Btu (15.8°C, ISO)
The British Thermal Unit (Btu) is a traditional unit of heat, defined as the amount of heat required to raise the temperature of one pound of water by one degree Fahrenheit. The Btu (15.8°C, ISO) is a specific variant standardized by the International Organization for Standardization (ISO) based on the calorie defined at 15.8°C.
Kilotons (explosive energy)
A kiloton is a unit of measurement that quantifies the energy released in an explosion. It is the energy released by detonating 1,000 tons of TNT (trinitrotoluene). One kiloton is approximately equal to 4.184 × 1012 joules.