Lead Nuclear Criticality Safety Engineer

Protingent; Oak Ridge (TN); On-site; USD 110,000 - 160,000; Full time

Job summary

Protingent Staffing is seeking a Lead Nuclear Criticality Safety Engineer for a direct hire role in Oak Ridge, TN. You will lead criticality safety analyses for movement and storage of nuclear fuel, and validate configurations to prevent subcriticality under a range of transport and handling scenarios.

The role requires 5+ years of experience, expertise with MCNP or SCALE/KENO, and familiarity with ANSI/ANS-8 standards and NQA-1 quality requirements. On-site at Oak Ridge; relocation supported.

Qualifications

• Degree in Nuclear Engineering, Physics, or related technical discipline.
• 5+ years of nuclear criticality safety experience with authorship and independent defense of evaluations.
• Experience with MCNP/SCALE/KENO or equivalent.
• Familiarity with ANSI/ANS-8 standards and regulatory interfaces.
• Experience with HALEU, fuel handling, and transport safety.

Responsibilities

• Perform criticality safety analyses for movement of fresh and irradiated fuel between facilities and reactor sites.
• Define storage configurations and ensure subcriticality constraints on site fuel storage.
• Model accident scenarios to establish preventive and mitigative controls.
• Coordinate with design, performance, and transportation teams to maintain safe configurations.
• Document evaluations and configurations under quality and regulatory standards.

Skills

Criticality safety

Regulatory compliance

Cross-functional collaboration

Analytical modeling

Transportation safety

Education

Nuclear Engineering or Physics degree

Tools

MCNP

SCALE/KENO

ANSI/ANS-8 standards

ASME NQA-1

10 CFR Part 50 Appendix B

Job description

Job Description

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

Position Title:

Lead Nuclear Criticality Safety Engineer

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.