Emergency lighting: standards, practice and maintenance

Emergency lighting is lighting that serves as a backup. The emergency lighting fixture will remain lit or will activate to illuminate if the mains power is lost. What standards apply to emergency lighting and how does it work in practice?

People often establish a direct relationship between emergency lighting and fire safety. This is partly because enforcement is generally a task of the fire service. However, it is a great misunderstanding that emergency lighting is primarily intended for safe escape in the event of a fire. Only when a fire results in a power failure can emergency lighting provide a life-saving function. Emergency lighting allows you to safely leave a building in the event of a power failure, regardless of the cause.

Emergency lighting rules and standards

The Working Conditions Act and the Building Decree 2012 form the basis for the design and maintenance of emergency lighting. The 2012 Building Decree looks at the function and use of the building. The building owner is responsible here and the municipality often has a controlling function. Within the framework of the Working Conditions Act, the Working Conditions Decree is in force. The employer is responsible for this.

Emergency lighting is one of the necessary provisions, as it enables the safe use of escape routes and emergency exits.

• For emergency lighting, the European standard NEN-EN 1838: 2013 applies. The standard applies to buildings to which the public and employees have access.
• This standard again refers to NEN-EN-IEC 60598-2-22, which describes the requirements for lighting fixtures.
• NEN-EN-ISO 7010 describes the safety symbols and colors, including the globally accepted and accepted pictogram for escape route indication.
• NEN-EN 50172 contains regulations about emergency lighting, the design of an emergency lighting installation, the choice of a system, its maintenance and the recording of information. The standard contains many references to NEN-EN 1838.
• NEN 1010: Safety provisions for low voltage installations contains, in addition to technical implementation requirements, specific requirements for medically used areas.
• NEN-EN 50171 defines the general requirements for centrally supplied emergency lighting systems. The construction and installation of systems are described in detail.

Types of lighting

1. Stand-by lighting (also known as replacement lighting)

Replacement lighting is full-fledged lighting that switches on in the event of a power failure and ensures that normal activities can be continued under virtually unchanged conditions. It is not primarily safety motives that apply here, but technical or economic arguments.

2. Emergency evacuation lighting

Emergency evacuation lighting is a provision for people who have to leave a location immediately due to a calamity and subsequent power failure or – before they can leave – first have to close a (dangerous) process.

Emergency evacuation lighting can be divided into:

Escape route lighting

Escape route lighting ensures that escape routes and any obstacles on the route can be clearly recognized, so that a building can be safely exited. Luminaires for escape route lighting must be able to produce at least the desired brightness within 15 seconds after a power failure. In areas with an increased risk, a time frame of 0.5 seconds applies. The color rendering index (Ra) of a light source must be at least 40. Otherwise people will not be able to recognize the green safety colors of the escape route properly.

Flight route indication

Escape route markers mark the escape route, are permanently illuminated and can be recognized by pictograms and colors that indicate how a building or structure can be left. The relevant pictograms and colors are described in detail in the NEN-EN-ISO 7010 standard.
When it comes to the escape route indication, luminaires must meet established visibility requirements within 15 seconds after the power failure. These are as follows:
– The colors are in accordance with ISO 3864.
– The luminance of each part of the security color is at least 2 cd / m2
– The ratio between the maximum and minimum luminance within both the white area and the safety color does not exceed 10: 1.
– The ratio of the luminance L white to the luminance L safety color must not be less than 5: 1 and not greater than 15: 1.

Anti-panic lighting

In the event of an emergency, the anti-panic lighting enables people to reach a place from which they can continue to use an escape route.
This emergency lighting is achieved through a horizontal illuminance of at least 0.5 lux on the floor, so that people can safely reach the escape route. The 0.5 lux does not apply in an edge zone of 0.5 m from the area.

Lighting for workplaces with increased risk

Lighting for workplaces with increased risk is there for the safety of persons who, as part of their work, are responsible for (dangerous) processes or who may find themselves in a dangerous situation. The lighting enables them to carry out a correct closing procedure so that the safety of other people in the building is not compromised. For emergency lighting of workplaces with an increased risk, the following applies: a minimum illuminance of 15 lux on the floor and at least 10 percent of the normal illuminance

This emergency lighting must be placed at:

– every exit door for evacuation
– all stairs where each step receives direct light
– any level change
– every escape route indication and emergency exit
– any change of direction of the escape route
– any crossing of corridors
– the evacuation exit
– the first aid post (5 lux)
– any fire extinguishing facility or fire alarm point (5 lux)

The required 5 lux only applies if these facilities are not located in an escape route or anti-panic area.

Central or decentralized power supply system

Decentralized emergency lighting

Decentralized emergency lighting consists of luminaires with a built-in battery and a charger, which are directly connected in all rooms to the constant power supply of an end group for the lighting. The decentralized installation does not depend on the cable infrastructure in the event of a power failure due to the built-in battery.

Decentralized emergency lighting always needs a constantly supplied phase and neutral (230 Volt) and is, if possible, connected to the power supply of the lighting groups in the room concerned. Many decentralized emergency lighting luminaires can also be connected to a switched phase. In this way they ‘hitchhike’ with the normal lighting.

Electric escape route signage with gray emergency lighting

Centrally powered emergency lighting

Centrally supplied emergency lighting consists of luminaires that do not have their own power source and charger. The luminaires are supplied directly from a central emergency power system. This makes the emergency lighting installation dependent on the cable infrastructure in the event of a power failure. To be on the safe side, these systems therefore often have several central emergency power supply systems and / or substations.

Central emergency lighting is connected directly behind an emergency power supply system or substation. The central emergency power supply system is installed in accordance with the requirements of the NEN 1010 standard. When laying the cable infrastructure, the cabling and sealing between various fire compartments must be taken into account with regard to the central emergency power supply system. It is important that a possible fire in one fire compartment does not adversely affect the emergency lighting in other compartments.

There is no ‘better’ or ‘worse’ emergency lighting system. Depending on the requirements and circumstances, there is a ‘more suitable’ system. The choice between central and decentralized emergency lighting involves the following factors:
• The desired security level
• The height of the various spaces
• The ambient temperature of the various rooms
• The required light output in case of calamities
• The options for maintenance

The emergency lighting must switch on in time and continue to function for the prescribed time. In the event of a fire, the emergency lighting must operate for at least as long as the time set for the evacuation of the building. Usually this is 30 minutes. In the event of a power failure due to a cause other than fire, the emergency lighting must remain on for at least 1 hour.

Step-by-step plan for the installation of emergency lighting

Before installing emergency lighting, the advice applies: make an inventory first! A step-by-step plan will give you a good idea of the risks in and around a building. Then you can work out an emergency lighting plan.

The step-by-step plan based on NEN-EN-1838 provides a systematic approach to the practical design of an emergency lighting installation. It provides a good picture of the risks inside and outside a building and of the escape options.

1.) Mapping the building: living areas, escape route and workplaces with increased risk;
2.) The escape route indication;
3.) The escape route lighting, anti-panic lighting and lighting of workplaces with increased risk.

Emergency lighting maintenance

Emergency lighting installations must be inspected at least once a year and is intended to determine whether the system meets all requirements. The inspection includes an assessment of the technical condition of the installation, but just as important is the determination that the system is geared to the actual use of the building. The inspection is a baseline measurement prior to the periodic maintenance, which guarantees that the system will function properly again for at least one year. ISSO Publication 79 serves as a guideline for the inspection and maintenance of an emergency lighting installation. This guideline meets the requirements of the Building Decree and the Working Conditions Act.

When all preparations have been made and agreements have been made with the client, the actual inspection can begin. The following documents are required for this:
• Current scale drawings of the building in which the emergency lighting is projected
• Evacuation drawings – to determine what the escape routes are
• Reports of previous inspections
• Log of the performed maintenance
• Reports of risk inventories and evaluations with regard to high-risk workplaces and / or emergency lighting
• Any other documents

The starting point for the periodic maintenance is consultation of the most recent inspection report and the logbook containing the description of the activities of the previous maintenance visit. The logbook should also contain the most recent drawings of the installation. There may be any outstanding issues or recommendations that need to be addressed during maintenance. If no logbook is available, it is sensible to advise the client to inspect the system first. If this is not feasible, the available documentation is the starting point. It is very important that all activities are systematically carried out and documented.

If not all necessary documents are available, this should be stated first in the inspection report. It is also important to indicate how much influence the absence of certain documents has had on the inspection, for example in the identification of risky workplaces. Insofar as statements or conclusions on this point are based on personal experience and expertise, this must be reflected as such in the report.

The first impression of a system is often telling. As a rule, it is easy to see whether an installation has been properly maintained or whether maintenance has been overdue. Separately, six questions are answered during the inspection:

• Does the emergency lighting system still fit with the use of the building?
• Has specific risky situations been sufficiently taken into account?
• Are the products used satisfactory?
• Has the emergency lighting been installed correctly?
• Is the required light level being achieved?
• Do the luminaires achieve the required burning time in an emergency?

The following activities are carried out during maintenance

Corrective maintenance

By corrective maintenance we mean the replacement of worn or otherwise damaged parts, such as discolored pictograms, damaged housings, defective circuit boards, light sources and batteries. When the battery has been defective for a longer period of time, there is a real chance that the electronics have also been affected. It has (possibly) tried to charge a broken battery for a longer period of time and is therefore aging quickly. If this is the case, the electronics will break down shortly after replacing the batteries. If it is suspected that the battery has not been good for some time, it is recommended to also replace the printed circuit board or the entire fixture. Defective luminaires can be presented to the supplier for repair. Depending on the age of the luminaire, they can also be replaced with a new one. Make sure that the photometric properties match the design of the system.

Preventive maintenance

Replacing the light source
As a rule, a fluorescent tube is replaced once a year. We assume 8,400 burning hours per year. Fluorescent tubes are available with a different number of burning hours. Incidentally, the effect can never be guaranteed for a whole year. The life span varies widely and it is common for some of the tubes used to die prematurely. For luminaires that only switch on in an emergency, a preventive replacement once every four years is sufficient. When replacing the light source, also check the contact points and replace if necessary. A lifespan of 5 to 10 years or even longer applies to LEDs. Consult the manufacturer’s manual for this. LEDs do not break easily, but give less and less light over time. There are two options here: opt for preventive replacement or determine by means of light measurements whether the performance still meets the values stated in NEN-EN 1838.

Replacing the battery
The battery is generally preventively replaced once every four years, unless otherwise specified by the manufacturer. Only use batteries specified by the manufacturer for this purpose. Emergency lighting batteries must meet strict international requirements to ensure operation for a longer period of time. The reliability of the battery deteriorates sharply after the aforementioned four years and operation can then no longer be guaranteed until the next periodic maintenance. The life of batteries in central power systems depends on the type of battery chosen. Consult the manufacturer’s documentation for this.
The cleaning of the fixtures
Cleaning of fixtures is done with suitable cleaning agents. A cloth or brush is often sufficient, but in specific situations a cleaning agent is recommended. If in doubt, consult the manufacturer’s maintenance instructions. Cleaning has a preventive effect
operation and contributes to the reliability and service life of the system.

Reporting
The maintenance report describes the findings. This concerns matters that require extra attention or are important for the next periodic maintenance. If immediate action is necessary, this should be described. This may concern luminaires that have to be sent to the supplier for repair, ordering parts or luminaires to be new. It must also be clear who is taking the action and when this must have happened. The maintenance report is recorded in the log so that the customer and the controlling authorities can see which actions are still open.

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