Senior Safety Methods Engineer (Nuclear)

Location: Bellevue, Washington, United States

Salary: $138,685–$208,027 per year; the range is specific to Washington State.

Company

hirify.global is a nuclear technology company developing advanced nuclear reactors, hybrid energy systems, and medical isotope applications.

What you will do

• Develop system-level thermal hydraulic analysis methods, including modeling strategies, numerical approaches, closure models, and empirical correlations.
• Perform steady-state and transient analyses to characterize model behavior, method performance, and fidelity requirements.
• Support method qualification through numerical verification, applicability envelope definition, performance characterization, and sensitivity studies.
• Develop automated workflows and tools for model setup, execution, post-processing, and repeatable method application.
• Document methodologies, assumptions, applicability, and numerical performance for design and licensing support.
• Integrate thermal hydraulic methods with plant design, safety analysis, coupled simulations, and SQA/NQA 1 modeling practices.

Requirements

• Degree in Mechanical, Nuclear, Chemical Engineering, or a similar field, with 3+ years of system-level thermal hydraulic modeling and method development experience in nuclear or complex energy systems.
• Experience with numerical scheme development, closure model formulation, and stability and accuracy optimization.
• Experience using RELAP5 3D, GOTHIC, SAS, or equivalent system-level thermal hydraulic analysis tools.
• Strong knowledge of thermal fluids, reactor system behavior, and thermal hydraulic phenomena relevant to advanced reactors.
• Familiarity with Python or MATLAB, workflow automation, sensitivity analysis, model gap identification, and NQA 1 quality assurance for modeling workflows.
• Applicants are subject to U.S. Government export control review; foreign nationals may require export authorization. The role is subject to ANSI/ANS 3.1 qualification requirements and relevant nuclear industry experience criteria.

Culture & Benefits

• Work on advanced nuclear reactor research and development, including the Natrium Demonstration reactor.
• Comprehensive medical, vision, dental, life, disability, and wellness benefits.
• 401(k) plan, discretionary short-term incentive eligibility, and 21 days of accrued annual PTO.
• Ten paid holidays, parental leave, gender affirmation benefits, and relocation assistance.
• Professional and educational support opportunities.

Hiring process

• Employment verification includes verification of candidate data and assessment against applicable education and experience criteria.
• Export control status information may be requested during the application process.