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439 

Federal Aviation Administration, DOT 

Pt. 25, App. F 

(6) 

Instrumentation. 

Provide a recording po-

tentiometer or other suitable calibrated in-
strument with an appropriate range to meas-
ure and record the outputs of the calo-
rimeter and the thermocouples. 

(7) 

Timing device. 

Provide a stopwatch or 

other device, accurate to 

±

1%, to measure 

the time of application of the burner flame 
and burnthrough time. 

(8) 

Test chamber. 

Perform tests in a suitable 

chamber to reduce or eliminate the possi-
bility of test fluctuation due to air move-
ment. The chamber must have a minimum 
floor area of 10 by 10 feet (305 by 305 cm). 

(i) 

Ventilation hood. 

Provide the test cham-

ber with an exhaust system capable of re-
moving the products of combustion expelled 
during tests. 

(c) 

Test Specimens. 

(1) 

Specimen preparation. 

Prepare a minimum of three specimen sets of 
the same construction and configuration for 
testing. 

(2) 

Insulation blanket test specimen. 

(i) For batt-type materials such as fiber-

glass, the constructed, finished blanket spec-
imen assemblies must be 32 inches wide by 36 
inches long (81.3 by 91.4 cm), exclusive of 
heat sealed film edges. 

(ii) For rigid and other non-conforming 

types of insulation materials, the finished 
test specimens must fit into the test rig in 
such a manner as to replicate the actual in- 
service installation. 

(3) 

Construction. 

Make each of the speci-

mens tested using the principal components 
(

i.e., 

insulation, fire barrier material if used, 

and moisture barrier film) and assembly 
processes (representative seams and clo-
sures). 

(i) 

Fire barrier material. 

If the insulation 

blanket is constructed with a fire barrier 
material, place the fire barrier material in a 
manner reflective of the installed arrange-
ment For example, if the material will be 
placed on the outboard side of the insulation 
material, inside the moisture film, place it 
the same way in the test specimen. 

(ii) 

Insulation material. 

Blankets that uti-

lize more than one variety of insulation 
(composition, density, etc.) must have speci-
men sets constructed that reflect the insula-
tion combination used. If, however, several 
blanket types use similar insulation com-
binations, it is not necessary to test each 
combination if it is possible to bracket the 
various combinations. 

(iii) 

Moisture barrier film. 

If a production 

blanket construction utilizes more than one 
type of moisture barrier film, perform sepa-
rate tests on each combination. For example, 
if a polyimide film is used in conjunction 
with an insulation in order to enhance the 
burnthrough capabilities, also test the same 
insulation when used with a polyvinyl fluo-
ride film. 

(iv) 

Installation on test frame. 

Attach the 

blanket test specimens to the test frame 
using 12 steel spring type clamps as shown in 
figure 7. Use the clamps to hold the blankets 
in place in both of the outer vertical 
formers, as well as the center vertical former 
(4 clamps per former). The clamp surfaces 
should measure 1 inch by 2 inches (25 by 51 
mm). Place the top and bottom clamps 6 
inches (15.2 cm) from the top and bottom of 
the test frame, respectively. Place the mid-
dle clamps 8 inches (20.3 cm) from the top 
and bottom clamps. 

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