In April, 1995, Purdue University's School of Technology approved a new graduate course entitled Applications in Forensic Engineering Technology. The course was offered for the first time in the spring of 1996 under the provisional designation of TECH 581E. Response was strong, with 23 students completing the course. The interdisciplinary nature of the course resulted in a diverse class. Of the 23 students in the class, 11 had an electrical background, six had a mechanical background, four had an aviation background, and two had a general technology background. Topics included failure analysis of electrical and mechanical systems, evidence collection and handling, development of failure hypotheses, levels of confidence, forensic engineering reports, the legal process, expert witness testimony, fire science, explosion dynamics, and use of x-rays for non-destructive testing. Case studies were used extensively. Although the course was designed as a graduate elective for Master of Science students in the School of Technology, the course is also available to qualified and mature seniors in the various departments of the School of Technology as an interdisciplinary elective. The course was offered a second time in the spring of 1997. This paper will describe the conceptualization, design, development, and delivery of the course. Lessons learned from the first and second course offerings will be presented.

INTRODUCTION

Everything in our modern world is expected to operate as designed. But, when something goes wrong, we are reminded that things do not operate continually or forever. Failure of an engineered system may range from something spectacular like a structural collapse, to something relatively simple such as a leaky roof. Failures are investigated to enable a proper repair, to avoid repeating the mistake that led to the failure, and to identify the responsible parties. Identification of responsible parties is not to assign culpability, but to determine if the failure is related to design, construction, maintenance, or other condition. [1]

In order to learn from failures, it is necessary to study failures and failure investigation. The engineering discipline that deals with the investigation of failures and performance problems is called forensic engineering. Since failures may result in injury, death, or property damage, forensic engineers may have to testify in a legal proceeding.

The primary goal of TECH 581E is not to train forensic engineers, but to introduce engineering and technology students to the complex relationship between technology and the American legal system. The course will also help students develop their problem-solving and analytical skills through application of the scientific method to the many real-world cases studied.

FORENSIC ENGINEERING [1]

Forensic engineering can be defined as the application of the engineering sciences to the investigation of failures or other performance problems. Some forensic engineering projects or cases require sworn testimony in a court of law or legal proceeding. Thus, forensic engineers must work in both engineering and legal domains. From an engineering perspective, forensic engineering deals with the investigation and reconstruction of failures in buildings, structures, facilities, and other engineered systems. From a legal perspective, forensic engineering is a fact-finding mission to determine the most probable cause or causes of a failure and the party or parties responsible. Forensic engineering requires both scientific skills and high ethical standards. Forensic engineers must be expert in their field and impartial in the investigation process.

ACADEMIC LEVEL OF TECH 581E

The ideal student for this course is a mechanical or electrical engineer or technologist with several years of professional work experience. However, work experience was not made a prerequisite for the course. Nor is the course limited to the mechanical and electrical disciplines. Students with undergraduate degrees in engineering or engineering technology have the required scientific and technical background to handle the demands of this course. The course is also available to qualified and mature seniors in the various departments of the School of Technology as an interdisciplinary technical elective.

TEXTBOOKS

Two textbooks were selected for the first and second course offerings. They are Guidelines for Failure Investigation, published by the American Society of Civil Engineers (ASCE) and NFPA 921, Guide for Fire and Explosion Investigations, published by the National Fire Protection Association (NFPA).

ASCE's Guidelines for Failure Investigation was selected to introduce the students to forensic engineering, and to teach them how to properly conduct a forensic engineering investigation. It was also used as a guide in our study of the legal process, forensic engineering reports, ethical practice, and application of the scientific method.

NFPA 921, Guide for Fire and Explosion Investigations, is used in a more specialized sense. Many forensic engineers are involved in fire-related or explosion-related failure analysis. Some serve only as specialists, leaving the origin and cause determination to others. For example, an electrical engineer may specialize in fires of an electrical origin, while a mechanical engineer may specialize in gas fires and explosions. Some forensic engineers also conduct origin and cause investigations. NFPA 921 is used as a guide for the proper conduct of fire and explosion investigations. It is also used as a reference for the study of fire science, explosion dynamics, fire patterns, scene safety, origin and cause determination, electrical ignition, appliances, and application of the scientific method.

ASCE's Guidelines for Failure Investigation

Although Guidelines for Failure Investigation deals specifically with civil and structural failures, the guidance provided should also be applicable to other types of failures. In other words, it should be possible to apply the science and fundamentals of failure analysis to any type of failure. Chapter 2 in Guidelines for Failure Investigation states that these concepts may be used to prepare studies for situations in other engineering disciplines that require techniques for investigation, analysis, development of conclusions, and preparation of comprehensive reports suitable as a legal instrument. [1]

NFPA 921, Guide for Fire and Explosion Investigations [2] [3]

The NFPA Technical Committee on Investigation of Fires of Electrical Origin was formed in 1977. This committee was charged with the responsibility of developing a manual for the investigation of fires of electrical origin. This committee was discharged in 1984 when the new Technical Committee on Fire Investigations was formed. The new committee inherited the work of the original committee and developed NFPA 907M entitled Manual for the Determination of Electrical Fire Causes. NFPA 907M was published in 1988.

Upon completion of NFPA 907M, the committee began work on a new document designated as NFPA 921. The purpose of the new document was to establish guidelines and recommended practice for the safe and systematic investigation and analysis of fires and explosions. The first edition of NFPA 921, published in 1992, focused primarily on origin and cause determination involving structures only. The second edition, published in 1995, expanded the scope of the first edition. One major change to the document was the revision, expansion, and incorporation of NFPA 907M into NFPA 921.

NFPA 921 is not an engineering document per se. It is, however, a very technical document based upon accepted scientific and engineering principles. It contains practical investigation guidelines and is a consensus document published by an internationally-recognized fire standards organization. Although NFPA 921 does not carry the weight of a code or standard, it will likely be used in court as the accepted method of conducting fire or explosion investigations. In litigation terminology, NFPA 921 is treated as an authoritative treatise, and is fast becoming one of the most recognized authorities in the fire investigation field. [4]

OUTSIDE REFERENCES

The interdisciplinary nature of TECH 581E requires the use of many outside references. Selected papers and standards from a variety of sources, shown in tables 1 through 3, were made available for student use. Other references included industry standards applicable to mechanical and electrical systems, such as the National Fuel Gas Code, the National Electrical Code, and the National Electrical Safety Code. Legal references included the Reference Manual on Scientific Evidence [5] and the Federal Rules of Evidence. [6]

CASE STUDIES

Case studies from the course coordinators' professional experiences are used extensively in TECH 581E. In some instances, failed equipment from actual cases is brought to class for first hand observation and analysis. Recent and current forensic engineering investigations conducted by the NFPA and the National Transportation Safety Board (NTSB) are also studied. Reports of these investigations are often available on the world wide web. Two such cases studied were items 1 and 9 in table 2.

Guest lecturers make significant contributions to the course. They provide additional case studies and expand the interdisciplinary nature of the course. Five guest lecturers were invited to speak to the class over two years. The lecturers included academics and practitioners, all with experience in forensic engineering.

HAZARD and FPETOOL, the fire modeling software developed by the National Institute for Standards and Technology (NIST), were introduced in the initial course. FPETOOL was demonstrated. A copy of FASTLite, the most recent software release from NIST, was given to each student in the second course. NIST donated 40 copies of FASTLite to the class. Future use of 3D-STUDIO, the animation software from Autodesk, is being considered.

ASSIGNMENTS AND GRADING

There are 14 weekly assignments, each valued at 100 points, about 78% of the student's final grade. The weekly assignments require extensive reading and research of the texts and references. The final exam is the only formal examination in the course. It is valued at 200 points, about 11% of the final grade. The final examination is comprehensive. Most exam material is taken from the reading list and in-class presentations and discussions. A paper is also required. It is valued at 200 points, about 11% of the final grade. Students are required to select a topic of interest, which is also related to forensic engineering, and write a paper. Formal abstracts are required and must be approved by the course coordinator. Papers are critically reviewed in accordance with the following criteria: originality, data collection, analysis, testing, literature search, format, grammar, scholarship, use of references, conclusions, and interest to the class. Collaboration among students is encouraged. In the first course, two students attended a local trial that involved the testimony of an expert witness. They compared aspects of the trial with material learned in class and wrote an excellent paper about their experience. Another student designed an experiment to determine if damaged electrical cable can result in a fire. He was able to demonstrate flaming combustion under certain conditions.

TRIAL RUN

Table 4 lists the current course outline for TECH 581E. During October 1995, a series of four lectures on forensic engineering was presented by the course coordinator to the Institute of Electrical and Electronic Engineers (IEEE) Power Engineering Society in Indianapolis, IN. Approximately 35 to 45 electrical engineers attended the lecture series. This activity provided the course coordinator a unique opportunity to assess interest in the subject among practicing engineers and to test some of the lecture material developed for the graduate course. Since the attendees were electrical engineers, the scope was limited to topics of an electrical nature.

INTERNATIONAL ISSUES

In March 1996, the course coordinator had the unique opportunity to present a paper about the course at an international fire science and engineering conference in Cambridge, England. [8] He subsequently received a Global Initiative Faculty Grant from Purdue University to develop an international element for the course. This was implemented during the summer 1996. The international element consists of lecture, reading, and assigned

material in international standards and case studies. Much of the material came from the Interflam 96 conference proceedings.

CONCLUSIONS AND LESSONS LEARNED

1. With 35 students currently enrolled in the second course, student interest remains strong.
2. The interdisciplinary nature of the course is an advantage. It permits electrical, mechanical, and other engineering and technology disciplines to participate in the course.
3. The interdisciplinary nature of the course can sometimes be a disadvantage. Occasionally, the course coordinator must limit the technical scope of the subject matter at hand because everyone in the class may not have had the necessary prerequisite.
4. The donated FASTLite software is a valuable tool. Since the students can install it on their own computers, it can be used for out-of-class assignments. They can start by modeling simple building fires, and then progress to more complex applications, such as item 3 in table 2.
5. The INTERNET is a valuable resource. In addition to the case studies from NFPA and NTSB, the course coordinator used a web site to list weekly assignments and disseminate class information.
6. Accident prevention is emphasized. Many case studies include a discussion of how the incident could have been prevented.
7. The course coordinator continues to update and improve the course. A study of surface analysis techniques, such as electron spectroscopy for chemical analysis and auger electron spectroscopy, for the examination of electric arc residues is planned for the next course offering. [13]

REFERENCES

1. Greenspan, H.F., O'Kon, J.A., Kimball, J.B., and Ward, J.S. (1989). Guidelines for Failure Investigation. American Society of Civil Engineers, New York, NY.

2. National Fire Protection Association. (1992). Guide for Fire and Explosion Investigations (NFPA 921-92). Quincy, MA: NFPA.

3. National Fire Protection Association. (1995). Guide for Fire and Explosion Investigations (NFPA 921-95). Quincy, MA: NFPA.

4. Hewitt, T.D. (1996). Fire Litigation: The Role of NFPA 921. NFPA Journal, (pp. 40-43). Quincy, MA.

5. Reference Manual on Scientific Evidence, Federal Judicial Center. (1994). McGraw-Hill Book Company, New York.

6. The Federal Rules of Evidence.

7. DeWitt, W. E. (1994). An Engineering Review of NFPA Standard 921. Journal of the National Academy of Forensic Engineers, 11(2), 1-7, Hawthorn, NY.

8. DeWitt, W.E. (1996). Teaching Fire-Related Failure Analysis in a Post Graduate Course for Engineers and Technologists. Interflam '96, Seventh International Fire Science and Engineering Conference Proceedings (pp. 989 - 993). St. Johns College, Cambridge, England.

9. National Fire Protection Association. (1988). Manual for the Determination of Electrical Fire Causes (NFPA 907M). Quincy, MA: NFPA.

10. Shanley, J. H. (1992). The Future of Fire Investigation: NFPA 921 Guide for Fire and Explosion Investigations. Fire and Arson Investigator, St. Louis, MO.

11. Kennedy, P. M. (1991). Common Fire Investigation Misconceptions. The National Fire Investigator, Hoffman Estates, IL.

12. Custer, R. L. P. (1992). Open Letter, The National Fire Investigator, Hoffman Estates, IL.

13. Anderson, R. N. (1989). Surface Analysis of Electrical Arc Residues in Fire Investigation. Journal of Forensic Sciences, American Society for Testing and Materials, West Conshohocken, PA.

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