(8)
Burn length : Burnlengthis the distancefrom the originaledge to thefarthest evidence of damage to the test specimen due to .ame impingement, including areas of partial or complete consumption, charring, or embrittlement, but not including areas sooted, stained, warped, or discolored, nor areas where material has shrunk or melted away from the heat source.]
Amdt. 25-72, E.. 8/20/90
′
Elodie Roux. Septembre 2003
Appendix F
FAR 25.F2 : Appendix F–Part II–Flammability of Seat Cushions.
(a)
Criteria for Acceptance. Each seat cushion must meet the following criteria :
(1)
At least three sets of seat bottom and seat back cushion specimens must be tested.
(2)
If the cushion is constructed with a .re blocking material, the .re blocking material must completely enclose the cushion foam core material.
(3)
Each specimentested mustbefabricated using theprincipal components(i.e., foamcore, .otationmaterial,.reblockingmaterial,if used, anddresscovering) and assemblyprocesses(representative seams and closures) intendedfor use in the production articles. If a di.erent material combination is used for the back cushion than for the bottom cushion, both material combinations must be tested as complete specimen sets, each set consisting of a back cushion specimen and a bottom cushion specimen. If a cushion, including outer dress covering, is demonstrated to meet the requirements, of this Appendix using the oil burner test, the dress covering of that cushion may be replaced with a similar dress covering provided the burn length of the replacement covering, as determined by the test speci.ed in [Sec. 25.853(c),] does not exceed the correspondingburnlength of the dress covering used on the cushion subjected to the oil burner test.
(4)
For at least two-thirds of the total number of specimen sets tested, the burn length from the burner must not reach the side of the cushion opposite the burner.Theburnlength must not exceed17inches.Burnlengthis theperpen-dicular distance from the inside edge of the seat frame closest to the burner to the farthest evidence of damage to the test specimen due to .ame im-pingement, including areas of partial or complete consumption, charring, or embrittlement, but not including areas sooted, stained, warped, or discolored, or areas where material has shrunk or melted away from the heat source.
(5)
The averagepercentage weightloss must not exceed10percent.Also, atleast two-thirds of the total number of specimen sets tested must not exceed 10 percent weight loss. All droppings falling from the cushions and mounting stand aretobediscardedbeforethe after-test weightisdetermined.Theper-centage weight loss for a specimen set is the weight of the specimen set before testing less the weight of the specimen set after testing expressed as the per-centage of the weight before testing.
(b)
Test Conditions. Vertical air velocity should average 25 fpm ± 10 fpm at the top of theback seatcushion.Horizontal airvelocity shouldbebelow10fpmjust above the bottom seat cushion. Air velocities should be measured with the ventilation hood operating and the burner motor o..
(c)
Test Specimens.
(1)
For each test, one set of cushion specimens representing a seat bottom and seat back cushion must be used.
(2)
The seat bottom cushion specimen must be 18±1/8inches(457±3mm)wide by 20±1/8 inches(508±3mm)deep by 4±1/8 inches(102±3mm)thick, exclusive of fabric closures and seam overlap.
(3)
The seat back cushion specimen must be 18 ±1/8 inches(432±3mm) wide by 25± 1/8 inches(635 ± 3mm) high by 2 ± 1/8 inches(51 ± 3mm) thick, exclusive of fabric closures and seam overlap.
(4) The specimens must be conditioned at70±5'F(21±2'C)55% ± 10% relative
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本文链接地址：FAA规章 美国联邦航空规章 Federal Aviation Regulations 4(50)
