Improving Fire Safety Protection
- By Christa Poss
- November 1st, 2005
There are many fire safety products, but by far, the most common systems are standard fire alarm sounders and detectors. Their biggest advantages are that they get people’s attention, and almost everyone understands what they mean. Unfortunately, people are so accustomed to false alarms that they often fail to immediately evacuate when the alarm sounds. Even when people do heed the warning, they cannot count on fire alarms and detectors to help them find an exit because these devices are not designed to be anything more than a warning system.
Smoke detectors do an invaluable job of alerting people to the presence of smoke and fire. However, once people know there’s a fire, it’s clear they need more information: They need to know how to safely exit the building. For example, people are aware of what a fire alarm means, but that alarm alone does nothing to ensure that people leave the burning building safely.
In numerous building fires, people have died attempting to leave through one door after bypassing other, closer exits. This happens because people do not know where alternative exits are, or in their panic, they immediately rush from the building the way they entered without looking for another exit. Unfortunately, taking a familiar route may be a deadly mistake.
Consider for a moment how quickly one can become lost, disoriented and confused during a fire emergency occurring where students call home. New directional sound technology differs from other fire/life safety systems by helping people find their way out of buildings during an emergency. Unlike standard fire alarm sounders, which simply warn people that there is a fire in the building, directional sound technology helps building occupants evacuate quickly and efficiently by informing them which way to go.
Directional sound technology uses broadband, multifrequency sounds with low-, mid- and high-range signals instead of the narrowband noise emitted by fire alarms and smoke detectors. This is a significant difference, because people cannot reliably localize narrowband noise — or in other words, they have great trouble determining the source of this type of noise. If people cannot localize a sound, then they can’t follow it to safety.
The broadband sounds given by directional sounders, which are placed at perimeter exits at ground level and stairwells in a multistory building, lead occupants toward them and clearly communicate which way to go. People intuitively know to follow these sounds and to move from one device to another until they reach an exit.
When people follow the sound coming from the closest directional sound device, they not only ensure that they will find an exit faster, but that building occupants will be more evenly divided between different escape routes. In facilities where more than one escape route and exit are marked by a series of directional sound devices, evacuees will be kept from collectively crowding a common, everyday route. Instead, people in an opposite section of a building, for example, will be directed to a secondary exit, which will reduce congestion and evacuation times for all.
Working in conjunction with smoke detectors and other audible/visible notification devices, directional sound technology consists of a series of sounders placed at perimeter exits and stairwells. The sound devices, which are tied into a building’s fire control panel and are automatically activated as soon as a sensor detects the presence of fire or smoke, deliver easy-to-understand cues that intuitively lead people to the nearest exit.
Directional sound technology offers a significant improvement over using only visual-based emergency wayfinding aids, such as emergency lighting and photoluminescent guidance strips, which can be difficult to see in smoke-filled environments. Because directional sounders lead people to exits using sounds, not words, they assist people who have visual impairments and exhibit no language barrier, such as requiring people to know a particular language to understand instructions. The devices can also be heard above other noises, including fire alarms and shouting.
By tapping into another sense that is unaffected by smoke — hearing — directional sound technology provides clear, easy-to-understand assistance for finding the nearest exit. And the added bonus is evacuations occur much faster than with other emergency egress aids, even in completely unfamiliar buildings. Directional sounders can decrease exit times in a smoke filled area by up to 75 percent and up to 35 percent in clear visibility.
CHRISTA POSS is a product marketing specialist for System Sensor . She has been part of the commercial fire detection business unit since joining System Sensor in 2001.