NFPA 701

Standard Methods of Fire Tests for Flame Propagation of Textiles and Films

Understanding NFPA 701 and the Role of Flame Propagation Testing

NFPA 701 is a recognised fire-test standard developed by the National Fire Protection Association to examine how textile and flexible materials respond when exposed to a direct ignition source. Rather than modelling a complex or prolonged fire event, the standard concentrates on a material’s basic fire behaviour — whether it supports flame spread or limits it.

This makes NFPA 701 particularly useful for evaluating fabrics used in environments where uncontrolled flame growth would present a serious safety concern. By focusing on ignition response and flame behaviour at the material level, the standard provides a consistent reference point for determining whether a textile is suitable for use in regulated, public-facing, or safety-critical applications.

How Fire Cloak™ Meets NFPA 701

Fire Cloak™ EV fire blankets have undergone independent laboratory testing to confirm that the materials used in their construction align with the expectations of the NFPA 701 standard. These assessments verify that the blanket fabric does not readily sustain combustion and demonstrates controlled behaviour when subjected to an ignition source.

For EV fire containment, this distinction is important. During lithium-ion battery incidents, materials positioned close to the vehicle must not introduce additional fire load or promote flame growth at a critical stage of the response. Demonstrating compliance with NFPA 701 helps confirm that Fire Cloak™ is manufactured using textiles specifically selected to perform reliably in high-temperature environments, supporting safer containment and reducing the risk of escalation during an incident.

NFPA Test Reports

NFPA Test Report (4x3m)NFPA Test Report (4x3m)
Specimen NumberResidual Flame (seconds)Weight Loss (%)
10.02.29
20.02.44
30.02.23
40.02.19
50.03.60
60.02.45
70.02.26
80.04.81
90.02.37
100.02.64
AVG0.02.63

NFPA Test Report (8x6m)NFPA Test Report (8x6m)
Specimen NumberResidual Flame (seconds)Weight Loss (%)
10.00.45
20.00.55
30.00.61
40.00.71
50.00.57
60.00.54
70.00.54
80.00.55
90.00.58
100.00.63
AVG0.00.57

NFPA Test Report (12x9m)NFPA Test Report (12x9m)
Specimen NumberResidual Flame (seconds)Weight Loss (%)
10.01.39
20.01.20
30.01.34
40.01.43
50.01.32
60.01.70
70.01.65
80.01.70
90.01.15
100.01.43
AVG0.01.43

What This Means in Practice

NFPA 701 is not designed to recreate the extreme conditions of a lithium-ion battery fire, but it does provide a recognised way to evaluate how textile materials behave when exposed to an ignition source and whether flame spread is effectively controlled.

Strong performance against the principles assessed by NFPA 701 indicates that a fabric is resistant to sustained ignition and does not readily contribute additional fuel to a fire. For EV fire-containment blankets, this behaviour is critical — helping to limit flame propagation, support containment efforts, and reduce escalation risks during an incident.

Below is what this means for different decision-makers and operational teams.

Material compliance with NFPA 701 provides a clear, independently recognised reference point when assessing flame-resistant textiles. It offers procurement teams documented assurance that the product is manufactured using materials suitable for safety-critical applications, supporting internal approval processes, supplier validation, and compliance reporting when specifying EV fire-response equipment.

For technical and safety teams, NFPA 701 performance is an indicator of controlled flame behaviour and material stability under direct ignition. Materials that resist flame propagation and self-limit combustion are better suited to environments where ignition sources, elevated temperatures, and fire exposure risks are present. This helps inform engineering decisions, site risk assessments, and the selection of containment solutions for workshops, charging areas, test facilities, and operational depots.

Operational crews require equipment that will not introduce additional hazards during deployment. A containment blanket manufactured from materials that demonstrate controlled flame response helps ensure there is no unexpected flame spread when managing an EV fire incident. NFPA 701 compliance supports confidence that the blanket will maintain its integrity during use, providing responders with greater stability and control in time-critical scenarios.

In locations such as depots, car parks, logistics hubs, and charging installations, fire-containment equipment must be capable of performing safely under incidental flame exposure. Materials assessed against NFPA 701 criteria offer reassurance that the blanket is constructed from textiles that resist ignition and do not exacerbate fire conditions — an important consideration where vehicles, infrastructure, and personnel are in close proximity.

From a risk and liability perspective, reference to NFPA 701 testing provides independent evidence of material flame behaviour. Demonstrating that fire-containment equipment uses textiles designed to control flame spread supports broader mitigation strategies and shows a proactive approach to managing lithium-ion fire risks. This can assist with risk assessments, insurance discussions, and compliance documentation.

Certified Proof & Next Steps

Fire Cloak™ compliance with NFPA 701 is supported by formal, independent laboratory testing carried out on multiple blanket sizes. Each configuration was assessed individually to confirm that the materials used in Fire Cloak™ EV Blankets demonstrate controlled flame behaviour when exposed to an ignition source, in line with the principles evaluated by the standard.

The results show that the specialist fabrics used in Fire Cloak™ are resistant to sustained combustion and do not contribute to flame propagation when subjected to controlled flame exposure. This behaviour is a critical requirement for materials intended for fire-containment applications, where preventing secondary ignition and limiting flame growth are essential to managing lithium-ion battery incidents safely.

While NFPA 701 does not attempt to replicate the full scale or intensity of an EV battery fire, these independently verified test outcomes provide clear, objective evidence of material suitability. Combined with real-world deployment, operational testing, and ongoing collaboration with industry stakeholders, they give organisations confidence that Fire Cloak™ is built on a robust, independently assessed foundation of fire-performance credibility.

Fire Cloak™ Lithium Battery Fire Limitation Blanket (4 x 3m)

Fire Cloak™ EV Fire Limitation Blanket (8 x 6m)

Fire Cloak™ XL – EV Fire Limitation Blanket (12 x 9m)

About NFPA 701

NFPA 701 is a widely referenced fire-test standard used to evaluate the flame-propagation behaviour of textile and flexible materials when exposed to an ignition source. Developed for use across public, commercial, and safety-critical environments, it is commonly applied to fabrics where controlling flame spread is essential, rather than simulating a full-scale fire scenario.

For Fire Cloak™, NFPA 701 provides an established benchmark for assessing the flame-response characteristics of the materials used in its construction. It offers independent confirmation that those materials are resistant to sustained ignition and do not readily contribute to flame growth — supporting the suitability of Fire Cloak™ EV Blankets for use in high-risk, fire-response applications.

NFPA 701 is a fire-test standard published by the National Fire Protection Association and is used to evaluate the flame-propagation characteristics of textiles and flexible materials when exposed to an ignition source. The standard is commonly referenced for fabrics used in public, commercial, and safety-critical environments where controlling flame spread is essential.

Rather than focusing on a specific end-use scenario, NFPA 701 provides a consistent framework for assessing whether a material is inherently flame resistant and whether it limits the growth and spread of fire once ignition occurs. For this reason, it is widely applied to products such as curtains, drapes, decorative fabrics, films, and technical textiles where fire performance must be demonstrated independently of full-scale fire conditions.

In the context of EV fire-containment solutions, NFPA 701 is used to assess the behaviour of the blanket’s base materials under controlled flame exposure. This helps determine whether those materials are suitable for use in environments where ignition sources, elevated temperatures, and secondary fire risks may be present — without attempting to replicate the full severity of a lithium-ion battery fire.

NFPA 701 is designed to assess how a textile material behaves once ignition occurs, with a particular focus on whether flame spread is controlled or self-limiting. Instead of attempting to recreate a real-world fire scenario, the standard evaluates fundamental flame-response characteristics that help indicate whether a material is likely to contribute additional fuel to a fire.

At a high level, the standard is concerned with questions such as:

  • Does the material ignite readily when exposed to a flame?
  • Does combustion continue once the ignition source is removed?
  • Is flame propagation limited, or does the material support ongoing fire growth?

By addressing these principles, NFPA 701 provides a recognised reference point for determining whether a fabric demonstrates inherent flame resistance, rather than relying on coatings or treatments that may degrade over time or under heat exposure.

For EV fire blankets, this distinction is important. Materials that resist sustained ignition and limit flame propagation are less likely to exacerbate an incident during deployment, helping to support containment efforts and reduce secondary fire risks in high-temperature environments.

NFPA 701 includes two distinct test methods, each intended to assess flame behaviour under different material configurations and use cases. Rather than representing different performance levels, the methods exist to ensure that a wide range of textile types can be evaluated in a manner appropriate to their form and typical application.

At a conceptual level, the two methods are used to account for factors such as:

  • Material weight and construction
  • How the textile is typically installed or deployed
  • The way flame interaction may differ between lighter and heavier fabrics

Because of this, the choice of test method is determined by the characteristics of the material itself, not by the end product or industry in which it is used.

For fire-containment blankets used around electric vehicles, understanding that NFPA 701 incorporates multiple assessment approaches helps clarify how different blanket sizes and constructions can be evaluated consistently. While the test methods vary in setup, they share a common objective: confirming that the material demonstrates controlled flame behaviour and does not promote flame propagation when exposed to an ignition source.

Results from NFPA 701 testing are used to determine whether a textile material demonstrates controlled flame behaviour when exposed to an ignition source. Rather than producing a graded score or performance ranking, the standard is typically applied as a pass/fail reference, indicating whether the material meets the accepted expectations for limiting flame spread and sustained combustion.

In practical terms, a material that satisfies the intent of NFPA 701 is one that does not continue to burn excessively, does not promote ongoing flame growth, and does not significantly contribute additional fuel to a fire scenario. This makes the standard particularly useful as a baseline indicator of flame resistance for textiles intended for safety-critical or regulated environments.

For EV fire blankets, NFPA 701 results are interpreted as evidence that the underlying fabric is suitable for use in situations where ignition sources and elevated temperatures may be present. While the standard does not measure containment capability or thermal endurance during a lithium-ion battery fire, it does help confirm that the blanket’s materials will not exacerbate an incident through uncontrolled flame propagation during deployment or use.

NFPA 701 is intended to assess material-level flame behaviour under controlled conditions. It is not designed to replicate the complexity, duration, or intensity of a real-world fire scenario, and it does not attempt to model how a product will perform in a fully developed fire.

In particular, NFPA 701 does not simulate:

  • The extreme temperatures generated during a lithium-ion battery thermal runaway
  • Prolonged heat exposure or sustained fire conditions
  • Pressure, jet flames, or explosive gas release
  • The dynamic behaviour of a live EV fire incident

Instead, the standard provides a focused evaluation of whether a textile material contributes to flame spread once ignition has occurred. This makes it valuable as a screening and suitability test for fabrics used in environments where ignition risk exists, but it should always be interpreted as part of a wider fire-safety and risk-management strategy.

For EV fire blankets, NFPA 701 is therefore best understood as one element within a broader evidence base. It confirms that the blanket’s materials are resistant to uncontrolled flame propagation, but it does not, on its own, define containment performance, suppression capability, or overall incident outcome during a lithium-ion battery fire.

Electric vehicle fires present a unique challenge, combining high heat output, unpredictable flame behaviour, and the risk of secondary ignition from surrounding vehicles, infrastructure, or materials. In these conditions, the performance of a fire-containment blanket is influenced not only by its size and deployment method, but also by the behaviour of the materials from which it is made.

NFPA 701 matters because it helps establish whether those materials are likely to contribute to or control flame spread when exposed to an ignition source. A containment blanket that resists sustained ignition and limits flame propagation is less likely to exacerbate an incident during deployment, repositioning, or prolonged use around a burning vehicle.

For EV fire blankets, compliance with NFPA 701 supports confidence that the textile construction is suitable for high-risk environments where ignition sources and elevated temperatures may be present. While the standard does not assess containment duration or thermal endurance during a lithium-ion battery fire, it provides valuable assurance that the blanket’s materials will not introduce additional fire hazards at a critical moment.

In practice, this makes NFPA 701 a meaningful part of a broader performance picture — complementing real-world deployment experience, operational testing, and other material assessments that together inform safe and effective EV fire response planning.

The complete NFPA 701 standard is published and maintained by the National Fire Protection Association and should be consulted directly for full technical requirements, test procedures, and official guidance.

For more information and expert advice,
drop us a message.

Get in touch

Fire Cloak™
14-16 Gleadless Road
Sheffield
S2 3AB
UK

T: +44 (0)114 255 7700
F: +44 (0)114 255 7171
E: sales@firecloak.co.uk