Journal of System Safety
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Principles Again
Get PDFoai:ojs2.jsystemsafety.com:article/2Do we have a “nearly perfect” book that covers the subject of system safety? If this book did exist, how would we know?
During a recent Zoom meeting on the International System Safety Society (ISSS) initiatives, I noted a few remarks of interest. One individual asked, “What is the gospel of system safety?” Later, they changed the question to one about “principles of system safety.” I was pleased to hear this, as it correlated with the point I was trying to make in my “From the Editor’s Desk” article on principles in the Fall/Winter 2020 issue of Journal of System Safety
New System Safety Process for New Business Opportunities
Get PDFThis paper outlines an approach to developing and implementing a systems safety process for new business applications in industries without existing system safety processes. It describes the desired characteristics of such a process and extends the discussion to include the basic needs and content of any systems safety process in general.
New business applications are being created every day, and safety must be considered in these endeavors. This paper explores how to determine if such applications warrant a system safety process so that potential risk is identi-fied and appropriate prevention, detection, and mitigation content and capabilities are designed, developed, implemented, tested and verified prior to the application deliverable being placed into customer hands.
The role of management in determining what is unacceptable risk and how risk is allocated between participating business and customer entities is also discussed. In this paper, “system” is used as a generic term for the product the company plans to deliver. 
Vaccine Safety
Get PDFWe are now near the end of the second year of the COVID-19 pandemic, and it has been a year since the first International System Safety Society (ISSS) Conference coronavirus presentation. This past year has seen the development and distribution of several vaccines, as predicted in the previous publication about the pandemic. These new weapons against disease will save millions of lives all over the globe in the next few years — and they were developed faster than any vaccine in medical history. Yet these same vaccines have been the victim of numerous allegations from the start. In fact, their strongest virtue — the speed with which they were developed and distributed — is seen by their critics as a fault, possibly resulting in an unsafe or insufficiently tested product. Is there any truth to these claims? How do these vaccines work? And how are they made? Vaccine Safety.
In order to establish an orderly, technically accurate, objective, and comprehensive record of the events of these times that is accessible to the general public and of some use to posterity, this second publication has been prepared. It is also hoped that this report will mitigate some of the concerns that people have about vaccine safety
President's Message: Find Your Way
No full textWhile, at this writing, I will be serving as your president for several more months, due to the frequency and publication process this will be my last message in JSS as president. By way of confession, I am always late to the publisher with my content, but this article in particular has been hard to write. I want you to know it has been a pleasure to serve you and the industry. I wish I had been able to get more done (sometimes I don’t get as much done as I probably should). So, I suppose this letter is an apology that I wasn’t more effective, a “thank you” for allowing me to continue to serve you, and a recognition for the growth we have made in the last couple of years. We, the ISSS, have changed on a number of fronts within the last two years
Workflow between ISO 26262 and ISO 21448 Standards for Autonomous Vehicles
Get PDFAssuring safety is important in autonomous vehicles. The safety related to autonomous vehicles can be primarily viewed from two perspectives: the functional safety (FuSa) perspective and the safety of the intended functionality (SOTIF) perspective. While FuSa ensures the system has an acceptable risk with respect to malfunctions of electrical and electronic components, SOTIF ensures the system has an acceptable risk with respect to functional insufficiencies and performance limitations.
ISO 26262 and ISO 21448 are the state-of-the-art international standards used to ensure compliance with FuSa and SOTIF for autonomous automotive systems, respectively. The ISO 21448 standard mentions the need for alignment of ISO 26262 activities with the ISO 21448 activities and describes the mapping at a very high level. However, given the iterative nature of SOTIF activities in ISO 21448, the workflow between the two standards is not a direct one-toone mapping. Hence, we need a clear understanding how we can align ISO 26262 and ISO 21448 activities, and on how analysis done in one standard can impact the other.
To achieve this, in this paper we propose a detailed workflow between ISO 26262 and ISO 21448 standards. We discuss guidelines on how to find if a change to design due to SOTIF modification can affect FuSa analysis and vice versa. We also discuss the aspects we need to consider for agile development when we want to ensure the system bein
Failure Interval Probabilistic Analysis for Risk-based Decisions - Concorde Crash Example
Get PDFThe DC-6, DC-8, DC-10, Concorde, Boeing 787 and Boeing 737 MAX fatal crashes and nearmisses were analyzed with event interval probabilistic analysis methods. Fleet grounding decisions are the epitome of risk-based decisions, and the most important decision is the first opportunity to ground. The “first opportunity to ground” decision is retrospectively judged to be wrong if, in the immediate future, another accident or cause-and-effect findings leads to the original decision being reversed. Using only data available at the time of the significant events, the analysis examines these risk-based decisions as if it they were made at the event’s instant in time.
The event interval method identified five out of six “first opportunity to ground” decisions correctly, including the Concorde. According to these analyses, the FAA and its predecessor organizations made one correct decision out of five. Use of this method based on statistics and probability would have avoided 503 actual fatalities, plus 9.45 expected value fatalities from additional risk exposure due to flying statistically proven unreliable aircraft. In addition to the reversed decision standard for judging whether these decisions were wrong, the data show that a grounding of the DC-8 and a second grounding of the DC-6 would have been statistically appropriate — but these groundings did not occur.
A specific objective of this paper is to lead the FAA and aircraft manufacturers to using event interval probabilistic analysis in grounding decisions and air-worthiness certification. The cause-and-effect data necessary to identify issues and make corrections are often sparse or nonexistent at the time of the event. Cause-and-effect data can take days or months to acquire and analyze, but event interval timing data are simple because system performance data are available at the instant the event occurs
System Safety in Healthcare: Lessons Learned From Designing for Safety
No full textDesigning for safety is a process. When the right process is followed, results can be great, such as eliminating most of the warranty costs. The opposite is also true in the absence of the right process. There is a saying: “If we don’t know where we are going, that’s where we will go.
System Safety in Healthcare: Application of AI on System Safety
No full textThe purpose of system safety is to prevent bad things from happening. Lately, systems have been using artificial intelligence (AI), and verification and validation is becoming a major challenge. First, we have to understand the four main types of AI, in addition to much-less-used methods on the web. The main types of AI are:
Reactive Machines
Limited Memory
Theory of Mind
Self-aware 
TBD
Get PDFI have been noticing a definite uptick in the number of industry groups that are talking about the benefits of system safety. Many of them don’t know that they are “inventing” an approach that has been successfully used for almost 100 years on millions of projects with a combined value of tens of trillions of dollars. It seems that many of these groups believe they came up with the “new” idea that designing safety into projects is better, less expensive and results in fewer false starts than traditional safety approaches — not to mention that it is also more effective in reducing accident losses.
System safety is an engineering process that starts as early as practical and continues throughout the project’s life until there is no longer value in continuing. Conceptually, system safety consists of three simple steps:
Identify potential hazards.
Control the risks associated with those identified hazards to acceptable levels.
Repeat