To protect people and the environment from ionising radiation released from nuclear installations and nuclear materials, the following four safety objectives must be complied with:

• Safety objective 1: Control of reactivity,
• Safety objective 2: Cooling of the fuel elements,
• Safety objective 3: Containment of radioactive materials,
• Overarching safety objective 4: Limiting of radiation exposure.

Each safety objective is based on several partial safety objectives and safety objective functions. This sub-division is not regulated in a uniform manner at the international level and to a certain extent is installation specific.