Schools and research and development (R&D) facilities are multifaceted, multifunction organizations with the need for flexible and adaptable lighting for safety, security and working tasks.
Start with a thorough site survey and analysis of the facility. For retrofit applications, existing lighting, cabling and power requirements must be considered, as well as other physical construction aspects, such as type of material used in the building structure. In new construction, lighting must be planned from the onset, with key meetings between security, facility management, information technology teams and the end-user, who can accurately describe in detail to the contractor what they expect-and need-from lighting parameters established by the project.
The next stop is the local building code body or the authority having jurisdiction (AHJ). New considerations continue to surface in lighting for schools and R&D and similar high-tech facilities and businesses. Energy codes and a need for more efficient lighting are paramount. Daylight harvesting and the ability to vary light functions with occupancy sensors are also at play, as well as the need to provide overall energy management functions in an efficient, controllable package.
Lighting-related codes may come from a variety of standards-making bodies. The American Society of Heating, Refrigerating, and Air-Conditioning Engineers Inc. (ASHRAE) and the Illuminating Engineering Society of North America (IESNA) jointly sponsor ASHRAE/IESNA Standard 90.1, “Energy Standard for Buildings Except Low-Rise Residential Buildings.”
While its focus is the building envelope and mechanical systems, it does include requirements for interior and exterior lighting. In addition, the International Energy Conservation Code Section 805 details some lighting requirements for these types of commercial buildings. (See “Energy Codes,” Electrical Contractor, September 2005.)
Local municipalities may have a direct say in the type of lighting installed, as was the case with a redevelopment plan in Glenview, Ill. The village developed a master plan and established site design criteria to set a consistent standard for lighting in the following areas: retail and commercial, public streets, and neighborhood parks and public spaces. The area includes the co-located William J. Attea Middle School. The plan was part of the redevelopment of the former Glenview Naval Air Station, located in a northwest suburb of Chicago.
“Portions were village-owned and some community-owned and the goal was to create consistency in site design and lighting throughout the 1,100-acre, mixed-use development,” said Amy Ahner, assistant director, Capital Projects and Planning Department. According to Ahner, it is not unusual for a city or town to establish lighting standards in areas where they are trying to meet economic and aesthetic goals. These areas are typically a downtown or at a gateway entrance to a community, Ahner said.
The Village of Glenview worked with Sternberg Lighting, Roselle, Ill., to develop lighting for the exterior grounds of the school and adjacent park and parking lot. Sternberg specified pole lighting with a candy-cane-shaped arm, which holds single or twin fixtures, depending on the location and the application. In all, 19 single and 31 twin fixtures were installed.
In the park area, the lighting specification includes Sternberg Lighting's NightSky optics, which produce maximum cut-off of light to protect the night sky.
Day and night considerations
It is not enough for a facility to have natural light and windows-it needs to be controlled to meet codes and standards, save energy and positively affect the business conducted within that facility. Controls and switching have become more prevalent in lighting design parameters and can be used to effectively take advantage of available natural light and to tailor lighting levels to match the occupant's preferences or the task at hand, said Tom Leonard, director of Marketing and Product Management for Leviton's Lighting Management Systems Division, Portland, Ore.
“Numerous municipalities and states require various forms of control of lighting,” Leonard said. “Energy codes and standards are driving demand for lighting that can be adjusted to the application, automatically.”
Leonard expects this trend to continue, as businesses seek to establish long- and short-term remedies to the ongoing energy crisis, as well as methods to direct lighting appropriately and intuitively, through occupancy sensors and other automatic methods.
For example, Leonard said controls may switch lights off independently when available light is sufficient. Lighting might not be necessary at certain times of the day or may be used in a lesser intensity and adjusted with dimming controls. The ability to dim fluorescent lights and program that function for automatic operation within the parameters of other energy management systems is becoming the norm as facility managers adapt their buildings to meet daylight harvesting requirements and control costs, Leonard added.
Occupancy sensors from Leviton are one way to provide automatic on/off switching of lighting loads for enhanced convenience, security and long-term energy savings. Another higher level alternative is energy-saving electronic dimming ballasts, which are emerging as a standard within the lighting industry.
All fluorescent lamps, no matter their size or shape, need an additional electrical device called a ballast. Lutron, Advance, Philips and OSRAM Sylvania offer a variety of electronic ballasts that deliver various dimming ranges-some as low as 1 percent-and the ability to turn on the lamp at a designed light level.
“Like HVAC or energy management, lighting has become a dynamic system that can respond to its environment,” Leonard said.
In schools and R&D facilities, fluorescent lighting is still the most cost effective and efficient solution. While light-emitting diodes (LEDs) may be the next trend of the future, they are still cost-prohibitive and not as well suited to multitasking.
Task lighting continues to center on the use of the T-8 fluorescent lamp, with “some in-roads in the market being taken by the T-5 lamp,” said Ken Walma, product manager for the Lutron EcoSystem fluorescent lighting control family, Coopersburg, Pa.
The “T” nomenclature is related to the diameter of the lamp. A T-12 is 12/8 or a 11/2-inch diameter lamp. A T-8 is 8/8 or a 1-inch lamp size. Currently, Walma said, the T-8 is more common and cost effective and fits a wide range of applications within the school facility, allowing the user to deploy one lamp size throughout.
The T-5 is a 5/8-inch lamp size, therefore a smaller diameter and smaller fixture, yet it has more light output, which means fewer lamps. However, the cost of the T-5 lamp versus the T-8 lamp currently can be as much as triple, which adds up in a large facility.
The latest enhancement in fluorescent lighting is intelligent, multiple input digital addressable ballasts. Lutron's EcoSystem fluorescent lighting control products provide daylighting, occupant sensing, personal control and building-wide control through the ballast, which connects directly to photocells, infrared receivers, occupancy sensors and wall stations, without interfaces, power packs or controllers.
Walma concurred with Leviton's Leonard on the need for lighting to be controlled as a dynamic part of a building system.
“Facilities have simply exhausted their ideas when it comes to saving energy. They can change out lamps and ballasts, but can only go so far in reducing energy costs. Now, they need to actively control ballasts with automatic dimming and other controls to get more out of daylight and manual control,” Walma said.
Integrating window coverings in daylighting design helps reduce glare and heat from the sunlight while creating an opportunity for electrical contractors to increase the scope of the project. When proper controllable window coverings are integrated with a comprehensive lighting control system, energy savings could reach up to 70 percent (Reinhart, C.F., 2002 “Effect of Interior Design on the Daylight Availability in Open Plan Offices.” National Research Council of Canada, Internal Report NRCC-45374, NRC: Ottawa).
Lighting has become a task-oriented, stand-alone solution in classrooms and R&D situations. Individual workstations are common. Rooms are large, but have specific areas for dedicated tasks and lighting is often custom-designed for those spaces or includes flexibility built in the way of open ceiling floorplans in which new wiring and connections can be dropped in as necessary.
Other trends are emerging. Learning centers are new buzzwords in engineering classrooms and labs, with the advent of networking capabilities. Walls within the room display projected information. White walls, projection screens and now even gas plasma displays are common.
Around the outside of the room, the lighting is controlled separately of general lighting and also integrated with audiovisual communications. Lighting is varied and controllable, adapting to the application at hand. EC
O’MARA is the president of DLO Communications in Park Ridge, Ill., specializing in low-voltage. She can be reached at 847.384.1916 or firstname.lastname@example.org.