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Senior Radiation Shielding Engineer



El Segundo, CA, USA
Posted on Wednesday, December 6, 2023

Radiant Industries is an El Segundo, CA-based startup developing Kaleidos, a portable, containerized nuclear microreactor. Portable nuclear power with rapid deploy capability can replace diesel generators used today to provide critical asset support for hospitals, datacenters, and military bases or to power microgrids at remote sites. Radiant’s unique, practical approach to nuclear development utilizes modern software engineering to rapidly achieve safe, factory-constructable microreactors leveraging existing, well-qualified materials. Radiant is on a fast track to demonstrate the first fueled operation of a new commercial nuclear reactor design, just three years from now.

Senior Radiation Shielding Engineer

Radiant is seeking a talented nuclear radiation shielding engineer to design, analyze, and develop shielding solutions for the 1 MW Kaleidos nuclear microreactor. You will design, test, and iterate on complex shielding designs optimized for a portable system. This role requires creative problem solving, first principles understanding, and an interdisciplinary mindset. The ideal candidate has the drive and tenacity to solve interesting technical challenges and are excited to commercialize a nuclear microreactor to power remote areas and microgrids anywhere.


  • Own and drive design and analysis of radiation shielding, including assessing reactor pressure vessel and system component activation, fuel handling requirements, and transportation/storage requirements.
  • Perform trade studies of optimal approaches balancing safety, size, mass, cost, and performance.
  • Perform complex dose calculations with MCNP, OpenMC, and/or SCALE, and use these findings to inform on design decisions.
  • Assess radiological conditions during transport, operation, including self-activation, environmental activation, and waste categorization.
  • Provide expertise and feedback via clear and constructive communication cross-functionally.
  • Develop and see through technical requirements for hardware systems, structures, and components, and lead design reviews.
  • Own shielding schedule, including design, manufacturing, and testing.
  • Find and develop suppliers for all components.
  • Own regulatory and quality compliance as related to shielding.

Required Qualifications and Skills:

  • Bachelor’s degree in nuclear engineering or equivalent degree from accredited institution.
  • 5+ years nuclear engineering industry experience.
  • Experience in academia and/or industry in shielding.
  • Proficient in MCNP, OpenMC, or SCALE.

Desired Qualifications and Skills:

  • Master’s or PhD in nuclear engineering or equivalent degree from accredited institution.
  • Hands on experience designing or owning hardware and/or performing tests.
  • Self-motivated to solve complex technical problems in a collaborative, fast-paced startup environment.
  • Software development experience in C, C++, or Python.
  • Proficient with general nuclear tools such as: MOOSE, Serpent, Attila, BISON, RELAP, CFD, or other nuclear software packages.

Employee Benefits for Eligible Employees:

  • Stock: Substantial incentive stock plan for all full time, salaried employees.
  • Medical: 100% up to base silver level plan for employee + 50% dependents, offers up to Platinum plans.
  • One Medical: Sponsored memberships for employees and their dependents.
  • Vision: 100% top tier plan coverage + 50% for dependents.
  • Dental: 100% top tier plan coverage, orthodontia extra, 50% for dependents.
  • Voluntary Life, Accident, Hospital, Critical Illness, Commuter and FSA are offered as employee contributed benefits.
  • Free snacks and drinks onsite.
  • Vacation/Sick time.

We are an equal opportunity employer and all qualified applicants will receive consideration for employment without regard to race, color, religion, sex, sexual orientation, gender identity or expression, pregnancy, age, national origin, disability status, genetic information, protected veteran status, or any other characteristic protected by law.

Unfortunately, we are unable to provide visa sponsorship at this time.This position involves access to technology that is subject to U.S. export controls. Any job offer made will be contingent upon the applicant’s capacity to serve in compliance with U.S. export controls.