Radioactive Materials Expert Witnesses

Scott L. Turner is a highly qualified Commercial Motor Vehicle (CMV) Transportation Expert, FMCSR Regulatory and PHMSA-HMR Expert with approximately 30-years experience in the highly specialized field of CMV crashes and incidents, and 16 years as the CEO of a nationwide CMV crash & HazMat disaster response corporation. 

Mr. Turner's career includes personal response and/or investigation of over 1,000 CMV crashes, 200 cargo-tank truck crashes/incidents and a multitude of industrial setting incidents including fixed facilities, loading docks and loading rack disasters. His FMCSR and PHMSA knowledge (Federal Enforcement Training), detailed reporting and testimony can be a focal point of any civil litigation, where commercial motor vehicle crashes and/or transit incidents are at issue, with or without hazmat involvement. Mr. Turner is qualified in both the Federal Court system as well as multiple States throughout the United States and testifies on an approximate 50/50 average of Defense to Plaintiff ratio.

Areas of Expertise:

• Level 1 FMCSA Inspections
• Commercial Motor Vehicle (CMV) Post-Crash Inspection
• CMV Post-Crash Investigation
• Driver Qualifications
• HOS / Fatigue Driving
• Motor Carrier Fitness Standards
• Safety Programs
• Trucking Industry Standards
• Cargo-Tank Truck Incidents / Crashes
• CMV loading/Off-loading Cases (van, cargo-tank, flatbed)
• Flatbed, Cargo Securement Failure
• Loading Dock Incidents w/ CMV
• Forklift Incidents w/ CMV
• CMV Crash Involving Hazmats
• Loading Rack Explosions / Disasters
• Pedestrian v. CMV Incidents

Services Include:

• Litigation Support
• Trial Preparation Consulting
• Courtroom Testimony
• Commerical Vehicle Accident Investigations
• CMV, Highway Construction Zone Crashes
• CMV Loading and Offloading Investigation
• Level 1 FMCSA Audits
• Load Securement Incidents

I bring diverse, combined education, licensing, and credentialing in geology, biology, and hazardous materials management. Indoor air quality as related to asbestos, mold, lead, building hazards, vapor intrusion, OSHA worker and occupant complaints.

I manage a firm of environmental and industrial hygiene professionals while serving as an expert in my diverse field; I have over 85 retained cases complete. I can cost effectively support engagements that may require extensive data gathering across an expanded time frame. I apply my capabilities and credentials across commercial, industrial, and oil & gas settings, with a technical focus on highly regulated industry and real estate.

I have been steadily retained for expert witness services since 1995.

I specialize in structural fire forensic investigation and testing, routinely leverage post-flood emergency response expertise in buildings, specific to microbial disinfection, mold mitigation, and source mold under forensic methods of investigation that may exist under alleged building construction defects. I possess expertise in building systems and mitigating hazards from structures in advance of demolition for asbestos, lead, and other regulated materials.  I prepare, implement (and/or critically review) asbestos specifications, mold remediation protocols, OSHA-driven lead specifications, and remediation soil management plans.

I have evaluated diverse workplaces following loss reports due to alleged safety and public health concerns and offered mitigation strategies for worker safety under OSHA complaints, especially regarding respiratory protection. I have served as an expert for multiple worker injury and wrongful death allegations within the context of environmental exposure.  

View Ms. Franks' Consulting Profile.

Professor Christopher J. Tennant, PhD, CIH, has over 40 years of experience in the field of Environmental Health and Industrial Hygiene. He is Board Certified in the Comprehensive Practice of Industrial Hygiene. Dr. Tennant is currently President, CEO, and Principal Consultant at San Joaquin Environmental, in Fresno California, where he consults with Federal, State, County, City, various public agencies, and private industry sectors from public housing to Aerospace. His services are available in all 50 US States and the United Kingdom.

Dr. Tennant also serves as Professor Emeritus for the Department of Public Health at Fresno State University where he's taught Environment Health, Industrial Hygiene, and Occupational Health and Safety for 35 years at both undergraduate and post graduate levels.

Litigation Support - Dr. Tennant has been retained by numerous insurances companies and law firms on various Industrial Hygiene matters throughout the US, including workers compensation, property damage, personal injury, and wrongful death. He has testified as an expert witness in Federal Court, Superior Court, and Workers Compensation Appeals Board over 100 times. He's been deposed many more times. 

Areas of Expertise:

Paul E. Rosenfeld, M.S., Ph.D., is the Founder and Principal Scientist of RoseyFields LLC and a nationally recognized forensic environmental scientist and plaintiff expert witness. Over 25 years, his work has spanned complex toxic-tort and class-action litigation — including MTBE, PFOA/PFAS, asbestos, FELA railroad exposure, air-dispersion modeling, epidemiology, toxicology, industrial contamination, and pesticide exposure matters — with an aggregate case value of approximately $14 billion, and he has been deposed approximately 150 times in 31 states.

Litigation Support

Dr. Rosenfeld's opinions are based on established scientific methodologies, quantitative exposure models, peer-reviewed scientific literature, published technical methods, and reproducible calculations that can be independently evaluated and tested, providing a rigorous scientific foundation for expert opinions under Daubert and related standards for the admissibility of scientific evidence. He has authored and contributed to books and technical publications concerning environmental contamination, exposure assessment, and risk evaluation and has applied these scientific methods in expert reports, litigation, depositions, regulatory proceedings, and trial testimony.

Methodologies & Scientific Approach

Dr. Rosenfeld's air dispersion modeling work applies EPA-approved and peer-reviewed models, including AERMOD, CALPUFF, and ALOHA, to reconstruct historical emissions, source attribution, and community-level exposure pathways. His exposure and dose reconstruction methods integrate environmental sampling data, regulatory exposure factors, and published toxicological and epidemiological literature to quantify human exposure to chemicals including benzene, PFAS/PFOA, TCE, hexavalent chromium, and crystalline silica, among others. Each methodology is applied transparently, allowing the underlying calculations, data inputs, and modeling assumptions to support general cuasation opinions. 

Publications & Court Qualifications

Dr. Rosenfeld has authored six books and dozens of peer-reviewed publications on environmental contamination and risk assessment. He has been qualified as an expert under Daubert and analogous standards in federal and state courts nationwide reflecting consistent application of scientifically defensible methodologies under prevailing standards for expert testimony admissibility.

Areas of Expertise:

Mark O. Barnett, PhD, PE, BCEE has over 30 years of national and international Environmental Engineering and Science experience in industry, government, and academia ranging from water supply and sanitation in rural communities to nuclear waste disposal. He is currently a Professor of Environmental Engineering in the Department of Civil and Environmental Engineering at Auburn University.

Litigation Support - Dr. Barnett has served as an environmental expert witness-expert consultant on cases in administrative, federal, and state courts ranging from permit applications to toxic tort lawsuits. He has written expert reports, filed affidavits, been deposed, and given testimony. Further, he has extensive litigation experience from his service as an administrative judge with the Nuclear Regulatory Commission. Writing samples, transcripts, and references are available upon request.

Areas of Expertise:

Background Experience - Dr. Barnett is a licensed professional engineer and a board-certified member of the American Academy of Environmental Engineers and Scientists. His technical research focuses on the chemical processes controlling water quality and contaminant behavior in natural and engineered systems. He has been a principal or co-principal investigator on seventeen grants totaling over $12 million, and he has published over fifty peer-reviewed journal articles, several book chapters, and a book that collectively have received over three-thousand citations.

Dr. Barnett has a B.S. in Chemical Engineering and an M.S. in Environmental Engineering from the University of Tennessee and a Ph.D. in Environmental Sciences and Engineering from the University of North Carolina. He has taught fundamental and applied courses in environmental and aquatic chemistry; water and wastewater treatment; environmental engineering principles and design; and sustainable design and development.

Rudolph Johnson, PhD, is a Chemical Toxicologist with over 20 years of experience in analytical chemistry and toxicological investigations. Dr. Johnson's past experience includes directing the (1) clinical toxicology network, LRN-C, at the Centers for Disease Control and Prevention and (2) the Military Exposures Research Program at the US Department of Veterans Affairs. Currently, he serves as the Director of the Wisconsin State Laboratory of Hygiene and has a faculty appointment at the University of Wisconsin-Madison School of Medicine and Public Health, Department of Pathology.

Dr. Johnson focuses on two specialty areas:

(A) Toxicology: He offers causation opinions connecting dose, analytical detection, and biomarker findings to determine whether and to what extent an individual was exposed to a chemical or toxin.  The chemical or toxin may be inhaled, ingested or injected. This includes drug and alcohol testing.

(B) Laboratory Testing: He critiques or defends laboratory testing methodology, chain-of-custody, and quality assurance practices. He is an expert at evaluating conflicting testing data between two labs.

Litigation Support - Dr. Johnson works with plaintiff and defense litigation attorneys on toxic tort, product liability, and environmental and occupational exposure cases requiring causation analysis. He supports criminal defense and plaintiffs reviewing drug exposures (opioids, fentanyl analogs, polypharmacy) and alcohol testing. This includes chain-of-custody, and quality practices. Conflicting or inconsistent laboratory data, especially between multiple laboratories, is a specialty area of Dr. Johnson because he previously directed multiple clinical toxicology labs.

Dr. Johnson detects, quantifies, and interprets chemical and toxic exposure in human clinical samples. He is skilled in translating investigative information into causation opinions, connecting dose, biomarker significance, and clinical outcome—for poisoning, occupational, environmental, and mass-casualty toxicology cases.

Areas of Expertise:

DNA Industrial Hygiene CSLB 773462 1A,HAZ is an occupational/environmental health & safety firm providing comprehensive industrial hygiene/environmental services. Dan Napier is the 'go to' person for help with your health & safety program. if you are a small business or one of the fortune 500's DNA has helped someone like you. whether you need a simple survey for a single issue or a complex benchmark or safety audit they have the experience and expertise to do the work. Mr. Napier provides services to the legal community. please check with him for trial assistance, forensic studies or expert witness services. he has been designated as an expert and has testified in federal and state courts.

Jorge Vizcaino, CHMM, CIH, CAC, CDPH Lead Inspector/Assessor, is a Certified Asbestos Consultant (CAC) and Certified Industrial Hygienist (CIH). He has over 26 years of experience in Industrial Hygiene Safety, Hazardous Material Assessments, Indoor Air Quality. He is an active member of the American Industrial Hygiene Association. 

Litigation Support - Jorge Vizcaino has over 23 years of experience working with the legal industry. His services are available to attorneys representing Plaintiff and Defense. Mr. Vizcaino has testified in over 30 legal cases. 

Areas of Expertise:

Background - Mr. Vizcaino is a Certified Industrial Hygienist (CIH), Certified Hazardous Materials Manager (CHMM), and California Certified Asbestos Consultant (CAC), with extensive expertise in hazardous materials, chemical exposure assessment, indoor air quality, environmental remediation, and occupational health and safety compliance. Mr. Vizcaino specializes in industrial chemical exposure assessments, crystalline silica and noise monitoring, hazardous waste characterization (TCLP, TTLC, WET), asbestos and lead abatement oversight, and emergency response for hazardous releases. He has developed and implemented site-specific health and safety plans (SSHASP), negotiated regulatory compliance actions, and provided strategic environmental guidance to senior management teams regarding operational risk and capital projects. 

In addition to his consulting work, Mr. Vizcaino has extensive experience as an expert witness in toxic tort, microbial contamination, asbestos/lead exposure, catastrophic fire, and carbon monoxide cases. He has participated in depositions, regulatory negotiations, and courtroom testimony in both plaintiff and defense matters.

911 Consulting specializes in Emergency Preparedness, Training, Drills and Exercises for corporations, campuses and medical facilities. 911 Consulting offers practical solutions for preventing likely incidents, preparing for emergencies, responding to a crisis, and resuming operations. They create a custom emergency plan, train personnel, and stage drills for readiness.

Bo Mitchell was Police Commissioner of Wilton, CT for 16 years. He retired to found 911 Consulting which creates emergency, disaster recovery, business continuity, crisis communications and pandemic plans, plus training and exercise for organizations like GE HQ, Hyatt HQ, MasterCard HQ, five colleges and universities plus 29 PreK-12 schools.

Bo serves clients headquartered from Boston to LA working in their facilities from London to San Francisco. He has earned 23 certifications in homeland security, emergency management, disaster recovery, business continuity, safety and security. Mission: Trying to make America safer one workplace at a time.

Litigation Support - Bo serves as an expert in landmark court cases nationally.  He provides expert witness services to attorneys representing plaintiff and defense, including thorough reporting, depositions, and trial testimony as needed.

Areas of Expertise: 

Professional Designations: CEM, CPP, CHS-V, CBCP, CSI-ML, HSEEP, CSSAS, CNTA, IAC, MOAB, CHSP, CHEP, CSHM, CESCO, CHCM, CFC, CSSM, CSC, CAS, TFCT3, CERT, CHSEMR, CMC