Sound engineering judgment

As with troubleshooting, parameter estimation is not an exact science. The facade of statistical and mathematical routines coupled with sophisticated simulation models masks the underlying uncertainties in the measurements and the models. It must be understood that the resultant parameter values embody all of the uncertainties in the measurements, underlying database, and the model. The impact of these uncertainties can be minimized by exercising sound engineering judgment founded upon a famiharity with unit operation and engineering fundamentals. 

It is intended that the use of the tables should be combined with sound engineering judgment and consideration of all relevant factors. Eurthermore, all the solutions presented may not be applicable to a given situation. It should also be recognized that the solutions presented could introduce potential hazards that were not originally present. Therefore, it is necessary to use the table in the context of the total design concept to insure that all hazards have been considered. 

API standards are published to facilitate the broad availability of proven, sound engineering and operating practices. These standards are not intended to obviate the need for applying sound engineering judgment regarding when and where these standards should be utilized. The formulation and publication of API standards is not intended in any way to inhibit anyone from using any other practices. 

Use of sound engineering judgment is the best procedure to ensure a cost-effective project. A poorly executed minimal initial feasibility study may be costly... 

Assigning prooftest frequencies for complex, safety-instrumentation loops requires sound engineering judgment for simple systems. For more complex, interlock systems, the frequency is a function of the tolerable hazard rates. For example, DuPont Sabine River Works (Orange, Texas) reported it had 35,000 instruments in service. Every safety interlock is... 

AH these marvelous and posverful tools available today put an extra burden on today s engineers. They must still have a thorough understanding of the fundamentals, develop a feel" of the physical phenomena, be able to put the data into proper perspective, and make sound engineering judgments, just like their predecessors, However, they must do it much better, and much... 

Documentation should confine itself to facts and sound engineering judgment. It should not contain any speculation, particularly to do with major accident scenarios. Any estimates as to possible incidents (such as occurs during a PHA) should be based on professional judgment and plant experience. 

System safety analysis and risk assessment do not eliminate reliance on sound engineering judgment. 

Even when only limited data are available, it is often possible to develop suitable models for most common cases by combining the available data with sound engineering judgment and expert experience. 

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