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A discussion on issues related to fire emergency lighting systems may be helpful to everyone! Fire emergency lighting generally consists of three functional systems: a fire operation lighting system made up of emergency lighting fixtures, which is designed for firefighters and rescue personnel; it is usually installed in important locations such as power generation and distribution rooms, fire pump rooms, fire control centers, and communication centers. Its operational time during emergencies should be no less than 90 minutes, and it must meet the requirements regarding normal operating illumination levels ； The fire evacuation function system, which consists of fire emergency evacuation lighting fixtures, is installed to provide the necessary illumination for personnel evacuation; it is generally placed in public corridors and vertical stairwells. Its emergency operation time should be no less than 90 minutes, with an illumination level of no less than 0.5 Lx ； The emergency evacuation signage system, which consists of low-level fire emergency evacuation lighting, evacuation indicators, and other types of signs such as photoluminescent signs, provides clear guidance on the directions and routes for evacuating people. It is generally installed in the public corridors and vertical stairwells of large public places with high foot traffic, such as shopping malls and cinemas, usually at ground level or within 1 meter above the ground. Its operational time in emergency situations should be no less than 90 minutes, and the surface brightness of the sign lights should be at least 15 cd/m2. ??During routine fire safety inspections, attention should be paid to the following issues regarding the fire emergency lighting system. 1 The emergency lighting fixtures do not use a dedicated power supply circuit; instead, they are connected to the regular lighting circuits that are not designated for fire protection purposes.??(1) Article 11.8.9 of the “Code for Electrical Design of Civil Buildings” stipulates that: “For emergency lighting fixtures equipped with batteries for use in evacuation purposes, the normal power supply can come from a dedicated circuit in the distribution panel of that floor (or area), or it can be drawn from the disaster prevention-specific distribution panel of that floor (or area). That is, when using emergency lighting fixtures with batteries for evacuation lighting, their power supply should preferably come from the dedicated disaster prevention distribution panel on that floor (or area). If such conditions are not available, it is acceptable to use the sub-distribution or main distribution panel on that floor (or area), but a dedicated circuit must be provided; in other words, its power supply circuit should not share the same circuit as non-firefighting power supplies. If the batteries for emergency lighting strips can be connected indiscriminately to the normal lighting power supply in that floor (or area), then in the event of a fire when non-firefighting power supplies are cut off, the emergency lighting fixtures will not receive a reliable power supply and will therefore fail to function. For example, in the Dongba branch of Guangyuan Jihui Supermarket, the nearly 30 fire emergency lighting fixtures with built-in power sources were all connected to the regular lighting circuit. When the business is closed and the non-fire-related power supply is turned off, the batteries in these emergency lighting fixtures come online; however, they do not receive any charging once power is cut off. In the event of a fire, these emergency lighting fixtures are unable to perform their function ； Furthermore, if the battery of an emergency light is charged and discharged every day, it will cause significant wear and tear on the battery, accelerating its eventual failure. ??(2) For fire emergency lighting in areas that need to remain operational during a fire, such as power distribution rooms, fire pump rooms, fire elevator machinery rooms, fire control rooms, smoke exhaust machinery rooms, generator rooms, and main telephone switching stations, this lighting can be supplied by the fire emergency power distribution panels located on each floor (or area) ； The normal and emergency lighting in these areas can also be powered by two independent dual-power supply systems (or two circuits), one in use and one as a backup, which are fed by the power supply intended for fire-fighting purposes, and an automatic switch-over device is available for these systems ； Or without automatic switching between two power sources, the normal lighting and emergency lighting are each connected to separate circuits, one in use and one as a backup. Backup lighting should ensure normal illumination; emergency lighting generally uses batteries as a backup power source to provide transitional lighting during power supply transitions. ??(3) To avoid confusion in the design phase regarding fire emergency lighting, it is recommended to design fire emergency lighting separately from normal lighting. This facilitates reading the drawings, construction, and fire safety design reviews, as well as makes it easier to correct any errors or omissions, thus ensuring the quality of the project. 2. Overstating the capabilities of photo-luminescent signs, and using such products in any setting without consideration for the appropriate environment. Photo-luminescent signs are light-storing signs made from rare earth materials. At the current level of technology, when exposed to sunlight or fluorescent light sources for more than 10 hours, its surface maximum brightness can reach 3–5 cd/m2; however, this brightness lasts only a few minutes before declining to the millicandela range and remaining at that level for several hours. In environments with very low light levels (typically no more than 1 Lx), its graphic symbols can still be displayed, but it can no longer ‘actively’ draw the eye’s attention. Such signs must be equipped with appropriate lighting sources to ensure that they are illuminated before a fire breaks out, thereby allowing them to accumulate more light energy. ??According to the test report provided by the **Fire Testing Laboratory, photoluminescent signs cannot capture people’s attention in areas with an illuminance of more than 1 Lx, as their surface brightness is low ； In the presence of smoke, it can only be faintly seen from close range. People crawling forward can serve as a guide, but such markers must be placed continuously as much as possible; otherwise, any gaps in their placement will render all efforts pointless. ??In the event of a fire that causes the normal lighting to fail, it is necessary to ensure that the evacuation lighting activates simultaneously, with the illuminance in general areas remaining at least 0.5 Lx; in crowded areas and vertical stairwells, this level should not be lower than 1 Lx, in order to enable people to escape safely and quickly. While providing evacuation lighting, there must be clear signs to guide people quickly to the exits; whether there is smoke or not, such signs must immediately catch people’s attention. Therefore, emergency lighting should be provided by fire emergency lights, rather than relying solely on photoluminescent signs. Furthermore, photoluminescent signs are only beneficial to those crawling their way out during the later stages of a fire (that is, after 90 minutes when the evacuation lighting lights go out), and they serve merely as auxiliary signs for use in conjunction with fire emergency lighting. 3 The installation of emergency lighting fixtures does not meet the requirements. ??(1) Civil emergency lighting fixtures are used in place of fire emergency lighting fixtures; fire emergency lighting is not installed in areas where a large number of civil emergency lighting fixtures are used ； Civil emergency lighting fixtures do not have the capability to function properly in fire conditions, and their protection rating is lower than IP20 (the cover material is a non-combustible material or a difficult-to-burn material with an oxygen index of over 32) ； ??(2) The evacuation indicator lights on the passages are installed near the ceiling, and at corners the direction indicated by the signs does not match the direction of the exits, etc ； ??(3) In areas such as fire control rooms and fire pump rooms where operations must continue in case of a fire, the emergency lighting does not meet the required illumination levels for proper operation. 4 Emergency lighting fixtures with built-in power sources can operate continuously for about 20 minutes, after which the illuminance gradually decreases to zero ； They are used for frequent charging and discharging; if proper maintenance is not carried out or if there are problems with the power supply lines, they can easily get damaged. 5 The selection of emergency lighting fixtures does not take into account the actual characteristics of the building. During fire safety inspections, it was found that the vast majority of buildings use independently controlled emergency lighting fixtures with their own power sources. For large buildings with large crowds, long evacuation distances, numerous evacuation routes, many turns, and complex environments, this approach is not only costly but also makes inspection and maintenance difficult, as centralized management is not possible. 6 Use a power supply of 220V or higher as the power source for emergency lighting. A 220V urban power grid supply as well as generator sets are used as emergency power sources. Different from ordinary fire protection power distribution systems, fire emergency lighting fixtures are installed in many locations, with pipelines arranged in various directions; most of these fixtures are located within ceilings. In the event of a fire, ceilings can easily be damaged, leading to broken pipelines and shattered fixtures. If the sprinkler system is operating at this time and a large amount of water is injected into the floor, the 220V power supply could pose a life threat to those who evacuate and to firefighters, and it might also cause the fire to spread due to short circuits in the wiring of the emergency lighting fixtures. 7 The wiring installation does not meet the specified requirements. **Key codes such as the Building Code set out specific requirements regarding the protection of the wiring for fire emergency lighting fixtures: the wiring for fire-related electrical equipment should be protected by conduits, while accident lighting and evacuation signs should have protective covers made of glass or other non-combustible materials.** Fire emergency lights are installed in large numbers and over wide areas, with the vast majority of them located above the ceiling. In the event of a fire, if the pipelines break or the lamps are damaged, it is very easy to cause electrical short circuits, leakage current, or large fault currents. Emergency lighting that relies on centralized power supply has higher requirements for its wiring, as the power for such lighting comes from the main wiring in the distribution panel; any damage to that main wiring or a short circuit in a light fixture can result in the failure of all the emergency lighting devices along the entire wiring circuit. Therefore, we should strictly comply with the provisions of the Building Code, High-rise Building Code, and the national standard for Fire Emergency Lighting, and strengthen the protection of fire emergency lighting systems and power distribution circuits ； Strictly select and use **standard products and flame-retardant copper-core cables ； Ensure proper fire protection for distribution lines. When installed concealed, it shall be placed within non-combustible structures, with a protective layer thickness of not less than 3 cm. When installed openly, metal tubes should be used, and fire protection measures must be taken for the lamps’ hoses, junction boxes, and connectors ； Fire emergency lighting distribution equipment shall have distinct markings. Its distribution circuits and control circuits should be divided according to fire compartments; when the distribution circuits are installed exposed, they should be protected by metal pipes or metal trunking coated with fire-retardant paint. During engineering fire safety inspections and approvals, it is common to find that when the wiring for fire emergency lighting fixtures is installed exposed, no fire protection measures are in place. Even when the required fire protection measures are applied, the hoses, junction boxes, and connectors used to connect the fixtures are not properly protected, remaining exposed outside ； The wiring is not done in strict accordance with the instructions and control methods specified for the lighting fixtures; in some cases, the emergency lighting fixtures are even connected directly to the wiring of ordinary lighting fixtures that are connected to sockets and switches. 8. The new standard for \"Fire emergency lighting fixtures\" (GB17945-2000) has not been properly implemented. This standard came into effect on October 1, 2002, but its implementation has not been satisfactory. The Fire Department of the Ministry of Public Security has explicitly ordered that products manufactured in accordance with the previous industry standards be scrapped by 2001. Local fire safety authorities are required to strictly oversee the review and approval process of fire protection designs in construction projects, in order to prevent emergency lighting fixtures that do not meet these standards from entering the market and being put into use. However, some manufacturers of fire emergency lighting fixtures still bring products produced according to the original industry standards to the market after changing their packaging and instructions. 9 The design and construction units failed to give sufficient attention to the role and importance of the fire emergency lighting system within building fire protection facilities; during the engineering design and construction processes, no overall planning or comprehensive consideration was given to fire emergency lighting ； Alternatively, design and construction proceed simultaneously, with the installation of emergency lighting facilities only being carried out towards the end of the project or even during the acceptance phase. However, at this point, there is no choice available regarding the power supply method, control method, or product model for emergency lighting, leaving inherent risks. References: 1. Code for Electrical Design of Civil Buildings 2. Emergency Lighting for Fire Fighting (GB17945-2000)