Safety precept

An OSP is a safety precept that that is directed at the operational phase. These precepts are operational safety rules that must be adhered to during system operation. One aspect of OSPs is that they may directly spawn the need for DSPs that will help realize the OSP via design methods. Although the development PM has no influence during system operation, the OSPs will provide guidance for many design features that will need to be implemented in order to meet the OSPs. An example OSP might be The unmanned system shall be considered unsafe until a safe state can be verified. ... 

A PSP is a safety precept that is directed specifically at organizational goals, tasks, policy, standards, and/or processes that will help implement safety into the system development process. These precepts offer safety guidance, for the PM, which will effect mishap risk reduction through an effective and well-planned safety program. When the PSPs are closely followed, the culture and tasks are set in place for an efficient and successful SSP. An example PSP might be The program shall ensure that COTS software is assessed for safety as a component in the system environment and not as an external isolated element. See Safety Precepts, for additional related information. 

A safety precept is worded as a nonspecific and unrestricted safety objective that provides a focus for addressing potential safety issues that present notable mishap risk. Precepts are intentionally general and not prescriptive in nature they provide a goal, which may be achieved via numerous possible options. Precepts provide a focus and objective as opposed to a detailed solution. The need for a safety precept may result from the desire to mitigate certain hazards, hazard types, TLMs, or special safety concerns. 

The Three Laws of Robotics developed by Isaac Asimov in his books on robots (circa 1939) provide a good example of safety precepts. These precepts merely state what the end goal must be, but not how to specifically accomplish the end goal. The detailed implementation could be different for different robotic systems, or it could change as technology improves. The Three Laws of Robotics are ... 

Safety precepts should meet the following criteria, as a minimum, in order to be valuable and effective for system designers ... 

Safety precepts must provide value in the guidance they provide. K they do not help the safety or the design organizations, then they are of no worth to the program. 

Safety precepts must provide general safety guidance or safety objectives. The goal is to provide a general focus and direction on a particular safety issue, not a detailed design requirement. 

Safety precepts must provide a framework for safety reasoning. Precepts should stimulate thinking on both primary and secondary aspect of the safety issue. 

Safety precepts should allow for tailoring or options in the specific implementation, since different applications may have some unique variances. 

A safety precept should give system developers and users confidence that the particular safety concern will be relatively safe if the precept is followed. 

In order to completely facilitate safety guidance and direction, safety precepts have been subdivided into three categories, whereby each category is aimed at a specific area of program influence. These categories include the following ... 

An OSP is a safety precept that that is directed at the operational phase. These precepts are operational safety rules that must be adhered to... 

The objective of system safety is to develop a system that provides acceptable minimum mishap risk. The basic system safety philosophy for achieving this goal is to confront hazards, mishaps, and risk at three different levels of safety defense. These levels of defense are engineered into the system design. This layer of protection philosophy is summarized by the following three safety precepts ... 

TLMs should be established early in the SSP, generally during the PHL analysis or the PHA phases. Each unique system will have its own unique set of TLMs. As TLMs are established, DSPs and principles can be derived for TLMs and the hazards within a TLM. The safety precepts serve as a mechanism for facilitating the derivation of specific detailed safety requirements for hazard mitigation. 

This text covers biological, chemical, and radiation hazards, and also discusses industrial safety topics such as fire, electrical, and physical safety. It also includes normal laboratory safety precepts which apply to research with laboratory animals. A reference section on animal room safety is also included in the Additional Readings section following the Appendices. 

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