What Is Flame?
The flame resistance test evaluates whether vehicle materials ignite when directly exposed to flame, how far the flame spreads, and whether they self-extinguish once the flame source is withdrawn. Unlike the horizontal burn-rate test, the vertical orientation and melting-material behaviour can also be addressed.
Purpose of Flame
The purpose is to limit the material's contribution to flame spread in a fire, and to preserve evacuation time, especially in passenger-carrying vehicles.
Which Products Is Flame Applied To?
- Bus and minibus interior-trim materials
- Seat fabric and foam
- Ceiling and wall linings
- Insulation materials
- Cable insulation and protective conduits
In Which Sectors Is Flame Used?
Standards Related to Flame
- UNECE R118combustion behavior of internal materials test
- ISO 3795
- FMVSS 302
- ISO 6940
- ISO 6941
Flame Conditions
- Specimen orientation
- Horizontal or vertical, according to the applied annex
- Flame application
- Burner type, flame length and application time prescribed by the standard
- Conditioning
- Holding in the standard atmosphere before the test
Equipment for Flame
- Burn test chamber (horizontal and vertical rig)
- Standard gas burner
- Specimen holders
- Stopwatch and measuring ruler
- Dripping-assessment rig (cotton pad)
- Conditioning chamber
Sample Requirements for Flame
- Specimens of the dimensions prescribed by the standard
- Generally at least five specimens
- Layer structure and orientation must be preserved in composite material
- The material's location of use in the vehicle must be stated
Duration of Flame
Conditioning takes at least 24 hours; the test itself takes a few minutes per specimen.
Flame Procedure
- 1Samples are cut and conditioned according to the standard.
- 2The specimen is placed in the holder at the relevant orientation.
- 3The burner flame is applied for the defined duration.
- 4The flame is withdrawn and the specimen's behaviour is observed.
- 5Flame-spread distance and time are measured.
- 6Self-extinguishment time is recorded.
- 7Melting drip and the ignition effect of the dripping material are evaluated.
Flame Acceptance Criteria
The acceptance criterion is determined by the requirements of the applied annex: criteria such as the horizontal burn-rate limit, flame-spread distance and extinguishment time in the vertical test, and the dripping material not igniting the cotton beneath it, are defined in the standard's text.
Evaluation of Results
Each specimen is evaluated separately and the worst-case result is used. Dripping behaviour is as significant a finding as flame spread; dripping melt can ignite underlying layers and accelerate the fire.
Flame Report
- Applied standard and annex
- Specimen description, thickness and construction
- Conditioning conditions
- Flame-application conditions
- Spread, duration and extinguishment results for each specimen
- Dripping observations
Accreditation
EUROLAB holds internationally recognised accreditation obtained from accreditation bodies party to the IAF and ILAC multilateral recognition arrangements, under ISO/IEC 17025 for laboratory testing, ISO/IEC 17020 for inspection and surveillance, and ISO/IEC 17021-1 and ISO/IEC 17065 for system and product certification. This chain ensures the reports and certificates issued are accepted worldwide.
Whether this test can be offered within accredited scope depends on your product and the standard applied; since accreditation is method-based, the scope is confirmed in writing at the quotation stage.
Scope and authorisationsRelated Regulations
- UNECE R118
- Vehicle type-approval legislation
Otomotiv Testleri — What Does This Testing Field Cover?
The section below describes the field that the Flame test belongs to; the conditions and acceptance criteria of this particular test are given in the sections above. The scope specific to your product is confirmed in writing at the quotation stage.
Automotive testing shows that a component keeps working under conditions representing the loads it will meet over the life of the vehicle. A vehicle is not a single product but an ENVIRONMENT: vibration, temperature cycling, salt water, stone impact, electrical transients and electromagnetic noise are all present at the same time and for years.
What distinguishes this family is that VEHICLE MANUFACTURER SPECIFICATIONS sit on top of the standards. ISO and SAE publications establish the common ground; but Volkswagen, BMW, Ford, Stellantis, Toyota and Renault define different severity levels, additional tests and different acceptance criteria in their own specifications. For a component, the phrase "complies with automotive standards" is not sufficient on its own; which manufacturer's specification, and which revision of it, must be answered.
The family carries three separate processes together and they are often confused. Homologation covers the type approvals a vehicle needs to enter traffic and runs under state authority. Supplier approval means passing the vehicle manufacturer's own quality and testing requirements and is a commercial relationship. The third is design verification: the engineering team demonstrating that its own design meets its targets.
At component level the test plan is built around the LOCATION OF USE. A module in the engine bay and a module in the boot do not go through the same temperature and vibration profile; a component inside a door and one in the roof console do not see the same water and dust exposure. The ISO 16750 series is the common framework for this location-based approach.
The shift to electric vehicles has reshaped the field. High-voltage safety, insulation coordination, battery safety, charging interface conformity and the electromagnetic behaviour of high-voltage components have been added to the classical automotive test set. In a quiet vehicle, acoustic and vibration expectations have changed too; sounds once masked by the combustion engine are now audible.
The quality system side cannot be separated from testing in this field. A manufacturer under IATF 16949 presents test results in the PPAP file; measurement system analysis, process capability study and the control plan stand around the test report. A single good result is not enough — the process must be shown to be able to repeat it.
Method groups in this field
Environmental and climatic
Temperature cycling, thermal shock, damp heat, salt spray, dust and water ingress (IP), solar radiation. Severity levels vary with the mounting location.
Mechanical
Sine and random vibration, shock, mechanical loads, fastener torque and durability cycles.
Electrical
Supply voltage variations, transients (ISO 7637), reverse polarity, overvoltage, short circuit and sleep current measurements.
EMC
Component emissions (CISPR 25), radiated and conducted immunity (ISO 11452 series), electrostatic discharge (ISO 10605).
Materials and emissions
Odour, fogging and VOC emissions from interior materials; flammability; UV ageing; coating durability and stone impact.
Functional safety and cyber security
Functional safety evidence under ISO 26262 and cyber security engineering under ISO/SAE 21434; these are tied to regulation through UNECE R155 and R156.
Commonly confused in this field
- An automotive report without a specification reference is not accepted in the supply chain; which OEM specification and revision was applied must be stated.
- Type approval and supplier approval are different processes. A component with E-Mark approval is not thereby considered to have passed the OEM's own acceptance tests.
- A result obtained on a prototype does not carry over to series production; PPAP is done with series production parts.
- On the EMC side, measuring emissions alone is incomplete; immunity is a separate body of work and is more critical in a vehicle.
- On electric vehicle components, high-voltage safety is a distinct competence; classical 12 V test infrastructure is not sufficient.
Which decisions these results support
- Supplier component approval and the PPAP file
- UNECE type approval and E-Mark marking
- Design verification and durability evidence
- Root cause analysis of field complaints and warranty returns
- Assessing the impact of a design or supplier change
Related Tests
Frequently Asked Questions About Flame
What do R118's annexes cover?
R118 contains several test annexes: horizontal burn rate, vertical burning behaviour, behaviour of melting materials, and insulation materials' resistance to fuel/lubricant droplets, among others. Which annexes apply is determined by the material's location in the vehicle.