FAR PART 25 Appendix F Part I Vertical Horizontal 45° Multi-function Combustion Test Chamber

Product Introduce

The Multi-Function Burn Chamber, compliant with FAR Part 25 Appendix F Part I (a)(1)(2)(3), is a specialized fire testing apparatus designed to evaluate the flammability of aircraft interior and cargo compartment materials. It conducts vertical (12s/60s), horizontal, and 45-degree burn tests to measure flame spread, burn length, and self-extinguishing properties, ensuring compliance with FAA standards like FAR 25.853 and CS 25.853. Suitable for testing seat fabrics, carpets, wall panels, cargo liners, and electrical insulation, this stainless-steel chamber features precise flame control and automated timing. Its versatile configuration supports aviation safety certification, aligning with Airbus AITM 2.0002 and Boeing BSS 7230 standards.

Standard

I. Overview of FAR Part 25 Appendix F Part I (a)(1)(2)(3)

FAR Part 25 Appendix F Part I specifies the flammability test methods for aircraft interior materials and cargo compartment materials, mainly evaluating the behavior of materials in fire through combustion tests. These tests are usually conducted in a multi-functional combustion chamber to meet the test requirements at different angles (horizontal, vertical, 45 degrees, 60 degrees). The following are the key points of section (a)(1)(2)(3):

(a)(1) Vertical combustion test

12-second vertical combustion test: used to test the self-extinguishing properties of aircraft cabin and cargo compartment materials. The flame is applied for 12 seconds and then removed. The flame duration, dripping burning time and burnt length are recorded.

60-second vertical combustion test: more stringent requirements, the flame is applied for 60 seconds, mainly used in more critical parts (such as cabin materials).
Requirements: The sample size is 3 inches × 12 inches (75 mm × 305 mm), and the thickness does not exceed the actual use thickness. The test must be conducted in a windless environment with a flame temperature of at least 1550°F (843°C).

(a)(2) Horizontal burning test

Test content: The horizontal burning test is used to evaluate the flame propagation rate of the material after the flame is applied for 15 seconds. There are two rate

requirements:

(a)(2)(i): The flame propagation rate shall not exceed 2.5 inches/minute (64 mm/min).

(a)(2)(ii): The flame propagation rate shall not exceed 4.0 inches/minute (102 mm/min).

Requirements: The sample size is 3 inches × 12 inches, the thickness is consistent with actual use, and the average value of 3 samples is tested.

(a)(3) 45 degree burning test

Test content: For cargo hold lining or waste storage compartment materials, test flame penetration and flame duration. The flame is applied for 30 seconds, and the flame penetration, flame duration and afterglow time are recorded.

Requirements: The sample size is 10 inches × 10 inches (254 mm × 254 mm), the thickness does not exceed 1/8 inch (3.2 mm), and the flame must not penetrate the sample.

FAA related standards

14 CFR Part 25.853: Flammability requirements for aircraft interior materials, covering cabin and cargo hold materials.

14 CFR Part 25.855: Fire protection requirements for cargo hold and luggage hold materials, especially requiring 45-degree burning test.

FAA Aircraft Materials Fire Test Handbook (DOT/FAA/CT-99/15): Provides detailed test method guidance, including specific implementation steps for vertical, horizontal, 45-degree and 60-degree tests, and is a supplementary document to FAR Part 25 Appendix F.
Advisory Circular AC 25.853-1: Provides guidance on compliance testing for FAR 25.853 and clarifies the scope of application of vertical and horizontal burning tests.

European Aviation Safety Agency (EASA) Standards

CS 25.853: Equivalent to FAR 25.853, specifies the flammability requirements for large aircraft interior materials, and the test method refers to FAR Appendix F Part I.

CS 25.855: Cargo compartment material testing requirements, equivalent to FAR 25.855.

JAR 25.853: Joint Aviation requirements (now superseded by CS 25), test methods consistent with FAR.

Manufacturer and Industry Standards

Airbus AITM 2.0002A/B: Airbus vertical burn test (12 seconds and 60 seconds), consistent with FAR 25.853(a)(1).

Boeing BSS 7230 F1/F2: Boeing vertical and horizontal burn test standards, based on FAR Appendix F Part I.

ASTM E662: Smoke density test, used in conjunction with the FAR test to evaluate smoke generation when a material burns.

ISO 5659-2: Plastic smoke density test, related to the smoke analysis portion of the FAR test, can be extended to aviation materials testing.

Test product content

FAR Part 25 Appendix F Part I (a)(1)(2)(3) tests apply to various materials used in aircraft interiors and cargo holds. The specific product range includes:

Cabin interior materials

Seat materials: seat fabrics, foams, padding, flame retardant layers (if they meet FAR 25.853(a)(1)(i)/(ii)).

Carpet and floor materials: aviation carpets, floor coverings, laminate flooring.

Interior walls and ceilings: interior panels, dividers, decorative coverings.

Curtains and textiles: curtains, blackout fabrics, decorative fabrics.

Requirements: Must pass the 12-second or 60-second vertical burn test (a)(1), or the horizontal burn test (a)(2) to ensure self-extinguishing and low flame spread rate.

Cargo and baggage compartment materials

Lining materials: cargo compartment ceilings, side wall linings, floor materials.

Waste storage compartment materials: garbage containers, storage box linings.

Requirements: Must pass the 45-degree burn test (a)(3) to ensure that the flame does not penetrate the material, and the flame duration and afterglow time meet the standards.

Wire and cable

Insulation materials: Insulation and jacket materials of wires and cables.

Requirements: Must pass the 60-degree burn test (FAR Appendix F Part I (a)(7)), but combined with (a)(1)(2)(3) to ensure overall fire resistance.

Other components

Composites: Sandwich panels, fiberglass reinforced plastics.

Small components: Certain small components (such as knobs, handles, fasteners) may be exempt from testing, but if located in the cabin or cargo hold, they must

comply with (a)(1) or (a)(2).

Storage cabinets and galley structures: Cabinets, storage boxes, galley container exterior materials must pass horizontal or vertical tests.

Special materials

Thermal/acoustic insulation materials: Must be combined with FAR 25.856 Part VI testing, but the basic flammability test must still comply with Appendix F Part I.

Flexible and rigid pipes and connectors: The piping system inside the aircraft must pass vertical or horizontal flame tests.

Main parameters:

1. Working principle: The Bunsen burner in the combustion box is ignited through the automatic ignition device. After the machine sets the ignition time, the flame impacts the sample in the sample holder to determine whether the material is burning and the damage distance after burning.

2. Main structure: It includes the combustion test box host, gas control device, electrical control device, burner, horizontal combustion sample set, vertical combustion sample set, 45-degree combustion test set, 60-degree combustion test set, test weight, and temperature calibration unit.

3. The combustion test box can simultaneously meet the FAA vertical, horizontal, 45-degree and 60-degree combustion test modes;

4. The combustion test time is not less than 90s; the test time accuracy: 0.1s, the angle accuracy: 0.2 degrees

5. The pressure regulating device makes the methane outlet pressure 17±2kpa;

6. The Bunsen burner of the test box equipment can adjust the gas flow through the pressure reducing valve, pressure gauge and rotor flowmeter to obtain CCAR25 R4 The flame requirements specified in Appendix F1 adopt electric spark ignition, and the Bunsen burner can be controlled on the test box operation panel to ignite;

7. The burning test time is not less than 90s; the test time accuracy is 0.1s;

8. Afterburning time: not less than 90s, the test time accuracy is 0.1s

9. Dripping time: not less than 90s, the test time accuracy is 0.1s

10. After the burner is in place, the burning time is automatically triggered by the proximity switch, and the system can automatically record;

11. Bunsen burner test device, the inner diameter of the burner is 10mm or 3/8in, the flame height can be adjusted to 38±0.1mm, the temperature measured by the

thermocouple pyrometer at the center of the flame is >843 degrees, and the flame stability is ±5 degrees;

12. Equipped with a flame height gauge corresponding to the temperature of 843 degrees, the accuracy is not Less than 0.1mm, the outer flame and inner flame height can be measured simultaneously

13. In the 60-degree combustion mode, the flame height can be adjusted to 76.2±0.1mm, the temperature measured by the thermocouple pyrometer at the center of

the flame is >954 degrees, and the flame stability is ±5 degrees;

14. Equipped with a flame height gauge corresponding to a temperature of 954 degrees, the accuracy is not less than 0.1mm, and the outer flame and inner flame

height can be measured simultaneously;

15. Temperature calibration unit, including thermocouples and temperature display instruments, the thermocouple temperature resistance is not less than 1100 degrees, the diameter is 0.5mm±0.1mm, and the temperature display device displays an accuracy of ±0.1 degrees;

16. Vertical combustion sample clamp device: The vertical combustion sample clamp device consists of a bottom plate and a pressure plate, and the internal exposure (sample exposure) size is 52mm±1mm x356mm±1mm;

17. Horizontal combustion sample clamp device: The horizontal combustion sample clamp device consists of a bottom plate and a pressure plate. The burning rate scale lines are 292mm and 39mm. The sample exposure size is; 52mm±1mm x320mm±1mm;

18. 45 degree combustion sample clamp device: The 45 degree combustion sample clamp device consists of a bottom plate and a pressure plate. The sample exposure size is; 203mm±1mm x203mm±1mm;

19. The box is equipped with an exhaust device to help exhaust the smoke generated in the box to the outside of the box;

20. The test box is equipped with a large transparent observation window to monitor the test process;

21. The lighting device is installed inside the box to facilitate the user to observe the test process;

22. Equipped with methane gas bottles and gas installation cabinets, which contain methane gas detection devices and provide smoke exhaust pipes.

23. Methane is required to be a 40L steel cylinder with a purity of not less than 98%.

24. Environmental conditions

24.1 Ambient temperature requirement: 5-35℃

24.2 Humidity requirement: ≤90%RH

24.3 Air pressure requirement: 86KPa-106KPa

24.4 Electromagnetic environment: no strong electromagnetic radiation source nearby

25 Work site power configuration

25.1 Exhaust port: φ150mm;

25.2 Exhaust volume: 500 cubic meters/hour;

25.3 Power configuration: 220V, 50HZ, 0.5KW

26. Floor space

26.1Laboratory room: 1m*1m, tabletop installation

Packing list