Therac-25 Case

 By Raul Bernardino

Nowadays, a computing took a biggest part of human life and almost given all kind of the possible solution the human kind issues that day to day they are facing. Even though not all ideas and concepts that the computing professionals put together to build the supercomputing is perfect or and work as it is expected to operate. The ideas to have the supercomputing is to help human to solve some necessary issues that human by himself cannot do it by manually. What I do mean by manual here is that human being just cannot do anything with it is own hand or event viewed by it is own eyes. He or she does need tools.  For instance skin laser surgeries or take out small tumor in site the some one ear without doing a big surgery. These all human needs a tool to help and solve issue with accuracy, effective, efficient, and safety.

The computing professionals have to responsible to the society of the implementation of the ideas and concepts that they are direct or indirect involved which is building of the tools. The computing professional must be in line with ACM and IEEE on code of ethic and professional code of conduct. To minimize the social impact we have to stick on our role and responsibility as computing professional.

The Therac-25 is one of example of the tools or machines in which that the computing professional built to help the society and implement in the hospitals for cancer therapies.  Therac-25 is a new generation of the therac-6 and therac-20 in which built by “Atomic Energy of Canada Limited (AECL)” and “CGR”. These machines were created to produce energy beam or radiation in which is to destroy tumors. Usually, the radiation therapies will be taking in place after the patient got a surgery. In this case the cancer patient who has got through a surgery and has been removed the major part of tumors by doctor. He or she has to do several therapies of treatments to proceed in order to kill any left growth cancer.

How Therac-25 operates? There are 2 types of the Therac-25 operations:

·       Low energy mode: in this mode patient is getting a direct radiation in which is using 200 rads

·      High energy mode: In this mode patient is using 25 millions electron volts through the plate or using full power of the machines

·    These two operations are controlled by software in which is the designer believes that is cost effective (-save money and time) and safety. Because the older machine like Therac-6 has different machines of controller to monitor the safeties.  

·      The software that used in Therac-25 come from Therac-6 and Therac-20

Incident: The incident happened in between1985 & 1987 in which were cost six persons lives including families and relative where lost their beloved one. Later it was discovered that there were a bug in therac-25 and therac-20 software.

Possible Thearac-25 Failures:

·        There were no proper assessment and testing of the new created machine

·        Error detection massage are not well design

·        Not proper action after first error detected

·        The safety glitch is not proper installed

·       There were not have a proper communication among hospital who using the machine with government and manufactory

How to overcome the situation: 

·      Any error happen must consult with the manual or the owner of coding software or manufactory before take any further actions.

·   Report the issue to the relevance body in this case institutions, government and manufacturer.

·  The computing professional responsibility to make sure all necessary tools that involves in his or her design must good assessment and well tested before fabricating. After it is being on production still do need a test for the quality and insurance before it apply or operate to human being.

  

References list:

·    Adams, A.A. & McCrindle, R.J. (2008) Pandora’s box: Social and professional issues of the information age. West Sussex, England: John Wiley & Sons, Ltd. Ch 10, P.323-332

·        The Therac-25 case study in the safety failure [on-line]. Available from: http://www.cs.jhu.edu/~cis/cista/445/Lectures/Therac.pdf  (Accessed date: January 21, 2011)

·        Case Analysis Module: Therac-25 [on-line]. Available from: http://cnx.org/content/m13765/latest/ (Accessed date: January 21, 2011)

·        Therac-25 Material 25 [on-line]. Available from: http://computingcases.org/case_materials/therac/therac_case_intro.html (Accessed date: January 21, 2011)

·        An Investigation of the Therac-25 Incident [on-line]. Available from: http://courses.cs.vt.edu/cs3604/lib/Therac_25/Therac_1.html (Accessed date: January 21, 2011)

·        A history of the introduction and shutdown of therac-25[on-line]. Available from: http://computingcases.org/case_materials/therac/case_history/Case%20History.html (Accessed date: January 21, 2011)

·        Using ImpactCS to grid understand Therac-25 [on-line]. Available from: http://computingcases.org/case_materials/therac/analysis/Intro_to_Analysis.html (Accessed date: January 21, 2011)

·        Computer society codes from around the world [on-line].Available from: http://courses.cs.vt.edu/~cs3604/lib/WorldCodes/WorldCodes.html (Accessed date: January 23, 2011)

·        ACM code of ethic and professional conduct [on-line].Available from: http://www.acm.org/about/code-of-ethics (Accessed date: January 23, 2011)