33 C.F.R. § 117.4 Definitions.
Title 33 - Navigation and Navigable Waters
Certain terms used in this part are defined in this section. Appurtenance. The term “appurtenance” means an attachment or accessory extending beyond the hull or superstructure that is not an integral part of the vessel and is not needed for a vessel's piloting, propelling, controlling, or collision avoidance capabilities. Lowerable. The term “lowerable” means the nonstructural vessel appurtenance can be mechanically or manually lowered and raised again. The term “lowerable” also applies to a nonstructural vessel appurtenance which can be modified to make the item flexible, hinged, collapsible, or telescopic such that it can be mechanically or manually lowered and raised again. Failure to make the modification is considered equivalent to refusing to lower a lowerable nonstructural appurtenance that is not essential to navigation. Examples of appurtenances which are considered to be lowerable include, but are not limited to, fishing outriggers, radio antennae, television antennae, false stacks, and masts purely for ornamental purposes. Examples of appurtenances which are not considered to be lowerable include, but are not limited to, radar antennae, flying bridges, sailboat masts, piledriver leads, spud frames on hydraulic dredges, drilling derricks' substructures and buildings, cranes on drilling or construction vessels, or other items of permanent and fixed equipment. Nonstructural. The term “nonstructural” means that the item is not rigidly fixed to the vessel and is thus susceptible to relocation or alteration. Not essential to navigation. The term “not essential to navigation” means the nonstructural vessel appurtenance does not adversely affect the vessel's piloting, propulsion, control, or collision avoidance capabilities when in the lowered position. [CGD 91–059, 59 FR 16563, Apr. 7, 1994]
Title 33: Navigation and Navigable Waters
PART 117—DRAWBRIDGE OPERATION REGULATIONS
Subpart A—General Requirements
§ 117.4 Definitions.
