Job Title: Principal/Senior Mechanical Engineer (Nuclear) Location: Warrington (Hybrid: 3 days onsite, 2 days WFH) Salary: Competitive Job Type: Permanent | Full Time About the Role iO Associates is currently working with a leading engineering organisation involved in major UK nuclear projects. We're recruiting for a Principal/ Senior Mechanical Engineer with expertise in bulk solids or powder handling systems, ideally for nuclear or other highly regulated sectors. This is a unique opportunity to contribute to the safe and effective management of radioactive or hazardous powdered materials-ranging from fuel fabrication to waste processing-within complex engineering environments. Multiple positions are avaliable. Key Responsibilities Lead the design, integration, and review of powder handling systems (e.g., hoppers, feeders, pneumatic conveyors, gloveboxes). Apply engineering standards and nuclear safety principles across all design and project stages. Produce and review technical documentation, including calculations, drawings, reports, and risk assessments. Collaborate with multi-disciplinary teams including nuclear safety, process, and systems engineers. Provide engineering oversight to ensure compliance with safety cases and relevant codes. Support customer engagement, stakeholder management, and technical mentoring of junior engineers. Essential Experience Background in mechanical engineering with strong exposure to bulk solids/powder handling, ideally in a regulated environment (nuclear, pharma, chemical, etc.). Proven ability to design or evaluate mechanical systems involving containment, flow control, or automated powder transfer. Experience in producing and reviewing detailed technical documents and engineering calculations. Collaborative approach to problem-solving across project teams. Desirable (But Not Essential) Experience with glovebox or hot cell design. Knowledge of critically safety, ALARP, and radiological containment. Prior exposure to nuclear decommissioning, new build, or fuel cycle facilities. Qualifications Degree preferred. Chartered or working towards professional registration (e.g., IMechE) is advantageous. ADZN1_UKTJ