Richard Caple, immediate
past President of the Society of Light &
Lighting (SLL), and Lighting Applications
Manager, Thorlux Lighting.
While not a significant factor in this particular event, emergency lighting has become a focus of attention for many building owners, occupiers and employers. An event of this scale highlights and reminds everyone of the importance of providing, testing and maintaining effective life safety systems. Emergency lighting is a critical life safety system but providing a compliant solution is often time-consuming, complex and expensive. To quote a colleague: “often just enough is done.” But is “just enough” enough? Emergency lighting must follow a process of consultation, collaborative design and rigorous maintenance and testing.
One of the most important parts of emergency lighting is consultation. Without communication between all of the relevant parties, those responsible for the design of a system stand very little chance of producing a compliant scheme. The consultation phase creates the forum for key stakeholders to engage and develop a better understanding of the type of building, its intended use, the type of people using it, periods of use, risks and emergency strategies.
These are all important factors and are identified in IS3217:2013 + A1:2017. Often, however, these consultations do not take place. This leads to assumptions and estimates, which in my experience are often never reviewed or questioned, potentially leading to an ineffective system.
The type and number of stakeholders involved in the consultation will depend on the nature of the project. For example, if it is a new building or the refurbishment of an existing one, the size and scale of the building will also dictate those who should be involved. At the very least the building owner, occupier/employer, building services engineers, architects, electrical engineers and lighting designers should be communicating to deliver an affective and appropriate emergency lighting solution.
The role of emergency lighting has also become more complex, which further increases the importance of consultation. Not only is emergency lighting required to facilitate the safe exit of people from a building, high risk emergency lighting is needed in areas where potentially-dangerous equipment is being used, or a process needs to be made safe before evacuation.
A new consideration on the horizon is safety lighting or “stay put” as it is also known. In some situations there may be a greater danger from evacuating people out of the building or there may be situations where mains power fails to the building but this poses no danger to the occupants. Therefore, certain tasks might be carried on, but a sufficient amount of light needs to be provided, which may be much higher than normal emergency lighting levels. System design then becomes very important. Safety lighting also needs rigorous consultation between all parties to produce a policy and to ensure that the system is sufficient and safe.
Once all of the impacting factors have been identified within the consultation, the design process can start. Aside from the requirements of escape lighting to routes and anti-panic lighting to open areas, illumination is needed at the points of emphasis, such as changes in direction or level, as well as the highlighting of fire alarm call points, firefighting equipment, first aid points and fire alarm panels. The requirements can become more complex for large buildings, high-rise buildings or buildings where the mobility of people may be impaired, such as hospitals or care homes.
The level of potential complexity that the designer needs to consider highlights the importance of not only ensuring the competency of the lighting designer, but that they also have access to the relevant information. It must also be remembered that emergency lighting is covered in an array of different standards, which from time to time are updated. Is the designer conversant with the latest requirements? How do they prove that they are? Is it time for professional competency recognition for emergency lighting designers? These are some of the questions that are starting to be asked by many within the lighting industry.
Maintenance and testing
One of the most costly elements of emergency lighting is the testing and upkeep of a system. I have seldom come across buildings that have records demonstrating proper testing, and also important, records of maintenance being carried out showing rectification of failed or faulty emergency luminaires. To fully test and log emergency lighting in compliance with the standards is expensive, with labour time being the significant factor.
Quarterly short duration tests are required to prove the system is operational with a full rated duration test being required every year. The full rated duration test is often the most costly and problematic, as consideration is needed as to what happens after the luminaire has been fully discharged. Most manufacturers will recommend a full 24-hour charge before the luminaire is effective again and at full capacity. Therefore, managing these tests – while still keeping a building operational and safe – can be a challenge. Often to do this involves testing alternate luminaires at different points through the year, meaning multiple visits to a site. This raises costs further. However, one thing is clear, not testing and maintaining emergency lighting is a sure way of contributing to the system not functioning correctly when it is really needed.
Advances in technology are helping to overcome some of the problems associated with emergency lighting compliance. LED technology, for example, has been hugely beneficial. Emergency lighting products have become much smaller and more discreet, while the output and optical performance has improved significantly. These improvements allow for much wider spacings and consequently a reduction in the number of emergency luminaires required. Better lamp and battery life is also reducing maintenance costs.
Another significant advancement in emergency lighting is self-test, communication and reporting systems. In fact, Autotest systems, where the luminaire tests itself to the requirements of the standards, have been around for a few decades.
However, today’s communicating and reporting technologies, which provide enhanced status and condition information, make the management of emergency luminaires much simpler, as well as lowering life costs. Building owners/maintenance managers now have the facility to see the status of all of their emergency luminaires within a building, or even multiple buildings, on their computers, or mobile devices.
Importantly, these systems can also be proactive, providing instant details of any fault. Through manual testing a problem may develop with a luminaire shortly after test, meaning it could be a whole month before the fault is identified at the next test. Today’s systems also have the ability to tell you what has failed, for example a battery or lamp, and to display where the fitting is in the building. This reduces labour
time for remedial works.
With battery replacements typically being required every three to six years, this is the most common regular maintenance needed. A proactive system can not only tell you when a battery has failed, but also identify batteries that are about to fail, again reducing the overall call out rate and maintenance cost for a building.
A further advantage of these automatic systems is the ability to schedule tests. Either random testing can be carried out, ensuring that no one area will be completely without emergency lighting due to depleted charge in the batteries, or it can be scheduled for the whole building to be tested at once, for example on Christmas Day when the building is not being used. Batteries then have time to charge. This ensures full capacity when the building is re-occupied, thus mitigating risk to the occupants.
Emergency lighting is a life safety system, and it must be taken seriously. Getting it right is important, and involves a process of consultation, competent design, careful consideration of system type and robust maintenance and upkeep. It remains to be seen as to what will happen to building regulations following the events at Grenfell Tower. However, we all have a part to play, and it is up to us to ensure that our buildings are safe for people to live, work and play in.