Engines safely devices

The safe operation of such processes depends on the design and provision of engineered safety devices, and on good operating practices, to prevent a dangerous situation developing, and to minimise the consequences of any incident that arises from the failure of these safeguards. 

Engineered safely equipment is preferred over the reliance on personal protective equipment, and the fume hood is one such engineered safety device that is nearly ubiquitous in laboratories. Laboratories concerned with biological specimens (microbes, spores) also commonly are equipped with biological safety cabinets. The following section provides basic information on the function and application of these devices. The purpose here is not to provide design or installation instructions, since most users will find this equipment already installed in their work spaces. Rather, this information is to allow optimal use to be made of the installation that is preexisting. 

The latter concept implies providing local life support systems for unfriendly environments. By now, Ukrainian scientists and engineers have developed a variety of processes for potable water treatment by adsorption, electrochemical oxidation, electrocoagulation, electro-coprecipitation, electrodialysis, electrofloatation, floatation, membrane techniques etc. Each family must get small units for water purification, air cleaning and removal of hazardous substances from the food as soon as possible, for it may take decades to introduce cleaner production on a national scale. Here, we should follow the example of Western business people who bring with them to Ukraine devices enabling a safe existence in this unfriendly environment. 

FIG. 23-50 Feed distributor devices for horizontal blowdown drums/catch tanks. (Guidelines for Pressure Relief and Effluent Handling Systems, Center for Chemical Process Safely (CCPS) of the American Institute of Chemical Engineers (AlChE) copyright 1988 AlChE and reproduced with permission.). 

Engine Overspeed Stops. Every compressor prime mover, except electrical induction or synchronous motors, shall be provided with an automatic device that is designed to shut down the unit before the maximum safe speed of either the prime mover or driven unit is exceeded. 

As a result of current - and voltage - limitations required, and in case of classic Ex i-engineering (see Section 6.9.5), some restrictions are imposed upon the intrinsically safe variant. The number of field devices to be connected to the bus system is limited to approximately five, in particular in case of a current consumption exceeding the designated value of 10 mA. Besides, the length of cables shall be limited to some 100 m due to capacitance and inductance limitations. Away out is demonstrated below (FISCO model, see Section 6.9.6). 

The nozzle is a relatively short device, a few pipe diameters long at most, and the flow will establish itself so rapidly that the control engineer may safely content himself with a steady-state analysis. We may begin with the analysis of Section 4.2, which led to the differential form of the energy equation (4. IS) for fluid flow where no useful work is done. This is repeated below ... 

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