Engineers minority

Technical requirements Sound engineering practice, essential requirements tarticle 3t The directive includes a particular technical requirement with respect to equipment which presents only a minor pressure hazard. For such equipment the essential requirements and the certification procedures are not applicable. Instead the so-called sound engineering practice of one of the Member States must be applied. That practice must ensure that design and manufacture takes into account all relevant factors influencing safety during the intended lifetime. The equipment must be accompanied with adequate instruetions for use and must bear the identification of the manufacturer. The CE-marking shall not be applied for such equipment. 

Organic compounds are a major constituent of the FPM at all sites. The major sources of OC are combustion and atmospheric reactions involving gaseous VOCs. As is the case with VOCs, there are hundreds of different OC compounds in the atmosphere. A minor but ubiquitous aerosol constituent is elemental carbon. EC is the nonorganic, black constituent of soot. Combustion and pyrolysis are the only processes that produce EC, and diesel engines and wood burning are the most significant sources. 

The advent of electric motors, steam turbines, and other drivers has relegated the steam engine to a minor position as an industrial driver. It does have the advantages of reliabihty and operating characteristics that are not obtainable with other drivers but so the disadvantage of bulldness and oily exhaust steam. 

At high velocities where turbulence dominates, the main body of flowing fluid is well mixed in the direction normal to the flow, minor differences in temperature and concentration can be neglected, and the film concept can be applied. This describes the flow as if all gradients for temperature and concentration are in a narrow film along the interface with the solid (Nernst 1904), and inside the film conduction and diffusion are the transfer mechanisms. This film concept greatly simplifies the engineering calculation of heat and mass transfer. 

Only a few incidents started with the sudden failure of a major component. Most started with a flaw in a minor component, an instrument that was out of order or not believed, a poor procedure, or a failure to follow procedures or good engineering practice. For want of a nail, the battle was lost. 

Routine operations of many ships have resulted in oil pollution. Cleaning up minor spills on deck and in the engine room is now treated very carefully. Fuel-oil and crude-oil tanks are cleaned from time to time. In the past the polluted oil-water mixture was dumped overboard, but now it must be pumped ashore for treatment. 

Many engineers appreciate that painting, which should be a minor part of an engineering project, can assume major proportions if there are problems or premature failures. For any painting work for which premature failure is economically or practically unacceptable, it is advisable to use full-time, qualified paint inspection. Note that part-time inspection, or visit inspection, can in some ways be worse than no inspection at all. 

Very few pump installations follow Hydraulic Institute recommendations. A minority of installations fail to follow reasonable engineering practices or even common sense. Therefore, it should not be a surprise that centrifugal pump applications often exhibit chronic reliability and maintenance problems. 

Dalton s Faw has been proved experimentally to be somewhat inaccurate, the total pressure often being higher than the sum of the partial pressures. This is especially true during transitions as pressure is increased. However, for engineering purposes it is the best rule available and the error is minor. 

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