Save for later Print Download Share LinkedIn Twitter The US Nuclear Regulatory Commission's (NRC) rejection of Oklo's application to build a micro reactor was unprecedented but also highlighted the need for a new set of rules governing small modular reactors (SMRs) and advanced reactors. An effort is under way to come up with such rules but it won't be finalized until at least 2025, so to cover expected applications before then from TerraPower and X-energy, and likely a new application from Oklo, the agency is relying on existing regulations that were developed to govern large light-water reactors.