety regulations, these technologies must be chosen so that hazardous substances do not cause health hazards. Accordingly, continuous ventilation and an environment free of ignition sources must be ensured when working on gas-powered vehicles [10]. Workshops must comply with the so-called ATEX standards (national equivalents of Directive 1999/92/EC and the Equipment Directive 94/9/EC for explosive atmospheres). In Hungary, the National Fire Safety Regulations of the Ministry of the Interior Decree 54/2014 (XII.5.) (hereinafter: OTSZ) also contains provisions:, e.g., from a fire safety point of view, gas-powered vehicles may only be stored or repaired in a closed space if ventilation is provided and the vehicle’s gas system is properly installed. The OTSZ states that purely or partially gas-fuelled vehicles may not be stored in basements or enclosed unventilated spaces unless the vehicle’s gas installation is approved and the ventilation of the space is provided.

There is also a safety aspect behind this requirement: maintenance staff must know that such vehicles can only be lifted into the workshop under safe conditions. General fire safety rules must also be observed during work: welding and hot work on gas-powered vehicles must be carried out only after the tank has been degassed, and extinguishers and supervision must be provided. It is advisable for mechanics to wear antistatic work clothing as personal protective equipment (to prevent sparks from forming) and skin protection is also important in the case of LPG, as contact with the liquid–gas can cause frostbite. A gas detection device is also a typical personal protective equipment: the work area should be constantly monitored for leaks of gas at dangerous concentrations [11]. These requirements derive partly from the general provisions of the Mvt. (handling of dangerous substances) and partly from sector-specific rules. In Hungary, for example, NGM Decree 2/2016 (5 January 2016) deals with the safety of pressure equipment and filling stations and states that filling equipment for automotive gas may only be operated if it is properly authorised; this indirectly protects the workers who fill the equipment.

As for the occupational health and safety challenges of hydrogen vehicles, although there are still few hydrogen vehicles (fuel cell vehicles) in use, the legal environment is trying to prepare for this. Hydrogen is a highly flammable gas and forms an explosive mixture with air. It is also colourless, odourless and leaks easily due to its very small molecule. The occupational safety requirements for hydrogen filling stations and repair workshops are also defined by ATEX and fire safety regulations. In workshops where hydrogen vehicles are repaired, continuous gas detection (hydrogen detection sensors), ventilation and a strict ban on the use of open flames are mandatory. Hydrogen fuel cell cars can have tanks with a pressure of up to 700 bar; mechanical damage to these can be a serious source of accidents. Therefore, the rules for pressure vessels (e.g., periodic inspection) also apply to hydrogen tanks [12]. At EU level, minimum requirements are laid down in the framework of occupational health and safety regulations for work with dangerous substances (e.g., Directive 1999/92/EC, already mentioned). For work involving hydrogen vehicles, the employer should lay down procedures (e.g., how to carry out a leakage test, what protective clothing is required, what to do in the event of an emergency, etc.) in a separate health and safety policy.

4. Special Requirements for Service and Operation

Multiple specialised statutory instruments govern the inspection, repair, and maintenance—as well as the day-to-day operation—of vehicles equipped with alternative powertrains, thereby ensuring their safe performance throughout the entire life-cycle.

In the context of maintenance and repair (servicing), the Hungarian legislator stipulates that only licenced undertakings may carry out vehicle maintenance (vehicle repair) activities. Such undertakings must comply with the precise conditions, both personal and material, laid down by law. This is particularly true for the servicing of alternative fuel vehicles, where a specific licence or qualification is often required for certain operations. In the case of LPG and CNG vehicles, Regulation (EC) No 2/2004 requires that the repair and maintenance of the gas fuel system may only be carried out by a qualified vehicle maintenance organisation designated for this purpose. In practice, this means that the gas injectors, reducers and tanks of an LPG car, for example, can only be fitted by a service company that is licenced by the transport authority to do so and that has a specialised gas safety certificate. After the repair, the gas fuelled equipment must be tested for tightness and a certificate issued. NGM Decree No. 2/2016 (5 January 2016) stipulates that LPG tanks must be inspected (certified) for technical safety or replaced every 10 years—this task can also only be carried out by an authorised service company. The fact of the inspection is certified on the tank data plate or by a separate certificate; in the absence of such a certificate, the vehicle may not be put into service. CNG tanks are usually specified by the manufacturer as having a service life of 20 years; in Hungarian practice, the validity of the tank is checked during the roadworthiness test and if it has expired, it needs to be replaced. The most important thing to remember when servicing electric/hybrid vehicles is that work on high voltage systems, as mentioned in the health and safety section, should only be carried out by qualified personnel. The internal instructions of the service workshops typically require that before high voltage work is carried out, the vehicle must be marked, the 12 V battery disconnected and the high voltage battery disconnected from the vehicle’s mains. In Hungarian law, there is no specific law or regulation that requires, for example, the qualification to replace the battery pack—this is regulated by market practice through branded services.

Regulation 2018/858/EU, which has already been referred to several times, also covers the availability of repair and maintenance information: vehicle manufacturers must provide independent repairers with the necessary repair instructions and diagnostic protocols, including specific information for alternative fuel vehicles. This means that, for example, the fault codes and repair procedure for a high-voltage battery in an electric car can be retrieved by independent repairers via the manufacturer’s online systems—the law seeks to reduce the safety risks of a monopoly by ensuring that all qualified repairers have access to the information.

During operation, the owner/operator of the vehicle must ensure that the vehicle complies with the continuous operating conditions. The legislation enforces this through a system of periodic roadworthiness tests. There are also additional checkpoints in the periodic testing of alternative fuel vehicles compared to normal cars. In the case of electric vehicles, for example, the integrity of the insulation of the high-voltage cables, the operation of the emergency switch (if fitted), the fixing of the battery and the condition of any warning lights (insulation fault indicators) are checked. In the case of hybrid vehicles, a check is made that both drive modes are operational and that the emission control system (OBD, catalytic converter) is in good working order [13]. For gas vehicles, a gas safety certificate not more than 30 days old, issued by an authorised service centre after the vehicle has been inspected, etc., will be presented at the test. A similar procedure is expected for hydrogen vehicles: e.g., periodic inspection of the tanks will be coordinated with the technical inspection of the vehicle. For hydrogen vehicles currently in the experimental stage, the registration licence will be issued on a case-by-case basis and the authority may oblige the owner to carry out certain extra checks (e.g., annual compaction test at a designated workshop) [14].

It is worth mentioning some operating restrictions and special rules. There are also some specific rules for the use of alternative fuel vehicles, mainly to ensure safe operation. One example is the OTSZ parking requirement: gas-powered cars can only be stored in underground garages if the vehicle’s gas tank and equipment are certified and the appropriate warning sign is displayed in the garage. The regulation also specifies the exact wording of the prohibition sign [“No entry for LPG vehicles without safety valve”, see Section 220 (5) of the OTSZ], meaning that it is mainly cars that have not been properly modified that are prohibited. This also shows that the legislation seeks to exclude unlicensed, potentially dangerous vehicles from risky situations.

Since 2019, the use of an Acoustic Warning and Acoustic Alert System (AVAS) has been mandatory at EU level for electric vehicles: newly type-approved electric and hybrid cars must be equipped with an audible warning system that emits a continuous audible warning at low speeds (usually between 0 and 20 km/h) to protect pedestrians. This requirement is laid down in Regulation (EU) No 540/2014 and its amendments. A further operational specificity is that the charging and refuelling process is also regulated: electric cars may only be charged in public areas at designated charging points and charging equipment must comply with the requirements of Directive 2014/94/EU and those implemented through the Hungarian legislation (e.g., standardised plug, contact protection, MID certified accounting). When refuelling with LPG fuel, it is a requirement to stop the vehicle’s engine and evacuate passengers—this is more of a technological instruction, but the legal basis is in the safety regulations for refuelling stations. Other EU Member States also have operating restrictions: in Austria, for example, CNG buses are banned from certain tunnels for fire safety reasons; in Germany, local regulations in environmental zones determine that green badge (low emission) vehicles can enter—including electric and hydrogen cars automatically, while old LPG cars can be banned if they do not meet Euro standards. These examples show that the rules for the operation of alternative fuel vehicles are constantly evolving, both at national and international level, in line with the spread of the technology and experience [15].

5. Proposals

Above all, the legal framework needs to be refined to reduce the risks of natural disasters. The next amendment to the OTSZ should require the installation of heat and smoke detectors in garages for electric vehicles and more stringent fire resistance requirements for structures based on lithium-ion fire tests. Damaged but not yet ignited high-voltage batteries should be immersed in water or placed in a heat-resistant container before transport. A national “rescue data sheet” system should be set up to provide immediate information to emergency services on the accident vehicle when calling 112. The updated European (CEN/CENELEC) standards should be introduced as soon as possible as national standards and enforced in inspections, while operators should also be obliged to draw up and agree with the local fire brigade their own emergency plans for fires caused by electric vehicles.

Training represents the second pillar of safety enhancement. Both initial and continuing firefighter education should incorporate additional hands-on and virtual-reality modules, allowing personnel to rehearse interventions involving alternatively powered vehicles without incurring risk. For emergency medical services, a concise, targeted course ought to demonstrate how to isolate the vehicle’s electrical supply before casualties are treated. Although the new high-voltage systems are already addressed in automotive-technician programmes, this content must also be extended to charging-station personnel. Finally, public information campaigns—using infographics, media features, and similar outlets—can provide continuous reminders of the fundamentals of safe home charging and the appropriate post-accident procedures.

Infrastructure development is likewise critical. With state support, fire-service agencies should acquire specialised equipment such as immersion containers, piercing-nozzle extinguishers, high-capacity mobile ventilators, and thermal imaging cameras. In municipalities operating large fleets of electric buses or trolleybuses, the installation of underground fire-water reservoirs adjacent to depots is advisable. Car-park operators ought to be incentivised—through tax concessions, for example—to install sprinkler or water-mist systems, gas- and smoke-detection sensors, and floor-by-floor fire compartmentation. High-power charging stations must be equipped with portable fire extinguishers, emergency shut-off controls, and camera surveillance, whereas enclosed LPG forecourts should employ automatic gas detectors to ensure the immediate recognition of leaks [16].

Finally, international collaboration and targeted research are essential to ensure that regulatory frameworks keep pace with technological advances. Hungary stands to gain from staging joint, V4-level simulated firefighting exercises, while simultaneously fostering industry-led innovation. The European Union’s new Battery Regulation (2023/1542) and the sheltered-parking guideline expected in 2025 already provide an appropriate legal scaffold; it is therefore incumbent upon national legislation and regulatory practice to translate these instruments into effective, on-the-ground implementation with the utmost dispatch.

Based on the above, it can be concluded and confirmed with the help of the Figure 2 below which entities are most affected by AFV security and to what extent:

Figure 2. Stakeholders involved in AFV safety.

6. Conclusions

The analysis demonstrates that, in step with the pace of technological advancement, the regulation of vehicles equipped with alternative fuel systems is receiving increasing attention in Hungary. Legislators and regulatory authorities must continually keep abreast of technical innovations to safeguard road-traffic safety and meet environmental-protection requirements. Experience gained between 2022 and 2025 confirms that, given adequate preparedness, the associated risks are manageable: they are neither more frequent nor inherently more intractable than the hazards posed by conventional vehicles. The key lies in readiness and responsiveness—up-to-date regulation, well-trained specialists, and infrastructure that not only facilitates the dissemination of new technologies but is also equipped to address the attendant emergency scenarios. It is in this spirit that the legal and practical measures of the coming years must be shaped, so that electric, hybrid, CNG, and LPG vehicles can be safely integrated into our transport system.