Why would the Chernobyl design not have met U.S. licensing design requirements?

• A. It was an older design with major design weaknesses not acceptable in the U.S. licensing framework.
• B. It used a newer design not approved by US.
• C. It was a pressurized water reactor, not permitted.
• D. It had no containment structure.

Answer: (A)

Licensing design requirements in the U.S. are written to ensure a reactor has robust, proven safety features, strong containment, and defense-in-depth so that accidents are unlikely and their consequences are contained. The Chernobyl design, an older RBMK reactor, would not meet those standards because it carried major design weaknesses that modern licensing would flag. For one, the graphite-moderated core with a positive void coefficient can cause reactivity to increase as steam forms, making the reactor more difficult to control during transients. In addition, the safety systems and containment arrangement of that design were not aligned with the redundancy and proven safety margins expected in the U.S. framework. The combination of being an older design and having these significant vulnerabilities would render it noncompliant with U.S. licensing requirements.