This appendix sets forth guidelines for equipment identification and tagging which are essential for setting up the filing system used by planning. Planning uses the equipment tag numbers in its filing system. Nearly every piece of equipment should be tagged with a number if maintenance work is ever performed on it. The repetitious nature of maintenance work demands that records be kept identifying the circumstances of past work. The past work cannot be improved upon if records are not kept. Records cannot be kept if there is no numbering system to allow arrangement of the files or computer records. It is also not enough to have an equipment number for each item. That number must be clearly visible on the piece of equipment. With this arrangement, it is possible to utilize equipment numbers practically to assist finding equipment and keeping records. A plant might set guidelines if not all equipment is to have an equipment number or tag. All lines and devices critical to processes should have numbers and tags. It may be permissible to exclude certain drain lines smaller than 2 inches. Appendix J equipment type codes recommended giving control valves and their actuators a single number. Similarly, a plant should seriously consider giving a single number to an entire drivetrain such as a pump, its fluid drive, and its motor. Components internal to other equipment such as boiler tube section inside a furnace may be impractical to tag, but numbers can be established for files to track...