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EP93FRHT was developed for various bonding, sealing, coating, and encapsulation applications in aircrafts, where stringent requirements for flame retardancy, smoke emission, and toxicity levels have to be met.

To prepare for the Airbus tests, castings of Master Bond EP93FRHT epoxy were made. The first test is the vertical ignition test (conducted in accordance with Airbus AITM 2.0002B, Issue 2 for specification ABD0031, Issue F, Section 7.1.2). The casting specimen was exposed to certified pure bottled methane for 12 seconds. The results show that it took under 1 second to extinguish the flames, well under the allotted 15 seconds permitted by the test.

The second part of this test measures how far the flame has spread. Again, EP93FRHT depicts a burned length of just over 7 mm. Once again, well under the maximum allowed of 203 mm. Airplane interiors that might be tested for the 12 second vertical burn test include carpeting and other floor coverings, upholstery, seat cushions, and air ducting.

The next Airbus test is the optical density of smoke generated by solid materials (conducted in according with AITM 2.0007B, Issue 3 for specification Airbus Document ABD0031, Issue F, Section 7.3.2). In this test, the epoxy casting is exposed to a flame for 60 seconds after which a successful result would show that the smoke being generated is below the threshold of 200 specific optical density (Ds). Master Bond EP93FRHT passes with flying colors, with a Dmax of 137. (Please refer to chart below.) This Airbus test may be used on interior wall panels, aircraft doors, and stowage compartments.

Specific Optical Density, Ds of Smoke Generated by Solid Materials

Time from Initiation (seconds) Specimen: EP93FRHT
0-60 0
90 17
120 36
150 63
180 103
210 116
240 137
Time to Dmax (seconds) 3:59.6

Last, we have the toxic gas analysis of the smoke that was generated. At the end of the smoke test, 4 minutes after initiation, the specimen is tested for toxicity to certain reactive gases, like carbon monoxide, hydrogen chloride, nitric oxides, sulfur dioxide, hydrogen cyanide and hydrogen fluoride. In this next chart, you can see the acceptance criteria for toxicity specified by the Airbus test, ABD0031 Issue F, Section 7.4 per AITM 3.005, Issue 2,and that the values of the Master Bond epoxy fall well below each.

Toxic Gas Analysis of Smoke: Flaming exposure 4 minutes after start of AITM 2.0007B

NO+NO2 HCN SO2 HF
47.2 - 4 -
Average 49.3 15 5 0 (No Indication)
Standard Deviation 10.5 n/a 1 n/a
Maxiumum Allowed 100 150 100 100

Master Bond EP93FRHT is a two component epoxy that can be used as an adhesive, sealant and encapsulating system. It also is widely used for potting electronic components. To learn more about this specialty product, please contact a technical advisor today.

*Disclaimer: The results of these tests were determined under controlled laboratory conditions and are not necessarily representative of the behavior of the material under actual fire conditions. However, the results of these tests may be used as elements of a fire risk assessment that takes into account all of the factors that are pertinent to its end use.