Bomb calorimetry involves measuring the heat of combustion (calorific value) of fuels and other combustible materials. A bomb calorimeter consists of (1) a bomb vessel where combustion occurs, (2) a bucket containing water for absorbing heat, (3) an insulating jacket, and (4) a thermometer. The heat released by combusting a sample in oxygen is absorbed by water in the bucket, causing its temperature to rise. By comparing this rise to that of a standard material, the sample's calorific value can be calculated after applying corrections. Safety precautions must be followed when using high-pressure oxygen.