Exit sign

Exit sign

An exit sign is a device in a public facility (such as a building, aircraft, or boat) denoting the location of the closest emergency exit in case of fire or other emergency. Most relevant codes (fire, building, health, or safety) require exit signs to be permanently lit. Exit signs are designed to be absolutely unmistakable and understandable to anyone. In the event of an emergency, clear and visible signage can save lives by guiding people to safety.

History

The history of exit signs dates back to the early 20th century, when increased public safety measures led to the standardization of emergency egress systems. The tragic Triangle Shirtwaist Factory fire in 1911, which resulted in the deaths of 146 garment workers, was a pivotal event that highlighted the need for improved safety standards, including better exit signage.

Design and Operation

Exit signs come in various designs, but they all serve the same purpose: to indicate the way to safety. The most common colors for exit signs in the United States are red and green. The choice of color depends on the jurisdiction, with red being the most widely used color in North America, while green is the standard in most European and Asian countries.

Illumination

Exit signs must be illuminated by a reliable light source. There are two main types of illumination:

• Internal illumination: The sign is lit from within by lamps or LEDs.
• External illumination: The sign is illuminated by an external light source.

Modern exit signs are increasingly using LED technology due to its low energy consumption and long lifespan.

Power Sources

To ensure exit signs remain illuminated during power outages, they are often connected to an emergency power source. This can be a backup generator or a battery. Some exit signs are self-contained units with built-in batteries, known as photoluminescent signs, which absorb and store light, then glow in the dark.

Regulations

In the United States, the design and installation of exit signs are governed by codes and standards such as the National Fire Protection Association's NFPA 101, Life Safety Code, and the International Building Code (IBC). These regulations specify the minimum requirements for exit signage to ensure they are visible and legible at all times.

Types of Exit Signs

• Standard Exit Signs: These signs simply display the word "EXIT" or the equivalent in the local language.
• Running Man: Popular in Europe and Asia, this sign depicts a figure running towards an open door.
• Accessible Exit Signs: These signs include the International Symbol of Accessibility and indicate exits that are accessible to individuals with disabilities.

Installation and Maintenance

Proper installation and maintenance of exit signs are crucial for their effectiveness. This includes regular testing to ensure they are operational, especially after changes in building layout or occupancy. Maintenance responsibilities typically fall to the building owner or manager.

Conclusion

Exit signs are a critical component of building safety, guiding occupants to safety during emergencies. Compliance with local codes and regular maintenance ensure that these signs fulfill their life-saving purpose.