Lead Nuclear Criticality Safety Engineer

Protingent; Oak Ridge (TN); On-site; USD 120,000 - 180,000; Full time

Job summary

Protingent seeks a Lead Nuclear Criticality Safety Engineer in Oak Ridge, TN to drive safety analyses and ensure subcritical configurations across fuel handling, storage, and transport. You will develop and defend criticality evaluations, coordinate with design and logistics teams, and lead HALEU-related safety work.

The role requires deep expertise in MCNP/ SCALE, ANSI/ANS-8 standards, and ASME NQA-1 with strong QA discipline. Onsite work with a focus on moving and storing nuclear material.

Qualifications

• Requires degree in Nuclear Engineering, Physics, or related technical field.
• 5+ years of nuclear criticality safety experience with authorship and defense of evaluations.
• Demonstrated ability to validate computa tional methods and subcritical margins.
• Familiarity with ANSI/ANS-8 standards and related safety controls.

Responsibilities

• Perform criticality safety analyses for fuel movement and transport to reactor sites or between facilities.
• Define and validate storage configurations for fresh and spent fuel to maintain subcritical margins.
• Model and analyze accident scenarios (inadvertent moderation, geometry changes) to support controls.
• Collaborate with fuel design, performance, and transport teams to ensure safe configurations.
• Anchor evaluations and reports under configuration control per NQA-1 and regulatory standards.
• Define and approve safety basis for HALEU-bearing materials and related shipments.

Skills

Criticality safety leadership

MCNP/SCALE/KENO

Computational methods

Nuclear QA & NQA-1

ANSI/ANS-8 standards

HALEU experience

Fissile material handling

Education

Nuclear Engineering degree

Tools

ASME NQA-1 compliance

10 CFR Part 50 Appendix B

Job description

Position Title: Lead Nuclear Criticality Safety Engineer

Position Description:

Protingent Staffing has an exciting direct hire Lead Nuclear Criticality Safety Engineer opportunity.

Job Responsibilities:

• Handling & Transport Analysis: Execute comprehensive criticality safety analyses for the movement of fresh and irradiated fuel, including transport to reactor sites and inter-facility transfers.
• Storage Configuration Validation: Define and validate the geometric and moderation constraints for the on-site storage of both fresh fuel blocks and spent fuel arrays, ensuring strict adherence to subcriticality limits.
• Accident Scenario Modeling: Identify, model, and analyze potential out-of-pile criticality accident scenarios (e.g., inadvertent moderation, geometric reconfiguration during handling drops) to establish robust preventive and mitigative controls.
• Cross-Functional Safety Integration: Work with the fuel design, performance, and transportation teams to ensure all fuel handling equipment and transport casks maintain inherently safe geometric configurations.
• Configuration Management: Anchor all criticality safety evaluations, validation reports, and operational limit documentation within configuration control, ensuring strict compliance with ASME NQA-1 and NRC regulatory standards.
• Qualification Campaign Criticality Safety: Define and approve the criticality safety basis for HALEU-bearing qualification materials, fuel lots, test specimens, fabrication steps, packaging, inter-facility shipments, irradiation support, PIE handling, and waste or residue dispositions.

Job Qualifications:

• Education: Degree in Nuclear Engineering, Physics, or a related highly technical discipline.
• Criticality Safety Leadership: 5+ years of nuclear criticality safety experience, including authorship and independent defense of evaluations for fissile-material processing, laboratories, storage, or transportation.
• Validated Computational Methods: Demonstrated ability to establish code validation, benchmark applicability, calculational bias and uncertainty, and subcritical margins using recognized critical experiments and sensitivity or similarity methods.
• Proficiency with industry-standard criticality safety analysis codes (e.g., MCNP, SCALE/KENO).
• Standards & Controls: Working knowledge of applicable ANSI/ANS-8 standards, double-contingency principles, criticality alarm and emergency-planning interfaces, and implementation of engineered and administrative controls.
• HALEU & Heterogeneous Fuel: Experience analyzing enriched uranium, powders or kernels, TRISO particles, graphite or ceramic moderation, arrays, reflection, interaction, and credible upset conditions across changing process configurations.
• Nuclear QA & Software Control: Experience preparing configuration-controlled evaluations and calculation packages under ASME NQA-1, 10 CFR Part 50 Appendix B, DOE, or equivalent nuclear software-quality requirements.

Preferred Job Qualifications:

• Direct experience analyzing TRISO-based fuels, High-Assay Low-Enriched Uranium (HALEU), or graphite moderated fuel elements.
• Background coordinating with transport security or logistics partners on nuclear material movement.
• Familiarity with the specific criticality safety challenges inherent to refueling operations.

Job Details:

Job Type: Full-time Salary Range: TBD Location: Oak Ridge, TN(Onsite)

About Protingent:

Protingent is an Award-Winning provider of top-tier Engineering and IT talent, trusted by companies at the forefront of innovation — from Software and Aerospace to AI, Clean Tech, Medical Devices, and Connected Technologies. We’re passionate about making a positive impact by connecting exceptional talent with meaningful opportunities and helping our clients build the future.