EV Fire Blankets: What They Can and Cannot Do

DVM International | Technical Insights

Understanding the role, capabilities and limitations of fire limitation blankets in electric vehicle fire safety.

Electric vehicles present particular challenges for fire safety, especially when lithium-ion traction batteries are involved. Fire services, vehicle recovery companies, parking operators and safety professionals are therefore paying increasing attention to large vehicle fire blankets. But what can these blankets actually achieve?

The essential distinction is simple: an EV fire limitation blanket is designed to limit the effects and spread of a fire. It is not a guarantee that a lithium-ion battery fire will be extinguished.

1. What Is an EV Fire Limitation Blanket?

An EV fire limitation blanket is a large, heat-resistant textile cover intended to provide temporary fire limitation around a vehicle. Unlike a conventional household fire blanket, it is designed for vehicle-scale use and demanding thermal and mechanical conditions.

The original German DIN SPEC 91489:2024-11 describes the purpose as the spatial and temporary limitation of fire spread associated with electric vehicles and their traction batteries. It also makes clear that these blankets are not active extinguishing agents. The subsequent DIN 91489-1:2026-11 provides an updated standard for evaluating this product category.

This is why DVM International uses the term Fire Limitation Blanket (FLB) rather than suggesting that the blanket alone extinguishes a battery fire.

Explore the DVM 6 × 8 m EV Fire Limitation Blanket, developed for professional applications.

2. Why Thermal Runaway Changes the Situation

A lithium-ion battery cell may enter thermal runaway when damage, overheating or another critical condition triggers self-accelerating heat-producing reactions. Heat and flammable gases can be released, and the process may spread to neighbouring cells or modules.

Restricting oxygen can reduce flames outside the battery pack, but it does not necessarily stop reactions inside the cells. Suppressing visible flames and stabilising a traction battery are different objectives. A vehicle may also present a risk of delayed reignition after flames appear to have subsided.

3. What Can an EV Fire Blanket Do?

Limit external flames

By restricting the supply of atmospheric oxygen, a suitably designed blanket may reduce or suppress visible flames outside the battery. Its actual effect depends on the fire conditions, coverage and deployment.

Help limit fire spread

A fire limitation blanket is intended to reduce the spread of fire and associated heat exposure to the surroundings. The extent of this benefit must be supported by relevant testing and assessed for the intended scenario.

Support professional incident management

Possible applications include vehicle recovery operations, controlled quarantine areas and other locations where a damaged or potentially hazardous vehicle must be managed. Deployment should form part of a broader incident plan and be undertaken by appropriately trained personnel.

4. What Can an EV Fire Blanket Not Do?

These limitations do not automatically make the equipment ineffective. They establish the boundaries within which its potential benefits must be evaluated.

5. What Does Independent Research Tell Us?

Research by the Fire Safety Research Institute (FSRI), part of UL Research Institutes, has highlighted an important distinction between visible flame suppression and control of the underlying battery incident.

FSRI has warned that flammable battery gases may accumulate beneath a deployed blanket and, in some circumstances, create a deflagration hazard. Its full-scale EV fire research also examined blanket deployment and the use of water. These findings deserve careful consideration, especially during active battery involvement and in confined or poorly ventilated environments.

There has also been disagreement about how particular test scenarios and deployment methods should be interpreted. For example, some blanket manufacturers have questioned the representativeness of certain experimental procedures. Such comments should be considered as manufacturer perspectives, not as grounds for dismissing observed hazards.

The appropriate conclusion is neither that EV blankets are universally safe nor that they have no useful role. Their suitability depends on the incident, deployment method, trained responders and independently demonstrated performance.

Why water still matters

FSRI's research reinforces the continuing importance of water in EV firefighting. A blanket may limit external flaming, while water remains important for controlling the vehicle fire, cooling accessible components and protecting nearby exposures.

Water cannot be assumed to stop thermal runaway inside a battery pack, particularly where its construction prevents effective cooling. Nor does the research mean that water should automatically be directed beneath every deployed blanket: tactics must reflect the incident conditions and the hazards identified by the responding fire service.

Is water safe around high-voltage batteries?

Trained firefighters can generally use water on EV fires while following established electrical safety procedures. Vehicle high-voltage systems are normally designed to be electrically isolated from the chassis, but electric shock risks cannot be dismissed, particularly where battery housings, cables or charging equipment are damaged or energised.

Responders must follow the relevant emergency response guidance, maintain appropriate separation from exposed electrical components and use suitable protective equipment. A fire limitation blanket itself provides no protection against electric shock.

6. Why Technical Standards and Testing Matter

DIN SPEC 91489:2024-11 established technical requirements for EV fire limitation blankets, including thermal resistance, mechanical strength, handling, storage, markings and manufacturer information. The later DIN 91489-1:2026-11 updates this framework.

One important change is the material fire-classification requirement: the earlier specification called for at least class B with d0, whereas the newer standard specifies A2-s1,d0 for the relevant coated or laminated textile construction. Other changes concern test methods, product requirements and documentation.

A claimed maximum fabric temperature is not proof that an entire blanket meets the standard. Seams, handling loops, material construction, dimensions, deployment and the prescribed thermal and mechanical tests all matter.

For that reason, buyers should distinguish between material data, individual laboratory test results and verified conformity of a finished product.

See the DVM-FLB-6×8 product specifications for the current product information and testing status.

7. What Should Professional Buyers Look For?

Beyond advertised heat resistance, a responsible evaluation should consider:

• Intended use: vehicle types, incident scenarios and operating environment.
• Coverage: sufficient dimensions to cover the vehicle and provide the required ground overlap.
• Construction: textile material, coatings, seams and handling components.
• Independent evidence: laboratory identity, standard edition, test conditions, results and limitations.
• Deployment: trained operators, handling time and practical access.
• Documentation: inspection, storage, service life, cleaning, disposal and warnings.

A transparent test report is more useful than broad promises of guaranteed extinguishment or unrestricted high-temperature performance.

8. The DVM International Approach

DVM International is developing the DVM-FLB-6×8, a 6 × 8 metre Fire Limitation Blanket intended for professional EV applications. The product is subject to an independent testing programme with SGS.

Until the final results have been reviewed, design specifications and material characteristics should not be presented as proof of finished-product compliance with DIN 91489-1:2026-11. We intend to update this article and the product documentation as verified results become available.

Our guiding principle is straightforward: fire safety claims should be supported by transparent, independently verifiable evidence.

Conclusion

EV fire limitation blankets may have a valuable role in professional fire safety, but they are not stand-alone solutions to lithium-ion battery thermal runaway. They can help limit some external effects of a fire while important hazards—including gas accumulation, electrical risks and reignition—remain.

Water-based firefighting, appropriate training, incident-specific procedures and independently tested equipment remain essential. The right question is not simply whether a blanket can suppress flames, but what it has been shown to achieve, under which conditions and with which limitations.

References and Further Reading

1. DIN SPEC 91489:2024-11, Requirements for fire limitation blankets for use with electric vehicles, DIN Media.
2. DIN 91489-1:2026-11, current German standard for EV fire limitation blankets, DIN Media.
3. Fire Safety Research Institute (FSRI), Potential Hazard Involving EV Fire Blankets.
4. Fire Safety Research Institute (FSRI), Full-Scale Electric Vehicle Fire Experiments and Recommendations for Fire Incident Response.
5. Bridgehill, Manufacturer commentary on EV fire blanket testing methods (industry perspective).

Technical information is provided for professional awareness and does not replace incident-specific risk assessment, emergency response procedures or the manufacturer's instructions. Product conformity claims will be updated when independent test evidence is available.