What is ISO 21391- Geometrical dimensions for subcriticality control about?
ISO 21391 is an International Standard on nuclear criticality safety.
ISO 21391 provides guidance, requirements and recommendations related to determination of limits on subcriticality dimensions and ensuring compliance with:
- Geometrical dimensions specified in the design (design dimensions)
- Actual dimensions
ISO 21391 is applicable to nuclear facilities containing fissile materials, except nuclear power reactor cores. ISO 21391 can also be applied to the transport of fissile materials outside the boundaries of nuclear establishments. Subcriticality dimension control based on dimensions and layout of the fuel assembly, fuel rods, and fuel pellets are not covered by this document.
Note: BS ISO 21391 does not specify requirements related to the control of fissile and non-fissile material compositions.
Who is ISO 21391- Geometrical dimensions for subcriticality control for?
ISO 21391 on nuclear criticality safety is relevant to:
- Nuclear power plants
- Organizations involved with fissile material and nuclear fuel technology
- Atomic research organizations
- Regulatory authorities
- Nuclear research organizations
- Product design engineers
- Fabricators
Why should you use ISO 21391- Geometrical dimensions for subcriticality control?
Nuclear criticality safety is a branch of nuclear engineering concerned with preventing nuclear and radiation accidents caused by an unintentional, self-sustaining nuclear chain reaction. The goal of nuclear criticality safety is to minimize the consequences of a nuclear criticality disaster.
ISO 21391 covers subcriticality control based on geometrical dimensions, called subcriticality dimensions, related to equipment and layout.
ISO 21391 provides best industry guidance on subcriticality dimensions, performing specific subcriticality calculations, subcriticality limits, and actual dimension control.
Overall, compliance with ISO 21391 on the control of the geometry can help establish and maintain nuclear critical safety of fissile units.