• Outcome: Assessment of Safety – determine the relativity of a safety
• Risk: Potential for unwanted i.e. unsafe outcome – Potential harm for the lives, well-being and health especially of the people
• Two Aspects of Risks: 1) Nature of outcomes: ð Physical Injury

  ð Negative impacts on the quality of life in any sense

  ð Surrounding damage

  2) Uncertainty related to the surrounding outcomes

  ð It can not be quantified

  ð Useful Test: How much a sufferer (victim) would suffer, lose or   pay or   offender (wrong-doer) regrets for each possible outcome?

• Some Sources of Uncertainty:
• Manufacture: Design Error, Assembling Error, Component’s quality
• Installation and Operation: Installation Error and Cost Over-runs
• Operator Error, Equipment Failure, Volatility in Input-costs, External Factors e.g. weather
• • End of life of an equipment, machine, component, etc. Dismantling and disposal costs and their impacts usually on the environment
  • Statistical View-point: Events determined by the Probability Distribution: Probability Distribution is usually derived from the statistical analysis of the past and present observations or surveys and future assessment or inference in the similar situations

  –Hence risk is an Objective Issue with respect to Statistical View-point

  • Scenario View-point:

  –Past observation is not a reliable guide to the future:

  • Technological, social and environmental changes affect an activity
  • Results are influenced by the social and corporate cultures

  –Hence risk is a Subjective Issue with respect to Scenario View-point

  Consensus: It is a process to make a decision in which consent, agreement or agreeing-opinion of all the participants (in a group) is sought; Group decision-making process  

  Professional Indemnity Insurance: An Indemnity Insurance made to protect the professional image, reputation  , status, etc of a professional organisation or society 

• • Complete and Perfect Safety is practically Impossible:
  • How a safety measure is safe enough?
  • Are the risks distributed in a situation or process differently / uniformly?
  • Quantification of Indirect Costs is Difficult:
  • What is the Value of a Human Life?
  • What Indirect Costs should be Considered while considering the Important Costs or Total Costs?
  • Minimum total costs may exceed the socially acceptable risk:
  • Who should decide it?
  • Attitudes are influenced by a range of factors:
  • Voluntary versus Involuntary
  • Controllable versus Uncontrollable
  • Work-related versus Recreational
  • Severeness of a Potential Harm
  • • Extent of relevant knowledge & skills about the safety
    • Individual preferences to observe the safety
    • Ethical Attitudes don’t always appear rational:
    • Should this affect our respect to them?
    • Societal attitudes towards Risk and Risk Management
    • Obscured by the diversity individual attitudes
    • Must be assessed indirectly:

    –By the expert groups

    –Public interest advocacy bodies

    –Focus the groups (whether random or targeted selection)

    –Judicial determination:

    -- Societal norms develop from the history of litigation

    • Social attitudes evolve with the lapse of time:
    • Continual need for informed / indicative consent
    • • Safe Exits and Prudent Avoidance:
      • Safe Exits (usually act as the last Line of Defence):

      –Equipment may fail gradually safely or unsafe equipment can be abandoned safely

      • ‘Dead-Man’s Handle or Switch’ for train drivers or machine operators
      • Safety-belts, Airbags, etc in a car / other vehicles

      –Plane passengers can escape (in an emergency landing) safely by using:

      • e.g. aircraft parachutes or escape-slides
      • Prudent Avoidance (a quasi-legal obligation):

      –Avoid the people from becoming the victim of the unjustified risks

      • Both (above-mentioned two factors) require the coordination between the designers, managers, users & the public

      • Conclusions:

        • Engineers have a significant concern with the Safety:
        • Duty (for safe and safety designing / engineering management or engineering operation) for equipment, project, etc and towards the public
        • Issues in considering Risk & Safety:
        • Subjective, with respect to the variations in individual assessment
        • There is often a trade-off between cost and safety
        • Tool for arriving at a Reasonable Balance:
        • Public involvement in decision making
        • Risk Management while designing
        • Safe Exits and Prudent Avoidance