Industrial Hygienist Torrance, CA EHS

Castelion is moving incredibly fast to develop and deliver advanced defense systems at a time when execution matters more than ever. We believe focus, ownership, and excellence are decisive advantages - and we're building a world-class team to turn bold ideas into real capability.

This is a rare opportunity to join at an early stage, where you'll have significant ownership, collaborate with exceptional teammates, and make a direct, measurable impact on our mission and the future of the company - regardless of your function.

Department: Environmental, Health and Safety

Reports to: Site EHS Manager – Torrance

About the Role

Castelion is seeking an Industrial Hygienist to support our headquarters and manufacturing operations in Torrance, California. This individual will serve as a technical resource for industrial hygiene and occupational health across a diverse environment that includes advanced manufacturing, composites and materials, machining, research and development, avionics and dev test operations.

Reporting to the Site EHS Manager, the Industrial Hygienist will work closely with Engineering, Manufacturing, Facilities, and EHS team members to identify and characterize workplace exposures, establish effective controls, and integrate industrial hygiene considerations into new and evolving processes.

This is a hands-on role requiring regular engagement with employees and operations to understand how work is performed and translate technical industrial hygiene principles into practical solutions.

Responsibilities

• Develop and execute the site's industrial hygiene program, including exposure assessment strategies, sampling plans, monitoring, documentation, and periodic reassessment.
• Conduct qualitative and quantitative assessments of chemical and physical hazards across manufacturing, R&D, laboratory, and supporting operations, including airborne contaminants, noise, and non-ionizing radiation.
• Establish risk-based exposure monitoring strategies, including similar exposure groups, baseline characterization, monitoring frequencies, and reassessment criteria.
• Evaluate occupational exposure risks associated with advanced materials, chemicals, manufacturing processes, and emerging R&D activities, including situations where established exposure information may be limited.
• Partner with Engineering, Manufacturing, and Facilities to identify and implement effective engineering and process controls using the hierarchy of controls.
• Evaluate the effectiveness of ventilation, containment, and other exposure-control systems and provide technical recommendations for improvement.
• Provide industrial hygiene input during new equipment, material, process, and facility reviews to ensure occupational health considerations are incorporated early in design and implementation.
• Serve as a technical resource for respiratory protection, PPE selection, occupational exposure limits, noise and hearing conservation, non-ionizing radiation, and medical surveillance requirements.
• Apply and interpret applicable OSHA and Cal/OSHA requirements and recognized industrial hygiene standards and guidance, including ACGIH, NIOSH, ANSI, and AIHA practices, to establish technically sound exposure assessment and control strategies.
• Analyze and interpret exposure monitoring data, toxicological information, and occupational exposure limits to develop practical recommendations and communicate risk to employees and leadership.
• Develop industrial hygiene procedures, technical guidance, training, and employee communications supporting occupational health programs.
• Support investigations involving potential employee exposures, occupational health concerns, incidents, or abnormal operating conditions.
• Maintain industrial hygiene and employee exposure records in accordance with applicable regulatory and company requirements.
• Support broader site EHS programs and initiatives where industrial hygiene expertise is required .

Basic Qualifications

• Bachelor's degree in Industrial Hygiene, Occupational Health, Environmental Health, Chemistry, Chemical Engineering, Toxicology, or a related technical discipline.
• 3+ years of professional industrial hygiene experience in manufacturing, aerospace, defense, advanced materials, R&D, or another technically complex environment.
• Demonstrated experience conducting occupational exposure assessments and developing sampling strategies.
• Experience with industrial hygiene monitoring methods and equipment for chemical and physical hazards.
• Working knowledge of OSHA and Cal/OSHA occupational health requirements and recognized industrial hygiene practices.
• Experience interpreting occupational exposure limits, toxicological information, sampling data, and technical process information.
• Ability to evaluate workplace hazards and translate technical findings into practical exposure‑control recommendations.
• Strong technical writing, communication, analytical, and problem‑solving skills.
• Ability to work effectively with engineers, manufacturing personnel, technicians, and leadership in a fast‑paced environment.

Preferred Qualifications

• Master's degree in Industrial Hygiene, Occupational Health, Toxicology, or a related technical discipline.
• Certified Industrial Hygienist (CIH) credential or demonstrated progress toward certification.
• Experience in aerospace, defense, advanced manufacturing, composites/materials, or high‑tempo R&D environments.
• Experience evaluating ventilation, containment, and other engineering controls.
• Experience supporting respiratory protection, hearing conservation, and medical surveillance programs.
• Experience assessing occupational exposures involving advanced materials or processes where established exposure information may be limited.
• Experience developing or scaling industrial hygiene programs within a growing organization.

This position is primarily onsite and requires regular presence in manufacturing, laboratory, and R&D environments. The role may require the use of personal protective equipment and occasional work outside normal business hours to evaluate operations or processes.

Castelion offers a generous benefits package. Please refer to the bottom of our Careers page for more details.

Other Duties

Please note this job description is not designed to cover or contain a comprehensive listing of activities, duties or responsibilities that are required of the employee for this job. Duties, responsibilities and activities may change at any time with or without notice.

Additional Eligibility Requirements

This position may require access to classified information or restricted U.S. Government sites, systems, or information, as determined by the Company and/or applicable U.S. Government requirements. If the position is so designated, your employment in the role may be contingent upon your ability to obtain and maintain the required U.S. Government security clearance or other government authorization, and to satisfy any citizenship or other eligibility requirements imposed by applicable law, regulation, executive order, or government contract requirements. You will be notified if and when such requirements apply.

Affirmative Action/EEO Statement

Castelion is an Equal Opportunity Employer. We are committed to providing equal employment opportunities to all applicants and employees without regard to race, color, religion, sex, sexual orientation, gender identity, national origin, age, disability, genetic information, protected veteran status, or any other characteristic protected by applicable federal, state, or local law.

Castelion is committed to providing reasonable accommodations to qualified individuals with disabilities throughout the application and hiring process. If you require a reasonable accommodation to complete an application, participate in the interview process, or otherwise participate in the hiring process, please contact View email address on click.appcast.io. Requests for accommodation will be considered on an individual basis and handled in accordance with applicable law.

Castelion is committed to fostering a workplace where employment decisions are based on qualifications, business needs, and the ability to perform the essential functions of the role, with or without reasonable accommodation.

This position requires access to export-controlled information, and as such, employment (or hiring of a contractor) is contingent upon the candidate’s ability to access all applicable export-controlled information without additional export licensing being required by the Bureau of Industry and Security and/or the Directorate of Defense Trade Controls.