Terms Used In 48 CFR Part 3015 - Contracting by Negotiation

• sound signal: as used in this part shall mean the audible sound signal, authorized as a private aid to navigation, to mark a structure for the safety of marine commerce whenever the visibility has been reduced by fog, mist, rain, falling snow, smoke, dust, or other phenomena. See 33 CFR 67.01-5
• structures: as used in this part shall include all fixed structures, temporary or permanent, for which a Corps of Engineers' permit is issued. See 33 CFR 67.01-5