Section 217.31 - Priority ratings(a) Levels of priority.(1) There are two levels of priority established by the Energy Priorities and Allocations System regulations, identified by the rating symbols "DO" and "DX".(2) All DO-rated orders have equal priority with each other and take precedence over unrated orders. All DX-rated orders have equal priority with each other and take precedence over DO-rated orders and unrated orders. (For resolution of conflicts among rated orders of equal priority, see § 217.34(c) .)(3) In addition, a Directive regarding priority treatment for a given item issued by the Department of Energy for that item takes precedence over any DX-rated order, DO-rated order, or unrated order, as stipulated in the Directive. (For a full discussion of Directives, see § 217.62 .)(b) Program identification symbols. Program identification symbols indicate which approved program is being supported by a rated order. The list of currently approved programs and their identification symbols are listed in Schedule 1, set forth as an appendix to 15 CFR part 700 . For example, DO-F3 identifies a domestic energy construction program. Additional programs may be approved under the procedures of E.O. 12919 at any time. Program identification symbols do not connote any priority.(c) Priority ratings. A priority rating consists of the rating symbol-DO or DX-and the program identification symbol, such as F1, F2, or F3. Thus, a contract for a domestic energy construction program will contain a DO-F3 or DX-F3 priority rating.