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Criticality Safety Engineer

Associate | Full-time
Environmental, Safety & Health | livermore, CA | 04/15/2021

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Company Description

Join us and make YOUR mark on the World!

Are you interested in joining some of the brightest talent in the world to strengthen the United States’ security? Come join Lawrence Livermore National Laboratory (LLNL) where our employees apply their expertise to create solutions for BIG ideas that make our world a better place.

We are looking for individuals that demonstrate an understanding of working in partnership with team peers, who engage, advocate, and contribute to building an inclusive culture, and provide expertise to solve challenging problems.

Job Description

We have an opening for a Criticality Safety Engineer within the Environment, Safety, and Health (ES&H) Directorate.  You will contribute to the design, development, and testing of nuclear equipment and systems for Lawrence Livermore National Laboratory (LLNL) operations with fissionable materials.  You will also contribute to projects and task assigned to LLNL supporting the Department of Energy (DOE) Nuclear Criticality Safety Program (NCSP).   This position is in the Nuclear Criticality Safety Division (NCSD).

This position will be filled at either level based on knowledge and related experience as assessed by the hiring team. Additional job responsibilities (outlined below) will be assigned if hired at the higher level.

In this role you will

  • Perform criticality safety evaluations in conformance with DOE-STD-3007 and LLNL administrative procedures and participate in design and reviews of new or proposed changes to existing equipment or operating procedures.
  • Perform walkthrough inspections and basic annual reviews of operations and work authorization/work control documents and review safety procedures and documents for consistency with criticality safety evaluations and adequate implementation of criticality safety controls.
  • Perform technical/scientific assignments of moderate to complex problems that require independent analysis and creativity, and provide technical support to facility management, engineers and scientists in scientific research and development projects and/or ongoing operations.
  • Gather and analyze data and information in support of the work activity and deliver results in the form of documents, calculations, recommendations, corrective actions, or designs.
  • Develop creative solutions to problems of moderate complexity, contributing to the fulfillment of project and organizational goals.
  • Frequent travel to the Nevada National Security Site.
  • Conduct Fundamentals of Criticality Safety training courses.
  • Perform other duties as assigned.

Additional job responsibilities, at the SES.3 level

  • Prepare technical reports and present formal presentations to LLNL management and various internal and external audiences.
  • Conduct formal on-the-job training, informal presentations, and consultations of criticality safety information to fissile material handlers, designers, and other clients.
  • Interpret, implement, and provide guidance to internal customers on DOE regulations, national consensus criticality safety standards and Laboratory policies related to criticality safety.


  • Ability to obtain and maintain a U.S. DOE Q-level security clearance which requires U.S. Citizenship
  • Bachelor’s Degree in Nuclear Engineering, Physics, or closely related scientific discipline or the equivalent combination of education and related experience.
  • Comprehensive knowledge of and experience working in a nuclear facility, nuclear reactor, chemical, high hazard, (e.g., explosive), radiological operations, or similarly complex or highly regulated facility.
  • Broad application of technical, analytical and decision-making skills and record of achievement in performing criticality safety evaluations or research.
  • Proficient with personal computers and radiation transport software (e.g., COG, MCNP, SCALE).
  • Experience preparing technical documents following appropriate protocols (e.g., criticality safety evaluations, safety basis calculations, design calculations, and drawings/sketches).
  • Working knowledge of DOE orders, national consensus standards, and engineering practices.
  • Proficient verbal and written communication and interpersonal skills necessary to work effectively in a collaborative work environment.
  • Ability to document, present and/or explain technical or operational information and work results to management and stakeholders, i.e., DOE, DNFSB, and other external agencies.

Additional qualifications at the SES.3 level

  • Significant experience with nuclear and fissile material operations.
  • Significant experience conducting safety evaluations in conformance with applicable DOE orders.

Qualifications We Desire

  • Masters or Doctorate in Nuclear Engineering, Physics, or closely related discipline.
  • Experience in criticality safety and knowledge of LLNL’s policies, procedures, and practices.

Additional Information

Why Lawrence Livermore National Laboratory?

  • Included in 2021 Best Places to Work by Glassdoor!
  • Work for a premier innovative national Laboratory
  • Comprehensive Benefits Package
  • Flexible schedules (*depending on project needs)
  • Collaborative, creative, inclusive, and fun team environment

Learn more about our company, selection process, position types and security clearances by visiting our Career site

Security Clearance

LLNL is a Department of Energy (DOE) and National Nuclear Security Administration (NNSA) Laboratory.  Most positions will require a DOE L or Q clearance (please reference Security Clearance requirement).  If you are selected, we will initiate a Federal background investigation to determine if you meet eligibility requirements for access to classified information or matter. In addition, all L or Q cleared employees are subject to random drug testing.  An L or Q clearance requires U.S. citizenship.  If you hold multiple citizenships (U.S. and another country), you may be required to renounce your non-U.S. citizenship before a DOE L or Q clearance will be processed/granted.  For additional information please see DOE Order 472.2.

Equal Employment Opportunity

LLNL is an affirmative action and equal opportunity employer that values and hires a diverse workforce. All qualified applicants will receive consideration for employment without regard to race, color, religion, marital status, national origin, ancestry, sex, sexual orientation, gender identity, disability, medical condition, pregnancy, protected veteran status, age, citizenship, or any other characteristic protected by applicable laws.

If you need assistance and/or a reasonable accommodation during the application or the recruiting process, please submit a request via our online form

California Privacy Notice

The California Consumer Privacy Act (CCPA) grants privacy rights to all California residents. The law also entitles job applicants, employees, and non-employee workers to be notified of what personal information LLNL collects and for what purpose. The Employee Privacy Notice can be accessed here.

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