Safety Compliance Assessment
- Safety compliance assessment
- the safety engineering
task during which
a work product, process, or service is analyzed and assessed to determine its
conformance with the safety program, any contractual safety standards,
applicable safety-related laws and regulations,
and to applicable safety-related requirements
As illustrated in the preceding figure, Safety Compliance Assessment is part of the following inheritance hierarchy:
- Type: Concrete
- Superclass: Safety Task
- Subclasses:
The typical responsibilities of Safety Compliance Assessment are to:
- Develop and Document Evidence of Safety
Analyze, assess, and thereby develop evidence that the:
- Safety requirements
of the application are appropriate.
- Associated architecture, design, implementation, integration, testing, and deployment ensure that the resulting:
- Safety risks are acceptable.
- Required level of safety is met.
- Development process supports the achievement of the:
- Acceptable safety risks.
- Required level of safety.
- Development organization supports the achievement of the:
- Acceptable safety risks.
- Required level of safety.
- Justify Certification
Justify the
safety certificate
of the application via the evidence recorded in the resulting
safety compliance report.
Safety Compliance Assessment typically may begin when the following preconditions hold:
- The safety team
is adequately staffed and trained in safety compliance assessment.
Safety Compliance Assessment is typically complete when the following postconditions hold:
Safety Compliance Assessment typically involves the
safety team performing the following steps in an iterative,
incremental, parallel, and time-boxed manner:
- Assessment of Safety Program for Safety Compliance:
- Analyze, assess, and thereby develop safety arguments that justify that the implemented safety program conforms
to the safety program documented in the
safety program plan.
- Analyze, assess, and thereby develop safety arguments that justify that the implemented safety program conforms
to all contractual safety standards.
- Assessment of Application SafetyCompliance:
- Analyze, assess, and thereby develop safety arguments that justify that the safety requirements are appropriate
based on the safety risk analysis report.
- Analyze, assess, and thereby develop safety arguments that justify that the architectural
safeguards (i.e., safety architectural mechanisms) are appropriate:
- Identify or determine the safety-related or safety-critical components of the application.
- Determine the safety integrity levels of these components.
- Determine the way these safety-related or safety-critical components fulfill their safety
requirements and achieve their safety integrity levels.
- Determine the means by which the fulfillment of these requirements and the achievement of these safety
integrity levels will be verified (e.g., analytical arguments, safety testing).
- Analyze the inclusion of commercial off-the-shelf (COTS) or reused components with regard to safety.
- Analyze, assess, and develop safety arguments that thereby justify that the:
- Design supports the achievement of the acceptable safety risks and the required level of safety.
- Implementation supports the achievement of the acceptable safety risks and the required level of safety.
- Integration supports the achievement of the acceptable safety risks and the required level of safety.
- Installation and configuration supports the achievement of the acceptable safety risks and the required level of safety.
- Assessment of Process Support for Safety Compliance:
- Analyze the ability of the development process to achieve the necessary levels of safety:
- Identify the accidents and hazards that the process will specifically address.
- Identify any relevant standards and analyze conformance of the process to these standards.
- Analyze the historical data supporting the success of the development process with regards to safety.
- Analyze the development environment and tools for their support of safety.
- Analyze the ability of the Safety Program Plan to achieve the necessary levels of safety.
- Compliance:
- Analyze the organizational structure
- Analyze staffing including training and experience
- Develop Safety Compliance Report
- Update Safety Compliance Repository
Safety Compliance Assessment is typically performed
using the following techniques:
- Logging
- Operational Testing
- Reliability Growth Modeling
- Documentation content and format standards
- Document templates
- Document inspection checklists
Safety Compliance Assessment typically results in the production of the following work products:
- The scope of safety compliance assessment is an entire application, which can be a system containing data,
hardware, software, personnel, and procedural components.
- Safety compliance assessment should be performed during the entire life cycle from conception through retirement
(i.e., as long as safety hazards are relevant).
- Safety compliance assessment should be an ongoing task that produces and delivers different versions of the safety
compliance report during the course of development:
- A preliminary version that analyzes safety engineering and justifies confidence in achieving the
safety goals in terms of the safety process, staffing, training, and planning.
- An interim version that justifies confidence in achieving the safety goals in terms of the elicited,
analyzed, and specified safety requirements including (where appropriate) the use formal methods to produce
formally-specified safety requirements.
- A deliverable version that justifies confidence in achieving the safety goals and requirements in terms of the
safety architectural mechanisms, designs, implementations, integration, testing, and deployment.
- An operational version that justifies confidence in maintaining the achievement of the safety goals in terms of
the maintenance and enhancement changes to the safety architectural mechanisms, designs, implementations,
integration, testing, and deployment.
- Not every defect (fault) can cause a failure that leads to an accident (causes harm to an asset). Thus, safety
compliance assessment is only interested in those defects that are hazardous.
- While there is a significant overlap between safety and reliability, as system can be safe without being reliable
(common failures do not cause accidents) and a system can be reliable without being safe (rare failures cause
serious accidents). Thus, although safety Compliance Assessment can use some of the same techniques as
reliability analysis, the use of these techniques should be limited to hazardous situations.
