Resources - System Safety

Risk Management Decision Making

For any system safety effort to succeed there must be a commitment on the part of management. There must be mutual confidence between program managers and system safety management. Program managers need to have confidence that safety decisions are made with professional competence. System safety management and engineering must know that their actions will receive full program management attention and support. Safety personnel need to have a clear understanding of the system safety task along with the authority and resources to accomplish the task. Decision-makers need to be fully aware of the risk they are taking when they make their decisions. They have to manage program safety risk. For effective safety risk management, program managers should:

  • Ensure that competent, responsible, and qualified engineers be assigned in program offices and contractor organizations to manage the system safety program.
  • Ensure that system safety managers are placed within the organizational structure so that they have the authority and organizational flexibility to perform effectively.
  • Ensure that all known hazards and their associated risks are defined, documented, and tracked as a program policy so that the decision-makers are made aware of the risks being assumed when the system becomes operational.
  • Require that an assessment of safety risk be presented as a part of program reviews and at decision milestones. Make decisions on risk acceptability for the program and accept responsibility for that decision.

Safety Order of Precedence

One of the fundamental principles of system safety is the Safety Order of Precedence in eliminating, controlling or mitigating a hazard. The Safety Order of Precedence is shown in Table 3-7. It will be referred to several times throughout the remaining chapters of this handbook.

Description Priority Definition
Design for minimum risk. 1 Design to eliminate risks. If the identified risk cannot be eliminated, reduce it to an acceptable level through design selection.
Incorporate safety devices. 2 If identified risks cannot be eliminated through design selection, reduce the risk via the use of fixed, automatic, or other safety design features or devices. Provisions shall be made for periodic functional checks of safety devices.
Provide warning devices. 3 When neither design nor safety devices can effectively eliminate identified risks or adequately reduce risk, devices shall be used to detect the condition and to produce an adequate warning signal. Warning signals and their application shall be designed to minimize the likelihood of inappropriate human reaction and response. Warning signs and placards shall be provided to alert operational and support personnel of such risks as exposure to high voltage and heavy objects.
Develop procedures and training. 4 Where it is impractical to eliminate risks through design selection or specific safety and warning devices, procedures and training are used. However, concurrence of authority is usually required when procedures and training are applied to reduce risks of catastrophic, hazardous, major, or critical severity.


  1. Design for Minimum Risk: Design hardware systems that use low voltage rather than high voltage where access is provided for maintenance activities.
  2. Incorporate Safety Devices If low voltage is unsuitable, provide interlocks.
  3. Provide warning devices If safety devices are not practical, provide warning placards
  4. Develop procedures and training Train maintainers to shut off power before opening high voltage panels

Behavioral-Based Safety

Safety management must be based on the behavior of people and the organizational culture. Everyone has a responsibility for safety and should participate in safety management efforts. Modern organization safety strategy has progressed from “safety by compliance” to more of an appropriate concept of “prevention by planning”. Reliance on compliance could translate to after-the-fact hazard detection, which does not identify organizational errors, that are often times, the contributors to accidents.

Modern safety management, i.e.--“system safety management”-- adopts techniques of system theory, statistical analysis, behavioral sciences and the continuous improvement concept. Two elements critical to this modern approach are a good organizational safety culture and people involvement. The establishment of system safety working groups, analysis teams, and product teams accomplishes a positive cultural involvement when there are consensus efforts to conduct hazard analysis and manage system safety programs.

Real-time safety analysis is conducted when operational personnel are involved in the identification of hazards and risks, which is the key to behavioral-based safety. The concept consists of a “train-the-trainer” format. A selected safety team is provided the necessary tools and is taught how to:

  • Identify hazards, unsafe acts or conditions;
  • Identify “at risk” behaviors;
  • Collect the information in a readily available format for providing immediate feedback;
  • Train front-line people to implement and take responsibility for day-to-day operation of the program.

The behavioral-based safety process allows an organization to create and maintain a positive safety culture that continually reinforces safe behaviors over unsafe behaviors. This will ultimately result in a reduction of risk.

Source: FAA Office of System Safety

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Copyright ©2000-2019 Geigle Safety Group, Inc. All rights reserved. Federal copyright prohibits unauthorized reproduction by any means without permission. Disclaimer: This material is for training purposes only to inform the reader of occupational safety and health best practices and general compliance requirement and is not a substitute for provisions of the OSH Act of 1970 or any governmental regulatory agency. CertiSafety is a division of Geigle Safety Group, Inc., and is not connected or affiliated with the U.S. Department of Labor (DOL), or the Occupational Safety and Health Administration (OSHA).