Emergency Doorway Identifiers

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Emergency Exit Identifiers, often called EEIs, (which are sometimes called "Emergency Doorway Identifiers", or EDI's) are fire alarm accessories which were introduced to the fire-safety and security industries in the last decade as a new technology designed to provide visual notification information to occupants of a building during a fire or heavy smoke event when the building’s emergency alarms are activated. EEI’s are small electronic devices that are mounted atop a doorway and rest on the trim that surrounds that doorway which listen for the sounds that emergency alarms (such as smoke detectors, CO2 detectors, and other emergency alarms) broadcast when triggered in an emergency event. When an EEI recognizes an audible emergency smoke detector or fire alarm sound, it uses a lineal light source (like electroluminescent wires, LED rope lights, laser light, plastic optical fibers or other lineal light source) which is routed and attached along the outer edges of the entirety of the doorway and many times along the adjacent wall baseboards on both sides flanking the doorway to brightly light the edges with a bright pulsing light. EEI’s are marketed and sold nationally and internationally through a myriad of lighting, safety equipment, security and fire protection distributors and dealers and retailers.

Unlike other devices that are designed to provide visual information in emergencies, EEI’s are cleverly designed to be inconspicuous until they are actually needed and their design allows them to blend into most existing decors. When they are activated, they are anything but inconspicuous; as they provide desperately needed bright visual emergency information in specific areas not included in other forms of emergency lighting. That is, EEI’s light all the way around the entire doorway; both, up high at eye-level AND down low; below the line or layer of smoke as a fire’s smoke billows into a room and ultimately filling the room from the ceiling down. The EEI’s visual information is provided to evacuees automatically, in those desperate critical seconds and moments early in a fire or building crisis and long before first-responders can physically arrive at the scene; when many smoke inhalation injuries and deaths occur. The device also well serves the arriving first-responder firefighters and emergency personnel as they enter and exit the unfamiliar setting to perform their search, rescue and other firefighting duties.

Two basic types of EEI's[edit]

There are two primary types of EEI’s; stand-alone battery powered EEI’s, and low-voltage hard-wired powered EEI’s with battery back-up features that wire directly into notification appliance circuitry (NAC-circuits) in mostly commercial settings. There are EEI's available that wire directly into security systems which can become a part of a household's or building's emergency systems. Most EEI's available today are "synchronized" with the local emergency strobe lights which are installed in the building. This new, integrated and synchronized approach to EEI installation far exceeds the typical strobe light's capabilities when fire strikes a building where EEI's are installed in addition to strobe lights because they not only show emergency pulses to occupants, but they also outlining the entire exit point (such as a doorway or window).

Battery operated and stand-alone EEIs[edit]

The first EEI’s released to the general public for sale, which continue to grow in popularity in the DIY market and through commercial distributors and dealers, are powered by 9 volt batteries; just like most battery operated smoke detectors. Generally, EEI’s are inexpensive relative to the benefits that they provide to occupants of a building caught in a fire. EEI designs are well thought out and are easily installed by the do-it-yourselfer homeowner or small office operator in minutes. Most EEI’s require only a step-stool and pair of common household scissors to install the devices. Because most EEI light-strands are commonly each 12’ in length, their generous length is enough to wrap the entire doorway and run along the baseboards on either side of a doorway or ample enough to install the device on a double-door.

Hard-Wired EEIs[edit]

Many versions of low-voltage hard-wired EDI’s are also available today. Depending on the needs of the particular building and specific applications, EEI’s can be powered by nearly any existing building power source; 12v, 24v, and 110v power sources are the most common and are easily configured to the EEI with the proper conversion peripherals. Because the power source is constant in the hard-wired EEI, the devices offer a litany of additional sensing and detection functions in them or as connected peripherally with them. These hard-wired versions of their battery operated cousins are especially effective in institutional, commercial and industrial settings, can be synchronized to flash together simultaneously and can be integrated into other fire protection and security systems.

Just like their cousins, when activated, especially in darkening and smoky settings, hard-wired EEI’s automatically trigger to brightly light the outer edges and nearby floor areas or pathways on both sides of an exit doorway to highlight the entire universally recognized outline shape of your doorway with its emergency pulsing light. These devices are an important part of planning for fire in any commercial or private residential setting where employees are present or in residences where senior citizens, the visually impaired, the hearing impaired or children are present and/or sleeping such as day care facilities, nursing or assisted living facilities, lodging & hotel establishments and apartments. The visual information that they provide very early on in the crisis and in low areas, well below the smoke layer in a fire, are invaluable to those whom might experience difficulty or physical impairment in navigating to safety in a fire.

An overview of the technology[edit]

EEI’s can include a micro-controller (microprocessor) which executes and operates firmware (software program(s)) which is/are designed to perpetually search the nearby airwaves for frequency signals that are broadcast by common alarms and or to recognize other physical or electronically generated stimuli which the EEI is programmed to seek. Many (most) common smoke alarms broadcast a specific range of tones (or high pitched siren sound) at a specified frequency ranges and at a minimum volumes pursuant to current adopted fire codes and ordinances. EEI’s have an embedded microphone or other means through which these smoke alarm tones are received and processed through the device. When received, the device’s programmed software logic triggers the device to perform certain functions, such as energizing the device’s luminaries (often called light-strands). In many EEI's, when they are alarmed, the energized light-strands create a light which often flashes, or pulses. This light typically outlines a doorway and areas near the doorway and/or a pathway with the linear light emission. The device’s emitted light typically is designed to brightly highlight the outer edges of and floor areas or pathways near an exit doorway, porthole or other discharge in order to provide evacuees with visual information about where the exit door is and where they might go to escape to safety.

A Door is a Universally Recognized Shape and Destination in an Emergency[edit]

The purpose of the current common EEI configurations of their electronic components, types of luminaries, uninterruptible power sources and designs are selected based in innovational purpose, product reliability, linear luminary capability and user-friendly convention and aesthetics. While these devices can be configured to do many things, a common theme among all configurations is to provide an evacuee in a building crisis like power failure, earthquake, noxious gas emission, fire or heavy smoke events, etc. with the clear visible “universally recognizable doorway location and shape information or a pathway demarcation that leads to an exit”. Using EEI’s promotes and enhances evacuee’s ability to identify and subsequently know where to go to pass through an exit to safety in a building crisis.

Purpose of the “Lineal” Luminary in the EEI[edit]

The use of lineal light sources is key to the effectiveness of EEI’s. While people usually think of conventional light sources in terms of shedding light on an area, lineal light sources that envelope the periphery of an object, such as a doorway in the case of an EEI, is key to quickly disseminating the information about what something is (a door in the case of an EEI), where it is located and, most importantly, where to go in an emergency. Conventional lighting such as down-lights and exit signs above commercial exit doorways are often the very first light to disappear or be obstructed when smoke fills a space or a room. As smoke fills a room, its nature is to fill it from the ceiling down; this is just nature’s design. Maintaining visible a visible form of light at floor level, below the layer of growing smoke in a fire is of tremendous importance and if this light is lineal in nature, its ability to convey an objects (such as a doorway) location of great importance to evacuees. Lineal light sources of many types and vary forms are used in EEI technology and configurations as they provide the device with the capability to seamlessly outline the “entire universally recognized shape of the doorway location and structure. Unlike conventional exit signs, strobes or other visual marking devices that are commonly available in the marketplace, the EEI sheds lineal and area lighting in areas most prone to assisting evacuees where and when current visual notifying devices do not or cannot by virtue of their design.

About Color and the Human Eye[edit]

It is widely known and accepted that green based wavelengths of light, like most EEI’s emit, are the easiest colors for human’s visual systems to detect, especially in dark or darkening settings. However, as an interesting twist, it is also widely known that, at reasonable levels of illumination such as those light levels that are broadcast by EEI’s, the human visual systems don’t really see color, per se, they just see the presence of light. EEI’s are designed with this in mind and, by design; EEI’s embody the benefit of both.

It is also well established that the human eye can see over 10 million colors. The human eye is most sensitive, however, to light emitted at a wavelength of 495 nm. That wavelength (495 nm) is precisely halfway between green and blue in the color spectrum; exactly where the typical EEI light color falls. This area of the color spectrum is most visible and easiest to see (for the human brain to process) because this color actually demands the least amount of energy by the human eye to see and process the light. This is especially true in a contrasted setting in a dark or darkening volume of space; such as in a building space filling with smoke. In fact, consideration of human color visual sensitivity has led to drastic changes in the long-standing practice of painting emergency vehicles, such as fire trucks and ambulances, entirely red. Although the color (red) is intended for the vehicles to be easily seen and responded to, the wavelength distribution is not highly visible at low light levels and, actually, can appear nearly black in the evening or at night. An EDI’s light pulse (typically 2 Hz) and its color is uniquely designed to catch the attention of human eye in a crisis situation; particularly at night or in a dark or darkening (contrasted) volume of space and are highly effective as a result.

EEI’s for ADA (Americans with Disabilities Act)[edit]

EEI’s can provide the owners and operators of buildings with inexpensive access to the Americans with Disabilities Act compliance through an openly evidenced approach at “best management practices” to provide safety to their tenants in their buildings, properties and communities. This is especially important in properties where the hearing or visually impaired are to known to frequent or reside. A benefit to the design of EEI’s is that they can easily be utilized in outdated or older buildings where the public convenes or many people gather without substantial construction taking place to install them. Providing large assemblies of gathered people with an enhanced exit discharge location identification at little expense to the building operator can be important for the people gathered there and the building operator himself. When installed, EEI’s provide a much more identifiable discharge location to evacuees of that building when it is experiencing a crisis like fire. Some makers of the EEI are currently working with the International Code Council (ICC) and the National Fire Protection Association (NFPA) to bring this technology to Authorities Having Jurisdiction (I.e. AHJ's) through code which will allow them to require the use of EEIs in settings where they deem appropriate (such as assisted living facilities and licensed care facilities, day care centers, higher occupancy residential properties where these devices can make a difference to the building's occupants in fire crisis.

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