NFPA 1192-2018 Standard on Recreational Vehicles.
3.3.19 Drain. A pipe that carries waste, water, or liquid-borne wastes in a drainage system. Fixture Drain. The drain from a fxtures trap to the drain outlet or to the junction of that drain with any other drain pipe. Main Drain(s). The lowest piping of a drainage system that receives the liquid or body waste discharge from all the fxtures within the system and conducts these wastes to the drain outlet(s). 3.3.20 Drain Hose. A hose used for connecting the liquid or body waste drain outlet to a sewer inlet connection. 3.3.21 Drain Outlet. The lowest end of a main or secondary drain to which a sewer connection is made. 3.3.22 Fixed Maximum Liquid Level Gauge. A fxed liquid level gauge that indicates the liquid level at which the container is flled to its maximum permitted flling limit. [58, 2017] 3.3.23 Fixtures (Plumbing). Receptacles, devices, or applian‐ ces that are supplied with water or that receive liquid or liquid- borne wastes for discharge into the drainage system. 3.3.24 Flexible Drainage Connector. A bendable tube, hose, or hose assembly used for conveying liquid waste between two drain, waste, vent (DWV) ftting components in a recreational vehicle drainage system. 3.3.25 Flood Level. The level in the receptacle over which water would overfow to the outside of the receptacle. 3.3.26 Frame. Chassis rail and any addition thereto of equal or greater strength.
3.3.27 Fuel Cell Device. An electrochemical system that consumes fuel to produce an electric current. 3.3.28 Fuel Cell System. The complete aggregate of equip‐ ment used to convert chemical fuel into usable electricity and typically consists of a reformer, a stack, a power inverter, and auxiliary equipment. 3.3.29 Fuel System. Any arrangement of pipe, tubing, fttings, connectors, tanks, controls, valves, and devices designed and intended to supply or control the fow of fuel. 3.3.30 Grade. See 3.3.53, Slope. 3.3.31* Gross Trailer Area. The total plan area measured to the maximum horizontal projections of exterior walls in the set-up mode. 3.3.32 Hose. A fexible tube for conveying a liquid or gas. 3.3.33 Hose Nozzle Valve. The terminal output end of a dispensing system hose. 3.3.34 Identifed (as applied to equipment). Recognizable as suitable for the specifc purpose, function, use, environment, application, and so forth, where described in a particular code requirement. [70:100] 3.3.35* Interior Finish. For recreational vehicles, the exposed interior surface in combination with the substrate to which it is applied.NFPA 1192 pdf download.