DRAFT FOR MODIFICATION OF PLANTS Engineering of change occupies an important place in any company- without change, one becomes stagnant, with change, one needs to be very careful in avoiding accidents. Many accidents (e.g. Flixborough) took place due to modifications. A guideline is given below on change. Sometimes engineering work on the plant goes beyond mere maintenance and could constitute modification. Such modifications involves changes in the plant and/or process and can introduce a hazard. It is essential to adopt a system for identifying and controlling modification.   Procedure for modification Before authorizing a modification particular attention should be paid to ensuring that : 1. The number and size of relief valves required are not changed (or any necessary changes are specified) 2. The electricity area classification is not changed 3. There are no effects that may alter the standard of safety 4. The appropriate engineering standards are followed 5. The right material of construction and fabrication standards are used 6. Existing equipment is not subjected to conditions beyond the design basis without checking that it can withstand new conditions 7. Any necessary changes in operations, conditions are made 8. Adequate instruction and training are provided to operating and maintenance teams. A proper, nominated and qualified team should evaluate the modification (if large enough, go for a MINI HAZOP) from the criteria mentioned.