[3] The kiloton and megaton of TNT equivalent have traditionally been used to describe the energy output, and hence the destructive power, of a nuclear weapon.

The TNT equivalent appears in various nuclear weapon control treaties, and has been used to characterize the energy released in asteroid impacts.

For TNT this has been accurately measured as 4,686 J/g from a large sample of air blast experiments, and theoretically calculated to be 4,853 J/g.

[9] However even on this basis, comparing the actual energy yields of a large nuclear device and an explosion of TNT can be slightly inaccurate.

A large open explosion of TNT may maintain fireball temperatures high enough so that some of those products do burn up with atmospheric oxygen.

This enables engineers to determine the proper masses of different explosives when applying blasting formulas developed specifically for TNT.