Have you ever felt the panic of being suddenly engulfed in darkness in a public place? It’s one of the worst nightmares any airport can experience, especially when caused by a massive power outage. When the lights go out, air traffic halts, ticketing stops, everybody loses money, and passengers get upset. The costs add up quickly for air carriers and the airport, not to mention potential safety issues that arise when you have masses of people stuck in the dark.
Consider the power outage at Hartsfield-Jackson Airport in Atlanta in December. Electricity throughout the airport was lost on a busy pre-holiday Sunday, grounding air traffic, creating a ripple of delays of across North America. The outage lasted nearly 11 hours, caused by an electrical fire in a tunnel under the airport that crippled both the main power system and its backup. Such a power outage becomes expensive in any number of ways, for example, airlines can accrue fines up to $275,500 per passenger for any domestic flight stuck on the tarmac for more than three hours. Delta Airlines alone estimated that the December power outage cost them $50 million.
Unfortunately, these things happen, and they seem to be happening more often; earlier this year the Consumer Electronics Show was disrupted when the power in the Las Vegas Convention Center failed for two hours. Clearly, any airport can lose power at any time and it’s up to airport management to be prepared for the worst, especially when it comes to passenger safety. So, what can we learn from the power outage at Hartsfield-Jackson? And how can we better prepare for future outages?
Plan for the Worst
Every airport needs to have built-in power redundancy. Although Hartsfield-Jackson did have alternative power in place, the fact that the backup system was adjacent to the main power system created a single point of failure for both primary and backup electricity. Other airports are designed to address this problem. O’Hare, for example, is serviced by multiple substations, thus reducing the chances of a total power failure. Having physically distributed backup power systems functioning as isolated units minimizes risk of an outage from a single point of failure. Of course, these systems need to be routinely checked to ensure correct operation.
It’s also important to have an emergency plan in place to deal with a power outage, including well-documented procedures and regular staff training. When the power systems fail, airport personnel need to know how to respond to promote passenger safety. Typically, that means one of two options: have a plan of egress to provide sufficient light to get people out of the building, or provide a strategy to shelter in place. In either case, you need to have backup lighting in the event of an emergency.
The challenge is that many airport emergency systems, including lighting, are aging and out of date. For decades, emergency lighting has relied on standalone exit signs and emergency lights often powered by centralized batteries. However, as safety regulations have changed, new technology has enabled new solutions. Emergency lighting systems have evolved to enable new lighting strategies that can be customized for any type of power outage, and new emergency lights can be readily retrofitted into older lighting systems.
New Strategies for Emergency Lighting
While lighting technology may continue to advance, the basic purpose of emergency lighting remains unchanged – to provide sufficient illumination to allow people exit to safely in the event of an emergency. Safety regulations require a minimum amount of light for a preset period of operating time – usually between 90 and 180 minutes, depending on local regulations – to ensure a safe exit.
What has changed is the types of emergency lighting available. Emergency lighting is moving away from halogens, fluorescents, and other types of lights and beginning to standardize on LED luminaires. LEDs offer a number of advantages for emergency applications: they are low energy so they can run longer on less battery power; they are highly reliable and heat resistant so they are less prone to failure; and they can be easily installed almost anywhere, including being retrofitted into existing luminaires.
Using LEDs for emergency lighting also makes it easier to stay compliant with changing building regulations. LEDs can be programmed with different lighting characteristics, and even programmed with different power profiles for different applications. For example, most safety standards demand a minimum of 90 minutes of light in the event of an emergency, but larger structures, such as skyscrapers and airports, often are required to have longer illumination periods, often up to 180 minutes. With programmable power, the same LED units can be adapted for use throughout an airport and tuned to meet specific installation requirements.
Understand the Safety Codes That Apply
Before you can choose the right types of emergency lighting, you need to know what emergency regulations apply to your airport and your region. Each state and municipality has its own building codes for emergency lighting.
In New York City, for example, emergency lights are required to be encased in steel housings and illuminate all potential exits illuminated, not just those that are part of an exit plan. New York also requires a minimum of 2 fc (foot candles) of illumination at floor level; higher than the national building code which requires only 1 fc. Chicago has a different set of emergency lighting standards, and even requires emergency lighting during a brownout (i.e. when the power drops below 10 percent). Different regions also maintain different regulations for public buildings versus commercial buildings, with different illumination times and intensities based on the estimated time it takes to exit the building.
The National Fire Protection Association (NFPA) has its own set of building safety codes. NFPA 101: Life Safety Code, for example, requires emergency illumination for all buildings including lighting stairs, aisles, ramps, corridors, escalators – any path that can lead to an exit. The NFPA also requires emergency lighting to illuminate within 10 seconds of a power failure. Battery-powered lights have to provide 1 fc of illumination for a minimum of 90 minutes. After 90- minutes the requirement drops from to a minimum of 0.6 fc (0,65 lux).
When assessing your emergency response strategy, be sure you know what specific regulations apply for your airport. The fines for non-compliance can be expensive.
The Need for LED Emergency Lights
One common characteristic of all emergency lighting standards is that they require battery backup; as the outage at Hartsfield-Jackson shows you can’t rely on centralized backup power. One of the trends we are seeing in emergency lighting is battery power migrating away from a central battery source to self-contained emergency lights.
Central battery power for emergency lighting does simplifies maintenance and testing. It also tends to provide a stable environment so factors such as high and low temperatures don’t affect battery life. However, centralized batteries for emergency lighting tend to be expensive when the higher cost of the batteries and the wiring needed for a large structure are considered. Centralizing battery power also requires maintaining a large battery room with additional cooling. And it presents a single point of failure if a circuit or connection fails.
With the cost of solid-state lighting continuing to drop, self-contained LED emergency lights are proving more versatile and more cost-effective.
LEDs are more compact, so they can be installed anywhere, including being retrofitted into existing light fixtures. A growing trend in facilities is to install small LED light bars in fluorescent fixtures to provide emergency lighting. Their compact size and lower power requirement mean LED emergency lights can use smaller batteries, so they can be retrofitted into existing light fixtures; no new luminaires required. The LED emergency lights also can be programmed to deliver 90, 180, or even 360 minutes of illumination.
Battery technology is advancing as well. Lead-acid batteries are being replaced by nickel-cadmium batteries that are smaller, lighter, easier to recharge, and last longer. Manufacturers also are introducing higher capacity lithium iron phosphate batteries for use in emergency LED lighting. Most batteries last from five to 10 years and are easy to swap out without having to replace the entire light fixture.
Many emergency LEDs have indicator lights to show the status of the unit; an important consideration since most regulations require periodic testing. These emergency lights can be tested manually, or they can be wired to a central controller to monitor battery life and readiness. Some newer models offer a self-diagnostic feature, running a test monthly for unit health, and displaying an easily noticed red light if there is a problem. Janitorial staff or anyone noticing the red light can then raise a maintenance issue. Linking programmable LED lights into a single infrastructure simplifies monitoring and management, but the lights still operate independently, eliminating risk from a single point of failure.
After the Hartsfield-Jackson Airport power failure, managers should be rethinking their emergency procedures including upgrades to your emergency lighting. Talk to your maintenance team, your electrical suppliers, and your contractors about the current state of your emergency lighting. It might be time to upgrade to LED emergency lights through an easy retrofit or as a part of new construction. Either way, LEDs are a worthwhile investment to ensure your airport complies with the latest safety regulations, and that you are prepared the next time the lights go out.
Russ Sharer is Vice President of Global Marketing and Business Development for Fulham Co., Inc., manufacturer of innovative and energy-efficient lighting sub-systems and components for lighting manufacturers worldwide.
