Conceptual difficulties in Risk-Benefit Analysis
Both risks and benefits lie in future heavy discounting of future because…
Failure modes and effect analysis (FMEA)
This approach systematically examines the failure modes of each component, without however, focusing on relationships among the elements of a complex system. Fault Tree Analysis (FTA) A system failure is proposed and then events are traced back to possible causes at the component level. The reverse of the fault-tree analysis is ‘event – tree analysis’. This method most effectively illustrates the disciplined approach required to capture as much as possible of everything that affects proper functioning and safety of a complex system.
Testing strategies for safety
Some commonly used testing methods: Using the past experience in checking the…
Uncertainties encountered in design process
A decision on maximizing profit or maximizing the return on investment. Uncertainties…
Knowledge of risk for better safety
Robert Stephenson writes that all the accidents, the harms caused and the means used to repair the damage should be recorded for the benefit of the younger Members of Profession. A faithful account of those accidents and the damage containment was really more valuable than the description of successful work. Hence it is imperative that knowledge of risks will definitely help to attain better safety. But it should be borne in mind, that still gaps remain, because i) there are some industries where information…
Safety in a commodity comes with a price – Explain.
Absolute safety is never possible to attain and safety can be improved in an engineering product only with an increase in cost. On the other hand, unsafe products incur secondary costs to the producer beyond the primary (production) costs, like warranty costs loss of goodwill, loss of customers, litigation costs, downtime costs in manufacturing, etc. Figure indicates that P- Primary costs are high for a highly safe (low risk) product and S- Secondary costs are high for a highly risky (low safe) product. If we draw a curve T=P+S as shown, there is a point at which costs are minimum below which the cost cannot be reduced. If the risk at Minimum Total Cost Point is not acceptable, then the producer has to choose a lower acceptable risk value in which case the total cost will be higher than M and the product designed accordingly. It should now be…
Problems faced by engineers about public concept of safety
The optimistic attitude that things that are familiar, that have not caused harm before and over which we have some control present no risks. The serious shock people feel when an accident kills or maims people in large numbers or harms those we know, even though statistically speaking such accidents might occur infrequently.
Secondary Costs of Products
Cost of products is High, if designed unsafely Returns and Warranty Expenses Loss of Customer Goodwill Cost of litigation Loss of Customers due to injuries in using it Cost of rework, lost time in attending to design problems Manufacturer’s understanding of the risk in a product is necessary: To help reduce secondary costs To know the possible risk for purposes of pricing, disclaimers, legal terms and conditions, etc. To know the cost of reducing the risks To take a decision before finalizing the design. Buyer’s understanding of the risk in a product is necessary:…
