The mission of Technical Area 18 (TA-I 8) at the National Nuclear Security
Administration's (NNSA) Los Alamos National Laboratory (Los Alamos) was to conduct
nuclear criticality experiments and hands-on training in nuclear safeguards, criticality
safety and emergency response. TA-18 was the only facility in the United States capable
of performing these nuclear criticality experiments needed to validate safety evaluations,
establish limits for operations involving special nuclear material (SNM), and provide
criticality training. Experiments were performed on five one-of-a-kind criticality
machines and required a diverse set of SNM and highly skilled technical personnel.