MATERIAL CONDITIONS OF READINESS There are three material conditions of readiness. Those  conditions  are  named  XRAY,  YOKE,  and ZEBRA. When set, each condition affords the ship with a level of protection, with XRAY being the least and ZEBRA the most. Some fittings or closures on a ship may not be classified although the majority of them are classified. They are identified by a classification plate affixed  to  the  closure  or  fitting,  or  sometimes  the classification is painted on the bulkhead next to the item. Ship’s  instructions  (and  Navy  instructions)  specify what type of classification an item should hold, how it will be marked, and when that condition should be set. The commanding officer of the ship is authorized by instruction to alter this to a small extent if he/she desires but basically this system is standard Navywide. XRAY. Provides the least watertight integrity and the greatest ease of access throughout the ship. It is set when the threat to the ship is minimal. Condition XRAY is set during working hours when the ship is in port, when there is no danger of attack, and when there is no threat from bad weather. All fittings marked with a black X and circle X are closed when condition XRAY is set. YOKE. Provides a greater degree of watertight integrity than condition XRAY but to a lesser degree than the maximum condition. YOKE is normally set at sea and in port during wartime. All fittings marked with Xs and Ys, Circle X, and Circle Y are closed when condition YOKE is set. ZEBRA .  Provides  the  greatest  degree  of subdivision and watertight integrity to the ship. It is the maximum state of readiness for the ship’s survivability system. Condition ZEBRA is set when the following situations occur: 1.  Immediately when GQ is sounded 2.  When entering or leaving port in wartime 3.  To localize damage and control fire and flooding when the crew is not at GQ 4.  At  any  time  the  CO  deems  the  maximum condition of survivability should be set All fittings marked with X or Y, Circle X, Circle Y, Z, Circle Z, and DOG Zs are closed when condition ZEBRA is set. The  setting  of  material  conditions  is  normally carried out by the division or department responsible for the  compartment  and  is  accomplished  by  using  the compartment checkoff lists (CCOLs). In an emergency the repair party personnel responding to the casualty assisted by those Sailors in the area will set the required condition to restrict the spread of damage. CCOLs are a tool used by repair party personnel to find the damage control fittings and closures in each compartment. The fittings and closures are identified by name (type) and a number that represent the location of the fitting by deck, the frame it is located at, and the side of the space similar to the compartment identification process. The CCOL list is posted in each space near the entrance and should be kept up to date by the division who owns the space. An example of a CCOL is shown in (fig. 12-2). The normal setting of a material condition should be logged in the Damage Control Closure Log by each division or repair party completing the setting. Any exceptions to the setting should also be noted in the log so DCC/OOD are aware of the reduction in the ship’s ability to restrict the spread of potential damage. This log and the Inoperative Fitting Log are maintained in either DCC or on the quarterdeck by the OOD. If you have a need to break (open) a fitting that should be normally  set  in  a  specific  condition,  you  must  first request it open and then log it in before opening the fitting. If you don’t do this, you are in violation of the setting and have jeopardized your shipmate’s survival. When you have completed work in a space that you needed a fitting/closure open, close it first, then log it closed. Now those who maintain the log will have a clear picture of what is open and closed in a given area of the ship. In addition to the closure log, a log for inoperative fittings and closures exists. As its name implies, this log lists all DC-related fittings and closures on the ship that don’t work properly. It becomes a tracking tool for future maintenance. A modified condition YOKE or modified condition ZEBRA is sometimes set, rather than the normal setting of XRAY, YOKE, or ZEBRA. These are settings of convenience at the discretion of the CO. 12-11 Student Notes: