with other civil stations unless it is known that the station concerned is familiar with this series. QOA-QQZ: Reserved for the maritime service. QRA-QUZ: Allocated to the International Telecommunications Union (ITU). All civil stations should have a copy of this series. Therefore, this series may be used with all civil stations unless the station concerned indicates it is unfamiliar with the series. QVA-QZZ: Not allocated. ZAA-ZXZ: Allocated to the Allied military; held by all military stations. ZYA-ZZZ: Reserved for temporary or permanent assignment of meanings on an intra-military basis by any nation, service, or command authorized use of ACP 131. Use of Operating Signals Operating signals either answer a question, give an order, or give advice. Example: Order: ZJL—hoist the following signals. Info: ZJI NKZO—Call sign of ship in company is NKZO. In Allied military stations, a question or request can be implied by preceding the signal with the prosign INT. Example:    INT QRU—Have you anything for me? INT ZJI—What are the call signs of ships in company with you? In reply to a question, an affirmative or a negative sense can usually be implied by using just the basic operating signal. Example: The reply to INT ZOE would be ZOE. If desired though, the operating signal ZUE (affirmative) or ZUG (negative) may be used alone or in conjunction with the signal. Example:    The reply to INT ZOE may be ZUG or ZUG ZOE. In non-Allied military or civil stations, a question can be implied by use of the prosign IMI following the signal. Example: QAR 10 IMI—May I stop listening on the watch frequency for 10 minutes? In reply to a question in the affirmative or negative sense, the letter C (affirmative) or N (negative) is used. Example: The reply to QAR 10 IMI would be QAR 10C. Call signs normally will follow the Q or Z signals; however, they also may precede the operating signal for separation or clarity. Q and Z signals with numbered alternate meanings will be followed, without spacing, by the appropriate number to indicate the meaning intended. Example: ZJH1 means: Your light is unreadable, not trained correctly. Time groups used with Q or Z signals always will be followed, without spacing, by a zone suffix. Any nation, service, or command may prohibit or restrict the military use, within its area of jurisdiction, of any operating signal. However, when such operating signals are received from other users, they must be recognized and acted upon. A knowledge of operating signals is a must for all Signalmen. Section J of ACP 131 contains visual operating signals. Study this section to become more efficient in your job. VISUAL RELAY RESPONSIBILITY In visual communication, relaying is accom- plished automatically when the call-up is made using collective call signs. A message should be relayed concurrent with its reception, when possible, to cut down the time delay between the end of the originator's transmission and its delivery to the final addressee. Chain of Visual Responsibility The general rule for determining the responsibility for any situation is that each addressee is responsible for delivery of the message to addressees beyond themselves in the general direction away from the originator. No rule set forth here, or prescribed by responsible commanders, is to be interpreted as restricting the initiative of any ship in relaying a message to an addressee who does not respond when called. It is the duty of any ship to expedite the transmission of a message by relaying when it is evident that she is in a better position to effect the necessary relay than the ship specifically responsible. When a maneuver alters the position of units and ships relative to the officer in tactical command (OTC), the responsibility for relaying the signals does not alter until completion of the maneuver by all ships. 4-2