Conditions for Designing for Safety
Clarify Conditions
- Operating Conditions
- Requirements
- Expectations: implicit requirements and wishes
Conditions for Designing for Safety
Clarify Conditions
- Operating Conditions
- Requirements
- Expectations: implicit requirements and wishes
Direct Safety
- Safe-life principle
- Fail-safe principle
- Redundancy principle
Errors in a system
- System error
- operating error
Fail-safe principle
Failure of a system function or a component fracture may occur without grave consequences
Indirect Safety Principles
- Protective systems
- Protective devices
- Protective barriers
Indirect Safety
- Installations that have a securing function and separate the danger from the surroundings/ environment
- Applied, when no direct safety measures can be applied
Material Aspect of Safety Technology
- The safety of a product can be increased by choosing a material that suits the operating conditions of the product
- Determining the operating conditions is crucial for the choice of materials:
- Corrosion resistant materials
- Fatigue resistant material
- Materials that have a good adhesion to lubricants
Protection
… is the reception of risk by suitable means to reduce the frequency of the occurrence or the extent of damage or both
Protective Barriers
They fulfill protective functions without acting protectively, i.e. no signal transformation. They protect by separating
Protective Systems
They react protectively when danger occurs I.e. they have final transformation and capture the danger and can eliminate it actively
Redundancy principle
Increase in safety via redundant safety arrangements of a system/ system element
Redundancy Types
- Active redundancy
- Passive redundancy
- Principle redundancy
Risk Limit
… is the largest still acceptable system-specific risk relating to a particular technical process or situation
Risk Limit
… is the largest still acceptable system-specific risk relating to a particular technical process or situation
Types of Safe Embodiment Design
- Direct safety
- Indirect safety
- Warnings
Safe-Life Measures
- Over-dimensioning of parts
- Clear and simple embodiment design
- Field-tests for determining the actual loads
- Employ experienced interdisciplinary teams for the development
- Documented quality assurance over the complete life-cycle
- Inspection/maintanance
Safe-life principle
All possible incidents are overcome without breakdown or a malfunction
Safety
… is a state in which the risk is smaller than the risk limit
Safety Measures
- Design measures
- Safe control
- Safe regulation
- Safe monitoring
