Chapter 2: Introduction to Nuclear Safety

Strengthened requirements for the design against external hazards

The revision 0 of SSR-2/1 was approved by the IAEA Commission on Safety Standards in March 2011, exactly one week after the dramatic accident at Fukushima-Daiichi. The Revision 1 of this standard (published in 2016) included strengthened requirements for the design against external hazards, including lessons learnt from that accident.

SSR-2/1 (Rev. 1) Requirement 17 requires that the design of the plant shall provide for an adequate margin to protect items important to safety against levels of external hazards to be considered for design, derived from the hazard evaluation for the site, and to avoid cliff edge effects. The design of the plant shall also provide for an adequate margin to protect items ultimately necessary to prevent an early radioactive release or a large radioactive release in the event of levels of natural hazards exceeding those considered for design, derived from the hazard evaluation for the site.

Read more: SSR-2/1 (Rev. 1), TECDOC-1791