Getting the plant ready for commissioning

Usually the conti ol room building (not neces.sarily complete with instrumentation) is one of the eaifiest areas to be handed over and it is from this centie that the plant preparation and commissioning work aie organized, One of the first tasks before any work stans is to check that all the safety equipment is installed, and the emergency and safety procedures are understood by all concerned. 

The next main task consists of cleaning and proving by putting a flow of water or air incrementally through every pipe, valve, fitting and so on at a rate as near as possible to that which will be sustained in actual operation. Where 

After washing or blowing the systems, and carrying out any necessary drying, the plant is usually leak tested by pressurizing with compressed air. This is a most important stage from the hazard point of view since the objective is to ensure there arc no holes in the system which could lead to leakage of flammable, toxic, corrosive or otherwise noxious material. 

At this stage a slip-plate ( spades or blinds ) register is compiled which states where slip-plates are located in the pioccss. The r isia must, of course, be kept up-to-date, and signed by the checker. 

Very often air has to be purged from a system with an inert ga.s — for example, nitrogen. There should be very strict rules for the admission of inert gas into a plant. Basically, none should be allowed in without the express authority of the commissioning manager, who has to be satisfied that all the process equipment has been handed over and therefore entry rules apply to all vessels. 

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