pressure-change effects tend to "freeze" the burn rapidly. A large, open explosion of TNT may maintain fireball temperatures high enough that some of those products do burn up with atmospheric oxygen.

Such differences can be substantial. For safety purposes, a range as wide as has been stated for a gram of TNT upon explosion. Thus one can state that a nuclear bomb has a yield of 15 kt , but the explosion of an actual pile of TNT may yield (for example) due to additional carbon/hydrocarbon