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Relap5 Jobs (NOW HIRING)

Develop RELAP5-3D models for steady state and transient one-dimensional network hydraulic analyses. * Develop plant level control strategy and component level controller. * Perform calculations using ...

Develop and document sensitivity studies using RELAP5, SAS, or GOTHIC to demonstrate efficacy of methodology approach. * Develop and document code benchmarking and validation analyses to support code ...

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How much do relap5 jobs pay per hour?

As of May 30, 2026, the average hourly pay for relap5 in the United States is $50.17, according to ZipRecruiter salary data. Most workers in this role earn between $39.42 and $60.82 per hour, depending on experience, location, and employer.

What are the key skills and qualifications needed to thrive as a RELAP5 Nuclear Safety Analyst, and why are they important?

To thrive as a RELAP5 Nuclear Safety Analyst, you need a solid background in nuclear engineering, thermohydraulics, and reactor safety analysis, usually supported by an engineering degree. Proficiency in using the RELAP5 simulation software, understanding of nuclear regulatory codes, and familiarity with data analysis tools are essential technical requirements. Strong analytical thinking, attention to detail, and effective communication skills help you interpret complex data and collaborate with multidisciplinary teams. These capabilities are vital to ensure accurate safety assessments and compliance with regulatory standards in nuclear power plant operations.

What is RELAP5?

RELAP5 is a computer code developed by Idaho National Laboratory for the analysis of thermal-hydraulic behavior in nuclear reactor systems during normal and accident conditions. It is widely used by engineers and researchers to simulate the behavior of reactor coolant systems, particularly in light water reactors. RELAP5 models fluid flow, heat transfer, and reactor system response, providing valuable insights for safety analysis and design improvements.

What is the difference between Relap5 vs Relap5?

AspectRelap5Relap5

Since the comparison is between the same job title, there is no difference in skills, credentials, or work environment. Both roles involve using Relap5 software for thermal-hydraulic safety analysis in nuclear engineering, requiring similar certifications and industry experience. Typically, professionals in this role work in nuclear power plants, research facilities, or engineering firms focused on nuclear safety. The primary distinction may lie in specific project focus or experience level, but overall, the roles are equivalent.

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What cities are hiring for Relap5 jobs? Cities with the most Relap5 job openings:
What states have the most Relap5 jobs? States with the most job openings for Relap5 jobs include:
Infographic showing various Relap5 job openings in the United States as of May 2026, with employment types broken down into 2% Internship, 84% Full Time, and 14% Contract. Highlights an 86% Physical, 12% Hybrid, and 2% Remote job distribution, with an average salary of $104,344 per year, or $50.2 per hour.
RELAP5-3D Code Developer and Analyst

RELAP5-3D Code Developer and Analyst

Idaho National Laboratory

Idaho Falls, ID • On-site

$79.34K - $162.73K/yr

Full-time

Medical, Dental, Vision, Retirement, PTO

This job post has expired today. Applications are no longer accepted.


Idaho National Laboratory rating

8.8

Company rating: 8.8 out of 10

Based on 16 frontline employees who took The Breakroom Quiz

12th of 103 rated laboratories


Job description

As a pivotal member of Idaho National Laboratory's groundbreaking team, you'll push the boundaries of innovation by developing, testing, and refining cutting-edge models that drive advancements in nuclear energy and beyond. Your expertise will shape the future of American energy security and technological leadership, building on INL's legacy of firsts and helping to secure critical infrastructure in a rapidly evolving world. Working at the forefront of scientific discovery, you'll turn complex data into transformative insights, accelerating breakthroughs in energy, national security, and space exploration. Your contributions will directly support INL's mission to pioneer solutions that power the nation and protect its resilience. This is your chance to leave a lasting impact on history, alongside a team of brilliant scientists and engineers committed to shaping America's technological future.

Position Overview: INL is seeking a skilled and forward-thinking Developer to join the Reactor Systems and Heat Transport Department as part of the RELAP5-3D team in modernizing and expanding the capabilities of this critical nuclear safety analysis tool. This role involves improving code structure, readability, and maintainability, while also supporting the integration of new features and tools. The ideal candidate will be passionate about clean code practices and eager to contribute to a high-impact nuclear safety software platform. Additionally the developer will have the ability to perform thermal hydraulic analysis using RELAP5-3D to determine areas of improvement.  

Key Responsibilities: 

  • Update legacy Fortran code to modern standards, including restructuring. 
  • Break down complex routines into manageable components through refactoring and enhancing inline documentation. 
  • Program new code features, capabilities, and algorithms in Fortran as assigned and use existing and new write Python scripts. 
  • Apply the automated documentation systems to streamline manual creation and updates. 
  • Submit code updates as pull requests to the repository. 
  • Participate in the International RELAP5 User Group (IRUG) Meetings. 
  • Collaborate with analysts, stakeholders, and external partners to support ongoing development and integration efforts. 
  • Perform thermal hydraulic design/safety analysis using RELAP5-3D or other thermal hydraulic tools.  

Required:

  • Level 1: Bachelor's in Computer Science, Software Engineering, Mechanical Engineering, Nuclear Engineering, Mathematics or a related field. 
  • Level 2: Bachelor's Computer Science, Software Engineering, Mechanical Engineering, Nuclear Engineering, Mathematics or a related field (2) years of relevant experience; or advanced degree in Computer Science, Software Engineering, Mechanical Engineering, Nuclear Engineering, Mathematics or a related field. 

  • This position requires the ability to obtain and maintain a "Q" clearance, which requires U.S. Citizenship. 

  • Proficiency in programming is required: 
    • Proficiency will be used to assess level, ranging from proficiency with basic scripting languages like Python, Matlab or javascript to compiled languages, e.g., C++ or Fortran. Proficiency in Fortran is a plus.  
  • Familiarity with software development tools and version control systems (e.g., Git). 

    • Must be good at typing and working with text-based input. 
    • Strong problem-solving skills and attention to detail 

Preferred Qualifications: 

  • Experience with RELAP5-3D or similar nuclear system codes. 
  • Exposure to DOE programs, nuclear reactor modeling, or simulator development. 
  • Experience with software refactoring, code modernization, and technical documentation. 
  • Knowledge of numerical methods and linear algebra 
     

Physical Requirements:

While performing the duties of this classification, the employee is frequently required to stand, walk, sit, stoop, kneel, bend, use hands to handle materials, manipulate tools, keyboard and type, reach with hands and arms, and operate job-related equipment. The employee must occasionally lift and/or move up to 25 pounds. Sufficient visual acuity and hearing capacity to perform the essential functions and interact with people is required. Reasonable accommodations may be made to enable individuals with disabilities to perform the essential functions.

Job Information:

  • Idaho National Laboratory is seeking a Modeling and Simulation Engineer. Our team works a 9x80 schedule located out of our Idaho Falls facility with every other Friday off. 
  • The pay range for this position is: Level 1 ($66,504-$136,356) /Level 2 ($79,344 - $162,732). At Idaho National Laboratory compensation decisions are determined using factors such as education, relevant experience, and other credentials.
  • TDP: This is a testing designated position; you will be required to submit to a pre-employment drug screen and periodic drug testing throughout the term of your employment. 
  • Multi-Level: This is a multi-level posting and you will be placed at the appropriate level dependent on depth and breadth of proven experience and skills. 

Benefits and Relocation

  • Medical, Dental, Vision, and Flexible Spending Accounts
  • 401(k) with a 4.2% employer contribution and up to 4.8% match (regular positions) or self-contribute access (postdoctoral positions)
  • Paid time off (personal leave)
  • Employee Education Program (tuition assistance for eligible positions)
  • Comprehensive Relocation Package
  • Benefit eligibility subject to multiple factors, including employment status and position classification.

At this time, BEA will not sponsor any H1-B visas obtained outside of the United States of America (U.S.A.), including consular visas.

INL is a science-based, applied engineering national laboratory dedicated to supporting the U.S. Department of Energy's mission in nuclear energy research, science, and national defense. With more than 6,300 scientists, researchers, and support staff, the laboratory works with national and international governments, universities and industry partners to change the world's energy future and secure our nation's critical infrastructure.

INL Mission:

Our mission is to discover, demonstrate and secure innovative nuclear energy solutions, other clean energy options and critical infrastructure.

INL Vision:

Our vision is to change the world's energy future and secure our nation's critical infrastructure.

Selective Service Requirements:

To be eligible for employment at INL males born after December 31, 1959 must have registered with the Selective Service System (SSS). For more information see www.sss.gov.

Equal Employment Opportunity:

Idaho National Laboratory (INL) is an Equal Employment Opportunity (EEO) employer. It is the policy of INL to provide equal employment opportunities to all qualified applicants without regard to race, color, religion, sex, sexual orientation, gender identity, national origin, age, protected veteran or disabled status, or genetic information.

Reasonable Accommodation:

We will ensure that individuals with disabilities are provided reasonable accommodation to participate in the job application or interview process, to perform essential job functions, and to receive other benefits and privileges of employment. Please contact us to request accommodation.

Other Information:

When applying to positions please provide a resume and answer all questions on the following screens. Applicants, who fail to provide a resume or answer the questions, may be deemed ineligible for consideration.

INL does not accept resumes from third party vendors unsolicited.

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About Idaho National Laboratory

Sourced by ZipRecruiter

Idaho National Laboratory is a leading multi-disciplinary national laboratory dedicated to supporting the U.S. Department of Energy's missions in nuclear and energy research, science, and national defence. Located in Idaho Falls, ID, US, it operates under the management of Battelle Energy Alliance. Since its inception in 1949, the lab has remained at the forefront of nuclear energy innovations and advancements, providing critical scientific and technological inputs to support national priorities. Guided by its commitment to excellence, innovative research, collaborative partnerships, and integrity, the lab continues to play a vital role in driving America's nuclear and energy future.

Industry

Scientific research and development services

Company size

5,001 - 10,000 Employees

Headquarters location

Idaho Falls, ID, US

Year founded

1949

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