4.1 This test method is intended to screen the most obvious poor materials from further consideration. Since the combustion gases more closely resemble the environment generated in rocket motors, this test method is more applicable to screening materials for nozzles and motor liners than for aerodynamic heating.

4.2 The environment for any specific high-temperature thermal protection problem is peculiar to that particular application. The conditions generated by the oxyacetylene heat source in this test method represent only one set of conditions; they do not simulate any specific application. Thus, the test results cannot be used to predict directly the behavior of materials for specific environments, nor can they be used for design purposes. However, over a number of years, the test has been useful in determining the relative merit of materials, particularly in weeding out obviously poor materials from more advanced data-generation programs. It has also been considered for use as a production quality-control test for rocket insulation materials.

4.3 The tester is cautioned to use prudence in extending the usefulness of the test method beyond its original intent, namely, screening. For situations having environments widely different from those of the test, the user is urged to modify the oxyacetylene burner conditions to suit his requirements or perhaps change to a different heat-generating device that provides better simulation.