CS 4970 Writing Assignment #1
Instructor: K.
Palaniappan
First draft due XXX,
In-class discussion of your first draft XXX
Final draft due XXX+one week
Applied Ethics in Professional Engineering
The issues raised in the Therac-25 case study are quite general and applicable to your professional career. A synopsis of the case study is given in the last section of the web page below. A more specific description of the assignment is given in the following Word file: WI-1_Ethics_CS4970.doc
Short description at National Academy of Engineering: http://www.onlineethics.org/CMS/computers/compcases/therac25.aspx
The Therac-25 case materials in much greater detail are located at: http://computingcases.org/case_materials/therac/therac_case_intro.html
An extensive article by Prof. Nancy Leveson (MIT) abstracted with permission from her textbook can be downloaded: Medical Devices - The Therac-25
First read the case (both the synopsis and detailed case materials) and understand the complex issues involving various parties including corporate, government, patient and various components including engineering, management, regulatory, socio-technical and ethical. Second decide what are the major issues surrounding the defects in the Therac-25 equipment function.
Read and understand in detail one of the complete NSPE, ACM and IEEE codes of ethics which are summarized in list form below. The more complete explanation of each of the codes of conduct can be found in the respective web links given below.
Write an essay describing how ethical lapses contributed to the overdosing problem and the protracted time period needed to identify and correct the Therac-25 radiation therapy equipment defects. Describe your actions, as an engineer, in coming to grips with the Therac-25 malfunction, utilizing one of the NSPE, ACM and IEEE codes of ethics as a guide in influencing or determining your course of action. Describe the advantages and disadvantages of your decision. That is describe the advantages and disadvantages of the actions you propose and provide justification using one of the codes of ethics as a guideline in the analysis process.
You will be required to submit a draft that outlines your position which will be reviewed and graded. You will then revise and expand your essay and submit a final version. You should have at least five pages.
http://www.onlineethics.org/codes/NSPEcode.html
Engineers, in the fulfillment of their professional duties, shall:
1. Hold paramount the safety, health and welfare of the public.
2. Perform services only in areas of their competence.
3. Issue public statements only in an objective and truthful manner.
4. Act for each employer or client as faithful agents or trustees.
5. Avoid deceptive acts.
6. Conduct themselves honorably, responsibly, ethically and lawfully so as to enhance the honor, reputation and usefulness of the profession.
http://www.acm.org/constitution/code.html, http://www.onlineethics.org/codes/softeng.html
Standard for teaching and practicing software engineering as recommended by the IEEE-CS/ACM Joint Task Force on Software Engineering Ethics and Professional Practices and Jointly approved by the ACM and the IEEE-CS. (Version 5.2)
Software Engineering Code of Ethics and Professional Practice Software engineers shall commit themselves to making the analysis, specification, design, development, testing and maintenance of software a beneficial and respected profession. In accordance with their commitment to the health, safety and welfare of the public, software engineers shall adhere to the following Eight Principles:
1. PUBLIC - Software engineers shall act consistently with the public interest.
2. CLIENT AND EMPLOYER - Software engineers shall act in a manner that is in the best interests of their client and employer consistent with the public interest.
3. PRODUCT - Software engineers shall ensure that their products and related modifications meet the highest professional standards possible.
4. JUDGMENT - Software engineers shall maintain integrity and independence in their professional judgment.
5. MANAGEMENT - Software engineering managers and leaders shall subscribe to and promote an ethical approach to the management of software development and maintenance.
6. PROFESSION - Software engineers shall advance the integrity and reputation of the profession consistent with the public interest.
7. COLLEAGUES - Software engineers shall be fair to and supportive of their colleagues.
8. SELF - Software engineers shall participate in lifelong learning regarding the practice of their profession and shall promote an ethical approach to the practice of the profession.
http://www.ieeeusa.org/DOCUMENTS/CAREER/CAREER_LIBRARY/ethics.html
We, the members of the IEEE, in recognition of the importance of our technologies in affecting the quality of life throughout the world, and in accepting a personal obligation to our profession, its members and the communities we serve, do hereby commit ourselves to the highest ethical and professional conduct and agree:
1. to accept responsibility in making engineering decisions consistent with the safety, health and welfare of the public, and to disclose promptly factors that might endanger the public or the environment;
2. to avoid real or perceived conflicts of interest whenever possible, and to disclose them to affected parties when they do exist;
3. to be honest and realistic in stating claims or estimates based on available data;
4. to reject bribery in all its forms;
5. to improve the understanding of technology, its appropriate application, and potential consequences;
6. to maintain and improve our technical competence and to undertake technological tasks for others only if qualified by training or experience, or after full disclosure of pertinent limitations;
7. to seek, accept, and offer honest criticism of technical work, to acknowledge and correct errors, and to credit properly the contributions of others;
8. to treat fairly all persons regardless of such factors as race, religion, gender, disability, age, or national origin;
9. to avoid injuring others, their property, reputation, or employment by false or malicious action;
10. to assist colleagues and co-workers in their professional development and to support them in following this code of ethics.
by Nancy G. Leveson, University of Washington, and
Clark S. Turner, University of California, Irvine
abstracted by Philip D. Sarin, MIT '99
The Therac-25, a computerized radiation therapy machine, massively overdosed patients at least six times between June 1985 and January 1987. Each overdose was several times the normal therapeutic dose and resulted in the patient's severe injury or even death. Overdoses, although they sometimes involved operator error, occurred primarily because of errors in the Therac-25's software and because the manufacturer did not follow proper software engineering practices.
Overconfidence in the ability of software to ensure the safety of the Therac-25 was an important factor which led to the accidents. The Therac-20, a predecessor of the Therac-25, employed independent protective circuits and mechanical interlocks to protect against overdose. The Therac-25 relied more heavily on software. Moreoever, when the manufacturer started receiving accident reports, it, unable to reproduce the accidents, assumed hardware faults, implemented minor fixes, and then declared that the machine's safety had improved by several orders of magnitude.
The design of the software was itself unsafe. The Therac-25 supported a multitasking environment, and the software allowed concurrent access to shared data. This precarious implementation caused program failure under certain conditions.
Risk assessments were, from the start, unrealistic. A risk assessment performed by the manufacturer seems to consider only hardware failures as it lists the possibilities of the computer selecting the wrong energy or mode as 1e-11 and 4e-9 respectively. Justification never appears for these numbers, but, more surprisingly, the company accepted this low risk assessment easily.
Follow-through on accident reports was unacceptable. After one accident, the manufacturer tried to reproduce the condition which occurred at the treatment. When it could not, it concluded that a hardware error caused the accident, and implemented a solution based on that assumption. It declared that the system was several orders of magnitude safer, but accidents did not cease.
The Therac-25 incidents demonstrate that several misconceptions in the manufacturer's attitude led to the accidents. Poor software design, overconfidence in the software's abilities, unreasonably low risk assessments, and poor manufacturer response to complaints all contributed to the overdoses. Companies must understand that for safety-critical software design rigorous testing and failure analyses are essential and that trained software engineers, not simply any reasonably experienced engineers, should implement the software design.
Guidelines for Writing the Essay
Please take the following points into consideration when writing your 2nd draft:
Style and Organization
à Interesting title
à Case background, introduction, summary
à Identify the problems / issues that may be attributed to organizational, procedural, governmental, technical, ethical etc. flaws or deficiencies.
à Course of action / steps you would take as an engineer in the employment of the company and its justification in terms of ethical and engineering guidelines. The temporal point is before product release or during the accident period. (You may provide a first – person perspective for this part of the essay, if you wish).
à References (IEEE style, ACM style etc)
A few examples are given below: (The IEEE style is preferred, but not mandatory)
Research paper references:
Steven Parker, Peter Shirley, Yarden Livnat, Charles Hansen, and Peter Pike Sloan. Interactive ray tracing for isosurface rendering. In IEEE Visualization ’98, pages 233 – 238, October 1998.
Textbook references:
Christophe Schlick. High dynamic range pixels. Graphics Gems, 4:422 – 429, 1994.
Web page references:
Alias Wavefront. Maya. http://www.aliaswavefront.com
For more examples, refer to the ‘References’ section of any paper that has been published in an IEEE / ACM journal – these follow the respective reference styles.
à Spelling, grammar
à Use a formal style when writing your essay.