4.3 Electrically powered systems
4.3.1 Electrically powered systems shall be connected to the emergency switchboard as required by Regulation II-1/42 of the 1974 SOLAS Convention, as amended, so as to be powered by the main source of electrical power under normal circumstances and also by the emergency source(s) of electrical power (as identified by Regulations II-1/42.3) when the latter is in operation. Alternatively, for passenger ships carrying more than 36 passengers and built before October 1, 1994, EP systems may be connected to the main lighting system, provided independent batteries provide a backup of at a least 60 minutes and are charged from the main lighting system. Performance of the system while powered by batteries shall meet all the requirements stated herein.
4.3.2 EP systems shall provide the following luminous performances：
4.3.2.1 For planar or line sources such as electroluminescent or electrofluorescent panels, or side emitting fiber optics, the surface of the indicators shall have a minimum luminance of 10 cd/m2.
4.3.2.2 Point sources shall provide a minimum performance as specified in clauses 4.3.2.2.1 and 4.3.2.2.2.
4.3.2.2.1 Miniature incandescent lamps shall provide not less than 150 mcd mean spherical intensity with a spacing of not more than 100 mm between lamps;
4.3.2.2.2 Sub-miniature incandescent lamps and light emitting diodes (LEDs) shall have a minimum intensity of 35 mcd at the center of the appropriate viewing cones. The intensity distribution shall be appropriate to the likely track directions of approach and viewing. For sources which are required to be viewed from a horizontal position, (i.e., deck mounted or horizontal bulkhead mounted fittings) the intensity distribution shall be within a 60°cone having its center located 30°from the horizontal mounting surface of the point source and in line with the track direction. For sources which are required to be viewed vertically (i.e., the vertical LLL marking up to the door handles) the intensity distribution shall be within a 60°cone having its center located perpendicular to the mounting service of the point source. Spacing between sources shall be not more than 300 mm. See Annex G - G.1 and G.2.
4.3.3 The power supply arrangements to the LLL system shall be arranged so that a single break in the supply cabling does not result in the system becoming ineffective.
NOTE This requirement can be achieved by using at least two battery power supplies in each single main vertical fire zone or by using fire resistant cables in accordance with IEC 331 from the emergency switchboard to the input of the LLL system.
4.3.4 EP systems shall meet the relevant requirements for emergency luminaries in accordance with IEC 598-22-2 when tested at a reference temperature of 40 ℃.
4.3.5 EP systems shall meet the requirements for vibration and electromagnetic interference in accordance with IEC 945.
4.3.6 EP systems shall provide a minimum degree of ingress protection of at least IP 55 in accordance with IEC 529.
4.3.7 EP materials shall be flame retardant in accordance with IEC 92-101.
4.3.8 Entire systems, including those that are automatically activated or continuously operating, shall be capable of being manually activated by a single action from the continuously manned central control station.
4.3.9 EP materials shall be tested in accordance with Annex D.
5 Technical product documentation
5.1 The technical product documentation for LLL systems shall comprise the following documents：
- Installation plan, which should include the wiring layout and contain examples of the details of LLL signs, markings, and arrangements;
