Sustainable exit signs
March 8, 2010
An increased focus on sustainable building practices is resulting in innovations in the areas of building design, modern facility operation and energy consumption. Building owners and facility managers are always looking for ways to improve building efficiency, thereby enhancing sustainability and in some cases, improving building safety.
Today’s photoluminescent exit signs and glow-in- the-dark emergency egress markings are getting another look for their ability to cut down on costs and energy consumption. The 2009 International Building Code for example, requires photoluminescent egress systems in all buildings over 75 feet tall.
Furthermore, a number of states, organizations and major corporations are now mandating adherence to Leadership in Energy and Environmental Design (LEED) guidelines in their building projects. This is of major significance to facilities that install new energy- and cost-saving technologies that also enhance employee safety. Since LEED promotes a building- as-a-whole approach to sustainability, these policies become important for any type of building at any stage of its lifecycle.
Exit signs: current technology
There are several choices of exit signs available today ranging from incandescent, tritium, and LED-lit to photoluminescent. While older tubular style incandescent bulbs were long-used for exit signs, as the need for uninterrupted lighting grew and building codes evolved, alternatives surfaced.
Tritium, or self-luminous, exit signs are lit by the radioactive decay of a hydrogen isotope. The radioactivity of the sign is small and relatively harmless, and these signs are still common.
Due to their low draw on power, electric-powered LED exit signs are a popular technology in today’s building industry. However, because these signs contain batteries and circuit boards, they eventually require maintenance or replacement. And because they are considered electronic equipment, LED signs must be recycled like a computer or any other electronic device that is classified as a hazardous material.
Exit signs are required to stay lit for safety during a power outage. Photoluminescent exit signs do not require an electrical or battery-powered connection as do those that rely on lead calcium and nickel cadmium batteries when a building’s power is disrupted. This makes photoluminescent exit signs the more sustainable and highly reliable choice for any facility.
LEED-ing the way
The LEED program is a system for designing, building, operating and certifying “green” buildings by encouraging designs that significantly reduce or eliminate the negative impact a building might otherwise have on the environment. The impact a whole-building lighting system will have is a critical component of LEED design. Technological advances, including exit signage and egress systems that employ photoluminescence, can play a big role in meeting requirements for these green certifications.
Your building may qualify for LEED credits with the help of photoluminescent exit signage. The LEED Green Building Rating System evaluates a facility’s environmental performance over its projected lifecycle. The rating system is organized into six credit categories that include: Energy and Atmosphere, Sustainable Sites, Water Efficiency, Indoor Environmental Quality, Materials and Resources, and Innovation and Design Process.
Photoluminescent exit signs can contribute to securing points in the following two areas for LEED Credits:
1) EA Credit #1 – Energy and Atmosphere: optimizing energy performance
LEED Guidelines for exit signs are based on the installation of modern LED exit signs. Conservatively calculated, these signs use approximately five watts of power. While not terribly significant in small operations, businesses with larger facilities and many buildings may have hundreds of LED exit signs. In these cases the kilowatt hours add up quickly and power draw becomes more significant.
Since photoluminescent exit signs are charged by ambient lighting, they require no direct power supply. This is an additional factor influencing the LEED calculations that determine energy efficiency. Depending on the number of exit signs in your facility, this energy savings can be applied toward points for EA Credit #1.
2) ID Credit #1.1 – Innovation and Design Process
To achieve points in this category you must demonstrate significant environmental benefits derived from the applied products and their technologies along with exceptional performance. Because photoluminescent exit signs do not require electricity, there is no contribution to greenhouse gases or production of other byproducts of electrical energy use. And because these signs do not require electricity, there is no need to incorporate additional materials such as electrical switches, wires or conduit as would be needed with LED exit signs.
With regard to recycled material, photoluminescent exit signs use a high content of recycled metal, whereas LED or Tritium signs are prohibited from municipal landfills and require a special recycling process as well as a special disposal process. Photoluminescent exit signs also contribute to a longer lifespan for prolonged use without replacement as well as an elimination of maintenance. Stressing the reliable performance of photoluminescent exit signs, their minimal environmental impact and their lifecycle benefits will help earn ID Credit 1.1 points.
A bright future
Considering the LEED focus on buildings as a whole, photoluminescence is especially remarkable given the energy and cost-savings, the ease of installation and the long-lasting reliability. As a low-cost investment, photoluminescent light technology allows you to take advantage of a major opportunity in OSHA-mandated interior safety lighting and marking.
A number of U.S. cities are upgrading their building codes and soon will be requiring photoluminescent emergency lighting systems for stairways and exit pathways. These new codes are forcing architects, facility managers and building owners to find greener products that are also cost-effective.
To be prepared for the future, take advantage of a few new ideas today. With zero energy consumption, zero energy cost and zero maintenance, photoluminescent exit and directional signs add up to one huge benefit for your building.