ENGINEMAN  1  &  C repair work to be done whenever the need for such work arises. Review  the  Maintenance  and  Material Management   (3-M)   Manual,   OPNAVINST 4790.4,  it  will  make  your  planning  and  schedul- ing  considerably  easier. Materials and Repair Parts The responsibility for maintaining adequate stocks  of  engineroom  repair  parts  and  repair materials belongs at least as much to you as it does to the supply department. The duties of the supply officer are to procure, receive, stow, issue, and account for the support of the ship. However, the supply officer is not the prime user of repair parts and repair materials; the initiative for maintain- ing adequate stocks of repair materials, parts, and equipment must come from the personnel who are going to use such items. Namely You! Basic information on supply matters is given in Military Requirements for PO 3 & 2, NAVED- TRA  10056  (current  edition),  Military  Re- quirements for PO 1 & C, NAVEDTRA 10057 (current   edition),   and   OPNAVINST   4790.4, volume II. Identification  of  Repair Parts and Materials Identification  of  repair  parts  and  materials  is not usually a great problem when you are deal- ing with familiar equipment on your own ship; but it may present problems when you are doing repair  work  for  other  ships,  as  you  would  if assigned to the machine shop on a repair ship or tender. The materials and repair parts to be used are specified for many repair jobs but not for all. When materials or parts are not identified in the instructions  accompanying  a  job,  you  will  either have to use your own judgment or do research to find out just what material or part should be used. When you must make the decision yourself, select materials on the basis of the service condi- tions they must withstand. Operating pressure and operating temperature are primary considerations in  selecting  materials  and  parts  for  most engineroom repair work. The fact that materials and repair parts are not  specified  in  the  instructions  accompanying  a job does not mean that you are free to use your own judgment in selecting parts and materials to accomplish a job. Instead, it usually means that you must know where to look for information on the type of material or repair parts needed, then locate  and  requisition  them  in  order  to  complete the assigned job. There are several shipboard sources of infor- mation that will be useful to you in identifying the  equipment  and/or  the  repair  parts  needed. They   include   the   Coordinated   Shipboard Allowance  List  (COSAL);  nameplates  on  the equipment;  manufacturer’s  technical  manuals; and  ships’  plans,  blueprints,  and  other  drawings. COORDINATED  SHIPBOARD  ALLOW- ANCE  LIST  (COSAL).—The  COSAL  is both a technical and a supply document prepared for an individual ship. It lists the equipment or components required for the ship’s operation; the repair   parts   and   special   tools   required,   the overhaul  and  repair  equipment,  and  the miscellaneous portable items necessary for the care and upkeep of the ship. For your purpose, the COSAL is the basic source   of   information   on   repair   parts   and materials needed for a job. A COSAL gives you information on such items as the noun name of a  system  (engine,  pump,  ejector,  etc.),  the manufacturer’s   name   and   the   I.D.   number (General  Motors  Corporation  #3255),  the technical  manual  number  for  the  system,  the manufacturer’s   drawing   numbers,   and   the Allowance Parts List (APL) numbers for related systems  (governor’s,  starters,  transmissions,  etc.). In addition, COSAL provides specific informa- tion about National Stock numbers (NSNs), units of issue, costs, and the number of items needed. It  may  also  include  lists  of  part  numbers  and Federal  Stock  Numbers  (FSNs)  for  crossover checks. To request materials and repair parts from the supply department aboard ship, you must fill out and submit a NAVSUP Form 1250, a single item consumption/management  document.  If  the  item is not stocked aboard ship, the supply department will requisition the material from a supply activity, using the identifying information that you have given on the NAVSUP Form 1250. However, if 2-20