Objective Scientific

into the cause of fires, explosions, industrial accidents, electrocutions, and equipment failures.

About Us

When accidents or failures happen, the affected parties want to know how and why they occurred as these events often lead to the filing of an insurance claim or lawsuit. At Integrity Forensics & Engineering, LLC we specialize in failure analysis and forensic engineering. Our team of professional engineers and technical consultants is dedicated to a systematic, objective, scientific analysis of these claims, not only because we feel this is the most reliable approach, but because we believe that a true scientific understanding of how an accident or failure happened is the first step to empowering others to prevent them from happening in the future.

With over a century of collective forensic engineering experience, our professional engineers and technical consultants have a broad range of experience and expertise in analyzing failures from electrical and mechanical systems, to fires and explosions, to industrial accidents and electrocutions, to equipment damage and assessment. The professional engineers and consultants at Integrity Forensics & Engineering, LLC. understand the importance of maintaining an unbiased approach to investigating the cause of accidents and failures and have been qualified to provide expert witness testimony in their respective fields.

Integrity Forensics & Engineering, LLC. is able to provide consulting and technical services to clients in all 50 states and internationally.

Our Professionals

Mark Hergenrether, P.E.

Consulting Engineer

Mr. Hergenrether holds both a Bachelor of Science and a Master of Science in Mechanical Engineering from Oklahoma State University. He is a licensed professional engineer in multiple states and holds a NAFI certification as a Certified Fire and Explosion Investigator (CFEI).

Mr. Hergenrether has been active in forensic engineering and failure analysis since 2004. He specializes in investigating fires and explosions, industrial machinery and equipment accidents, analysis and testing of failures in mechanical and electrical systems, and investigating carbon monoxide incidents.

Mr. Hergenrether has provided expert testimony in multiple states and is a founder of Integrity Forensics & Engineering. LLC.

Tony Perryman, P.E.

Consulting Engineer

Mr. Perryman is a licensed professional engineer in multiple states with an extensive and diverse background in multiple areas of electrical construction, automotive, and heavy equipment. Mr. Perryman is also licensed as a NAFI Certified Fire and Explosion Investigator (CFEI), Certified Vehicle Fire Investigator (CVFI), and an electrician.

Mr. Perryman has been consulting throughout the United States and internationally in electrical engineering since 1999. Mr. Perryman’s expertise in electrical distribution systems and code compliance of these systems includes electrical service infrastructure, normal and emergency power systems, low voltage systems, fire alarm systems, vehicles, heavy machinery, and recreational vehicles.

Mr. Perryman has provided expert testimony in multiple states and is a founder of Integrity Forensics & Engineering, LLC.

Kelly Colwell

Technical Consultant

Mr. Colwell is a certified Master Electrician and brings over 20 years of experience in both residential and commercial construction. Since 2001, Mr. Colwell has investigated matters involving fires, electrocution or shock, failures of electrical systems and components, lightning related incidents, and analysis of electrical installations.

Mr. Colwell has provided presentations on fires and electrical accidents and has provided expert testimony in multiple states. In addition to his work in failure analysis, Mr. Colwell currently owns and manages an electrical contracting business operating in the North Texas area.

Mr. Colwell is one of the founders of Integrity Forensics & Engineering, LLC.

Johnie P. Spruiell, P.E.

Consulting Engineer

Mr. Spruiell holds a Bachelor of Science degree in Mechanical Engineering from the University of Texas at Arlington and is a licensed professional engineer in multiple states.

Mr. Spruiell’s practice in the field of forensic engineering began in 1981. His specialties include the investigation of fires and fuel gas explosions, determination of the causes of accidents and general product failures, evaluation of warning and guarding, evaluation of machine and system design, laboratory testing of products, high voltage testing, determination of the cause of carbon monoxide poisoning incidents, and evaluation of the cause of plumbing and plumbing component leakage incidents.

Mr. Spruiell has testified as an expert numerous times, both in depositions and at trial, in multiple states.

Shawn Thompson, P.E.

Consulting Engineer

Mr. Thompson is a licensed Professional Engineer in multiple states. He earned a Bachelor of Science in Mechanical Engineering from Oklahoma Christian University and spent a number of years in the commercial vehicle industry before entering the forensic engineering field in 2009. In addition to holding NAFI certifications as a Certified Fire and Explosion Investigator (CFEI) and as a Certified Vehicle Fire Investigator (CVFI), Mr. Thompson is also a F.I.R.E. Certified Fireplace And Chimney Investigator.

Mr. Thompson consults on investigations involving fires in vehicles, equipment, machinery, structures, explosions, accidents, product failures, and testing of mechanical and electrical components and systems.

Derek Geer, P.E.

Consulting Engineer

Mr. Geer graduated with honors in Electrical Engineering from the University of New Mexico and is a Senior Member of the Institute of Electrical and Electronics Engineering. He holds two patents in diverse fields and has been cited in Who’s Who in Science and Engineering. He has been certified as a Professional Engineer in both electrical and mechanical engineering in multiple states. He is certified by NAFI as both a Fire and Explosions Investigator (CFEI), as well as a Vehicle Fire Investigator (CVFI).

Mr. Geer has an extensive background in avionic, automotive and consumer electronics design. Failure analysis, quality control and design worst-casing are also specialties. He has been involved in extensive investigations into lightning related structural fires and lightning testing. He has valuable experience in the investigation and analysis of electromechanical and HVAC system failures.

Michael Shuttlesworth, P.E.

Consulting Engineer

Mr. Shuttlesworth graduated from Oklahoma Christian University with a Bachelor of Science in Mechanical Engineering. He is a licensed professional engineer with experience in failure analysis, destructive and non-destructive testing methods, and forensic lab management and operation.

Mr. Shuttlesworth has been consulting as a forensic engineer since 2011 and has experience in plumbing systems, piping, and appliance component failures. He has designed, constructed, and directly tested a variety of products or components to access failure modes. Mr. Shuttlesworth also has experience in evidence collection, documentation, and preservation.

Our Facilities

We are conveniently located just north of the Dallas-Fort Worth Metroplex in Sanger, Texas. Our primary research complex includes our consulting offices, laboratory inspection areas, high-voltage testing laboratory, a 10,000 pound vehicle lift and inspection area, 1,500 feet of indoor evidence storage, and a secured outdoor storage yard with video surveillance. Our overflow storage warehouse for long-term evidence preservation is only a short, eight-minute drive from our main facility, and we can easily retrieve evidence when it is needed.

We understand that every case is unique. To better assist you, we have designed our facilities so that we can offer a customized approach to meet your needs for testing and analysis. Please contact us to see how we can best be of service to you.



Electrical & Mechanical Engineering Consulting

Our engineers are experienced in the evaluation of fires and explosions, commercial and industrial electrical service, power generation and distribution systems, lightning damage, fire alarms and suppression systems, heavy machinery and equipment, plumbing and gas systems, HVAC, vehicles, and recreational equipment.

High-Voltage Facilities

In our high voltage lab, we can perform high voltage impulse testing, various insulation and dielectric strength tests, and testing of CSST (corrugated stainless steel tubing) and radiant barrier products. Our 1,500 square foot testing lab is large enough to allow for a customized setup depending on your component or product needs.

Laboratory Services

Our laboratory serves to facilitate an assortment of destructive and non-destructive examinations, from microscopic inspections to the tear-down of large industrial equipment. We offer scanning electron microscopy with elemental analysis and host third-party laboratory examinations upon request.

Testing Services

We provide a broad range of electrical/mechanical product and component testing, fuel gas system and equipment testing, customized large- and small-scale mock-up testing, fireplace systems, radiography (x-ray services), and thermal imaging services.

Evidence Storage

Our secured evidence storage facilities can manage both large and small evidence storage needs, monitored by video 24 hours a day. We offer short- and long-term storage solutions based on your storage needs.

Litigation Support

Our experts are trained, experienced, and qualified in the field of forensic engineering. We help you complete document review, prepare trial mockups, and provide expert witness testimony.

Contact Us

If you would like to request our assistance in performing a technical and or research investigation, please send us your request using this form, or contact one of our engineers or consultants directly via email.

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