FAR 25.853 Aircraft Flammability Guide
What Is FAR 25.853? Aircraft Cabin Flammability, Explained
The FAA's flammability rule for aircraft interior materials — what the paragraphs (a), (b), and (d) mean, the vertical-burn pass criteria, and how to find tapes tested to 25.853(a) by application.
FAR 25.853 (formally 14 CFR § 25.853, “Compartment interiors”) is the U.S. Federal Aviation Regulation that sets flammability requirements for the materials used inside transport-category aircraft cabins — panels, carpet, insulation, galley fittings, and the tapes that go with them. It is the regulation that sits underneath most of the Boeing, Airbus, and military specifications you'll see called out on a drawing. When a tape's data sheet says it “meets FAR 25.853(a),” it means the material was tested to the vertical Bunsen-burner criteria in Part I of Appendix F and passed.
See every FAR 25.853-tested tape we stock, grouped by spec.
View FAR 25.853 Tapes →What the FAR 25.853 paragraphs mean
A drawing or data sheet usually cites a specific paragraph of 25.853. Each one points to a different test in Appendix F. Here's how the common callouts break down:
Vertical burn test (Part I, Appendix F). The baseline requirement for interior materials regardless of aircraft size. This is the criterion most aerospace tapes are tested to.
Horizontal burn rate. Older paragraph references for less-critical materials, measured as a maximum burn rate rather than burn length.
Seat-cushion oil-burner test (Part II). A separate requirement for seat cushions — not typically relevant to tapes.
Heat release & smoke (Parts IV & V). Additional tests for large panels, partitions, and galley structure on aircraft seating 20 or more.
Related regulations. Cargo-compartment liners fall under FAR 25.855, and thermal/acoustic insulation under FAR 25.856. Products in our catalog are often qualified to several of these at once — for example, our cargo-pit tapes reference both 25.853(a) and 25.855(d).
FAR 25.853(a) vertical-burn pass criteria
The vertical Bunsen-burner test (Part I of Appendix F) is run in two versions — a 12-second flame application and a 60-second flame application — depending on the material and its location. A material passes only if the averaged results for all three test specimens stay within these limits:
| Criterion (averaged over specimens) | 60-second vertical test | 12-second vertical test |
|---|---|---|
| Maximum burn length | 6 in (152 mm) | 8 in (203 mm) |
| Maximum flame (self-extinguishing) time | 15 seconds | 15 seconds |
| Maximum drip extinguishing time | 3 seconds | 5 seconds |
For certain materials, a horizontal-burn version applies instead, with a maximum average burn rate of 2.5 in/min for 25.853(b-2) or 4 in/min for 25.853(b-3). The 60-second vertical test is the more stringent of the two vertical tests and is generally applied to larger interior surfaces; the 12-second test covers floor coverings, textiles, and many tapes. The specific test version required is set by the controlling drawing or material specification.
How tape qualification actually works. A roll of tape is not “FAR 25.853 certified” on its own. The FAA's procedure qualifies each type of tape on the surface it is applied to, so compliance is established for the tape-plus-substrate combination as installed. The right way to read a tape data sheet is that it has been tested to the 25.853(a) vertical-burn criteria with the typical burn values shown — always confirm the tape is qualified for your specific application and substrate.
Find a 25.853-tested tape by application
Most buyers arrive at FAR 25.853 from a specific job — securing carpet, sealing a cargo pit, splicing insulation. Here's how our flame-retardant tapes map to common cabin applications. Each is tested to the 25.853(a) vertical-burn criteria; see each product's data sheet for typical values.
| Application | Product | Also references |
|---|---|---|
| Cabin carpet / floor covering | Polyken 108FR carpet tape — see our BMS 5-133 guide | BMS 5-133; BAC 5034-4 |
| Cargo compartment liner / sidewall | Polyken 296FR cargo compartment tape — see our BMS 5-146 guide | BMS 5-146; 25.855(d) |
| Cargo-pit sealing (fiberglass) | Polyken 290FR cargo-pit sealing tape | FAR 25.855(d) |
| Cargo-pit duct / repair | Polyken 225FR cargo-pit duct tape | FAR 25.853(a)(1)(i) |
| Insulation blanket cover splicing | E&H 743-BLK, 770-3FRD & 770-3FRS — see our BMS 5-157 guide | BMS 5-157; 25.856(a); BSS-7230 |
| Galley / wet-seal | Patco 1800 galley tape | Fokker FK05-159/160 |
| Waterseal / moisture barrier | Patco D9100 waterseal tape — see our BMS 8-346 guide | BMS 8-346; ABS 5093 |
| Aluminum foil / speed tape | Polyken 345SW foil speed tape | AMS-T-23397B |
Need the data sheets? Typical burn-test values for each product are on its technical data sheet. Browse them all in our Technical Data Sheets library, or see the full spec cross-reference on our Specifications by Authority page.
Frequently asked questions
What is FAR 25.853?
FAR 25.853 (14 CFR § 25.853) is the U.S. Federal Aviation Regulation governing the flammability of materials used in transport-category aircraft cabin interiors. It defines the fire-test criteria — chiefly the vertical Bunsen-burner test in Part I of Appendix F — that interior materials and the tapes used with them must meet.
What does FAR 25.853(a) require?
Paragraph (a) requires interior materials to pass the vertical-burn test in Part I of Appendix F, regardless of the aircraft's passenger capacity. A material passes only if its averaged results stay within the burn-length, flame-time, and drip-time limits for the applicable 12- or 60-second test.
What are the FAR 25.853(a) vertical-burn pass criteria?
For the 60-second test: maximum 6-inch burn length, 15-second flame time, and 3-second drip extinguishing time. For the 12-second test: maximum 8-inch burn length, 15-second flame time, and 5-second drip extinguishing time. Results are averaged across three specimens.
Is a tape “FAR 25.853 certified”?
Not on its own. The FAA's procedure qualifies each type of tape on the specific surface it is applied to, so compliance is for the tape-plus-substrate combination as installed. A tape data sheet shows the typical burn values from testing to the 25.853(a) criteria; always confirm qualification for your substrate and application.
What is the difference between FAR 25.853, 25.855, and 25.856?
25.853 covers cabin compartment interior flammability; 25.855 covers cargo and baggage compartment liners; and 25.856 covers thermal/acoustic insulation, including burnthrough resistance. Many aerospace tapes are qualified to more than one of these depending on where they're installed.
Not sure which 25.853-tested tape you need?
Tell us the application, the spec or paragraph called out on your drawing, and the quantity, and we'll confirm the right flame-retardant tape, stocked sizes, lead time, and pricing. Certificate of Conformance available on request.
Ask Our Team →This guide is provided for general reference and is drawn from 14 CFR § 25.853 and Appendix F to Part 25. Regulatory citations and test criteria may be amended; always verify current requirements against the controlling regulation, the FAA Aircraft Materials Fire Test Handbook, and your applicable drawing or material specification. Boeing, BMS, BAC and BSS are trademarks of The Boeing Company; Airbus, ABD and ABS are trademarks of Airbus; other marks belong to their respective owners. Typical product test values are stated at time of manufacture and are not for use in writing specifications. Tape compliance must be established for the specific tape-and-substrate combination as installed.