Test Series 3 is a compilation of tests to determine whether or not the material should be considered a high explosive (i.e. Division 1.1) or whether the material may be considered in a lower explosive category (e.g. Division 1.3). The test series contains four different tests: the thermal stability test, the small-scale burning test, the #8 cap test, and the card gap test.

Thermal Stability Test

This test is used to determine the reaction of samples when subjected to a mildly elevated temperature (75°C) for a specific period (48 hours). At the completion of the test, the sample is examined for discoloration, weight loss, and dimensional change as evidence of decomposition. Any evidence of explosion is also criteria for a positive result (i.e. fails the test).

Small-Scale Burning Test

This test is used to determine if unconfined samples, once ignited continue burning or transit to an explosion or detonation. A bed of sawdust, containing small samples of test material, is ignited and monitored. The test is a "go" (positive) if explosion or detonation occurs.

Explosive Cap Testing (No. 8 Cap)

The No. 8 cap test is used to determine susceptibility of explosives to detonation from the energy delivered by a standard detonator. Sample detonation is determined by examining the witness plate. The criterion for detonation (positive result) is that the witness plate is torn or penetrated.

NOL Card Gap Test

This test is similar to the UN gap test except that a shorter tube of material is used and a varied attenuator is placed between the test material and the pentolite booster. The attenuators provide a reduced shock source. The criterion for a "go" is that a clean hole is punctured through the witness plate. Typically, 12 trials are required to determine the 50% "go/ no-go" level. The test determines if a material will propagate an attenuated detonation.