Presented by. NKBA and. Benya Lighting. James Robert Benya, PE, FIES,. IALD, LC. BENYA LIGHTING DESIGN. Portland, OR. Lighting Design Basics. The Basics of Light and Designing Lighting Systems. • Lighting Roadways. • Example Project. • More on LEDs. • Discussion and Questions. The influence of stage lighting Qualitative lighting design Lighting engineering and lighting design Basics. Perception.
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Lighting design basics / by Mark Karlen and James Benya. p. cm. Includes index. ISBN (Paper) 1. Lighting. 2. Lighting, Architectural and. Providing the fundamental information new designers need to succeed in a concise, highly visual format, the Second Edition of Lighting Design Basics presents. Emergency lighting. Chapter 5. Lamps. Chapter 8. Technology and tables. Chapter 9. Design tools. Chapter 6. Lighting control and control gear. Chapter 1.
Here are the most common control devices and how to use them. Switches Switches turn lights on and off. Most switches are levers and mechanical devices that open and close electrical contacts in the power circuit directly feeding the lights.
The two most common switches types are toggle and decora paddle. Some switches feature a finder light the switch is illuminated in the dark or a pilot light the switch is illuminated when the lights are turned on.
A switch should be located next to the door as you enter a room, preferably on the latch side, and mounted 42" above the floor in order to conform with ADA requirements. Switches must be located at each entry of a room. Multiple switch locations require switches called three-way and four-way that permit any switch location to turn the lights on and off.
Use one switch for each group of lights to be controlled together. For example, in office buildings, place luminaires near windows on separate switches from those further into the building.
This permits energy savings by allowing the occupant to turn off lights near windows during the day. For incandescent lights, dimmers or dimmer switches are usually used in place of regular switches, either wall-mounted or on the luminaire itself. For fluorescent lights, the fluorescent ballast must be a dimming type connected to a compatible dimmer switch. Dimmers almost always combine the dimming electronics with a switch, so they are really switch-dimmers.
How the switch part works is just as important as the dimmer part. In a single-action dimmer, the lights must be dimmed completely before the switch action occurs. In a preset dimmer, the switch and the dimmer require separate actions.
Preset dimmers are generally better because they allow three-way and four-way switching, and they permit setting a preferred light level and leaving it there even when lights are switched. Among the several styles of dimmer, the most common are the rotary dimmer and the slide dimmer.
In the rotary dimmer style, the preset dimmer often has a push-on, push-off dial. In the slide dimmer style, the preset dimmer may have a rocker switch, a push-on, push-off switch, or a touch switch with a separate dimmer slide. Lighting designers, in addition to considering dimmer style differences, must also select dimmers according to their load, called the dimmer rating.
Here are the most common dimmer ratings. The minimum rating is watts; dimmers can be rated up to watts. Such dimmers are rated for magnetic transformers or electronic transformers. These dimmers can also dim regular incandescent lamps and mixed loads of incandescent lamps and low-voltage lighting. They are usually rated in volt-amps VA , which are roughly the same as watts. Magnetic-rated dimmers are rated at least VA; and electronic rated dimmers are rated at least VA. To dim fluorescent lighting, the lamps must have dimming ballasts.
In addition, the dimmer must be designed to operate with the specific dimming ballast being used. Motion sensors save energy and add convenience. The most common motion sensors are wall-switch types, designed to replace ordinary manual switches. Several types are available, including one that is both a motion sensor and dimmer. Unfortunately, wall motion sensors are not always located in the best spot to detect motion; the better approach is to place a sensor close to the smallest regular motions that must be detected.
Motion sensors are also made to be mounted on the ceiling, on the upper walls, in corners, or on workstation shelves. These types of sensors usually operate a relay located above the ceiling. One type, designed for connection to a specific type of plug strip, can control task lights and office equipment like computer monitors and printers. Time Clocks A time clock is an electromechanical clock that opens and closes a circuit at specific times each day.
Some models of time clock have stored energy to maintain timekeeping during power outages; others have astronomic time dials to automatically compensate for the changing sunrise and sunset times of the year.
Modern versions of time clocks replace the timekeeping mechanism with a programmable electronic clock. Timers A timer is a switch that turns lights off automatically after a certain period.
Historically, timers used a wind-up mechanical dial. One of the most common applications is switching heat lamps in bathrooms. Modern timers use a pushbutton start and a programmable timeout period. Photoswitches For basic dusk-to-dawn lighting controls, it is possible to use a simple photoswitch in which a photocell throws a switch when the ambient light levels are sufficiently low.
Photoswitches are most common in streetlights and parking lot lights, but they can also be used to switch indoor lights, especially in daylighted spaces like malls and lobbies. Systems enable building operators to control lights better. In some very large and complex facilities, like stadiums and arenas, lighting controls are essential.
Relay Systems A low-voltage control system can be used to remotely control lighting through relays. Relays are devices that control lighting power by mechanically opening or closing according to signals sent from low-voltage rocker switches, time clocks, or computer-based energy management systems. Relay systems are typically used in large commercial and institutional buildings like high-rise offices, convention centers, and airports.
In a relay control system, each group of lights that are switched together must be connected to the same relay. Many relays are located together in a panel, usually next to the circuit breaker panel.
Relay systems are best for large facilities with big rooms that do not require dimming, such as schools, laboratories, factories, and convention centers.
Energy Management Systems Energy management systems employ a computer to control many relay panels as well as mechanical motors, dampers, and so on. The primary difference between a relay system above and an energy management system is that the latter controls not just lighting but all energy use in the building. Chapter 5. Chapter 6. Lighting Calculations.
Documenting Lighting Design. Chapter 8. Lighting Concepts: The Layers Approach. Chapter 9. A Basic Approach to Lighting Design. Chapter Residential Lighting Design.
Office and Corporate Lighting Design. Hospitality Lighting Design. Understanding the fundamental difference between natural and man-made light is the beginning of understanding light sources. Natural light sources occur within nature and are beyond the control of people. These include sunlight, moonlight, starlight, various plant and animal sources, radioluminescence, and, of course, fire.
Man-made light sources can be controlled by people, more or less when and in the amount wanted. These include wood flame, oil flame, gas flame, electric lamps, photochemical reactions, and various reactions, such as explosives. Due to their obvious advantages in terms of availability, safety, cleanliness, and remote energy generation, electric lamps have displaced almost all other man-made sources for lighting of the built environment.
However, because man-made sources consume natural resources, natural light sources should be used to the greatest extent possible. Exploiting natural light sources remains one of the biggest challenges to architects and designers. These qualities are critical to the result and must be understood when choosing the source for a lighting plan. How Light Is Generated Most natural light comes from the sun, including moonlight. Its origin makes it completely clean, and it consumes no natural resources.
But man-made sources generally require consumption of resources, such as fossil fuels, to convert stored energy into light energy. Electric lighting is superior to flame sources because the combustion of wood, gas, and oil produces pollution within the space being illuminated.
Moreover, electricity can be generated from natural, nondepletable sources of energy, including the energy generated by wind, hydro, geothermal, and solar sources. We tend to organize color into three primaries red, green, and blue and three secondaries yellow, cyan, and magenta. When primaries of light are combined, the human eye sees white light Historically, using a filter to remove colors from white light generated colored light. Blue light, for instance, is white light with green, and red removed.
Filtered light is still common in theatrical and architectural lighting. However, most nonincandescent light sources tend to create specific colors of light. Modern fluorescent lamps, for example, create prime colors of light red, green, and blue that appear to the human eye as white light.
Other lamps, such as low-pressure sodium lamps, create monochromatic yellow light. While most lamps are intended to appear as white as possible, in some cases lamps are designed to create specific colors, such as green or blue. However, the intent of most light sources is to produce white light, of whose appearance there are two measures: Edison Lamp How an electric lamp operates determines virtually everything about the light created by it.
The common incandescent lamp generates light through the principle of incandescence, in which a metal is heated until it glows. Most other lamps, however, generate light by means of a complex chemical system in which electric energy is turned into light energy where heat is a side effect. These processes are usually much more efficient than incandescence — at the cost of complexity and other limitations. Color temperature, which describes whether the light appears warm reddish , neutral, or cool bluish.
The term temperature relates to the light emitted from a metal object heated to the point of incandescence. Color rendering index CRI , which describes the quality of the light on a scale of 0 horrible to perfect. All white light sources can be evaluated by color temperature and CRI.
Color temperature is the more obvious measure; two light sources of the same color temperature but different CRI appear much more alike than do two light sources of similar CRI but different color temperature. Natural light is generally defined as having a CRI of perfect.
Color temperature, however, varies a great deal due to weather, season, air pollution, and viewing angle. For instance, the combination of sun and blue skylight on a summer day at noon is about K, but if the sun is shielded, the color of the blue skylight is over 10,K.
The rising and setting sunlight in clear weather can be as low as K very reddish. Cloudy day skylight is around K. When choosing electric light sources, it is generally best to select source color temperature and CRI according to the following table. Note that even if daylight enters the space, it is usually not a good idea to try to match daylight with electric light, as daylight varies considerably.
General residential lighting. Hotels, fine dining and family restaurants, theme parks. Voltage The electric power needed to operate a lamp is measured first by voltage. In the United States, the standard voltage services are volts, volts, volts, and volts. The standard volt service is available in all building types; , , and volt services are available only in large industrial and commercial buildings.
Service voltage varies from country to country. Many types of low-voltage lamps, operating at 6, 12, or 24 volts, are used throughout the world. Transformers are used to alter the service voltage to match the lamp voltage. Bulb Temperature The bulb of a lamp can get quite hot. The bulb temperature of incandescent and halogen lamps and most high-intensity discharge HID lamps is sufficiently high to cause burns and, in the case of halogen lamps, extremely severe burns and fires.
Fluorescent lamps, while warm, are generally not too hot to touch when operating, although contact is not advised. The three basic shape types are point sources, line sources, and area sources. Each radiates light differently, thus causing distinctive effects. Fluorescent lamps are sensitive to temperature caused by the ambient air. If the bulb of the lamp is too cool or too hot, the lamp will give off less light than when operated at its design temperature.
Most other lamps give off the same amount of light at the temperatures encountered in normal applications. Operating Position Ballast or Transformer In order to operate correctly, many electric light sources require an auxiliary electric device, such as a transformer or ballast. This device is often physically large and unattractive and can create an audible hum or buzz when operating.
Some lamps produce more light or have longer lamp life when operated in specific positions with respect to gravity. Metal halide lamps are especially sensitive; some versions will not operate unless in the specified position. Starting, Warming Up, and Restarting Lamp Size The physical size of the lamp affects the size of the luminaire and, in turn, determines how some sources might be used.
Small, low-wattage lamps permit Some lamps, especially incandescent, start operating as soon as power is applied, but most other types, especially discharge lamps, like fluorescent and metal halide lamps, require the lamp to be started by a high-energy pulse.
If then extinguished, fluorescent lamps can be restarted right away, but most HID lamps, like metal halide lamps, must cool considerably before restarting, potentially causing several minutes of unwanted darkness.
Obviously, these considerations can dramatically affect design when safety or security might be compromised by a long warm-up or restart time. Dimming Characteristics Dimming is the process by which lamps are operated at less than full light, often as an energy-saving or mood-creating method. With incandescent lamps, dimming is simple and inexpensive, but with other types, dimming can be considerably more complex, and, in some cases, not advisable.
Energy Efficiency The energy efficiency of a light source is called its efficacy and is measured in lumens per watt. Like miles per gallon, the higher the number, the better. Low-efficacy lamps, like incandescent lamps, are less than 20 lumens per watt. Among good colored light sources, metal halide and fluorescent lamps can achieve up to about lumens per watt; distorted color sources, like lowpressure sodium lamps, presently achieve almost lumens per watt.
The hotter the filament, the whiter the light. The problem is that as the lamp filament gets hotter, the more rapid the evaporation of metal from the filament. A very dim lamp giving off yellow-orange light K may last a long time; a lamp giving off pure white K light will probably last for a few seconds only. The evaporated filament material blackens the bulb wall.
Standard incandescent lamps today use tungsten filaments that generate a warm-colored white light and last about to hours. Two special types of incandescent lamps — krypton-incandescent lamps and xenon-incandescent lamps — make lamps last a bit longer. The color temperature of incandescent lamps is about K, generating a warm-toned light.
Incandescent Lamps Tungsten-halogen lamps also called TH or simply halogen lamps give off whiter light and last longer than standard incandescent lamps. Lamp life for halogen lamps ranges from hours up to 10, hours. Some types of halogen lamps use a quartz glass bulb and get extremely hot, requiring special protection for safety. The color temperature of halogen lamps is about K, making their light appear slightly whiter and cooler than incandescent.
Low-voltage incandescent and tungsten-halogen lamps are smaller than regular lamps, a trait that has numerous advantages for accenting and display. Lowvoltage lighting is particularly popular for specialty lights and for display lighting in retail, museums, homes, and other applications. For instance, most popular do-it-yourself landscape lighting is low-voltage.
Transformers are needed to change the primary power, usually volts, to the low voltage.
The most common systems are 12 volts; these are used to power the popular MR16 and PAR36 display lamps. Some transformers are part of the luminaire, while in other applications a remote transformer can power a lighting system consisting of many lamps.
However, their inefficiency and short life are critical drawbacks that must be resolved in the design. Most Common Applications Standard incandescent lamps, such as A and R lamps, are still commonly used in residences, hotels and motels, and some retail environments where a residential-like quality is desired.
In these applications, the designer is trading the low energy efficiency and short life of the incandescent lamp for its warm color and low costs. Halogen PAR lamps are commonly used in residential downlighting and outdoor lighting, hotels and motels, and especially in retail display. MR16 and PAR Parabolic Aluminized Reflector Lamp low-voltage lamps are commonly used in museums and galleries, residences, landscape lighting, and other applications where a modest amount of light and excellent beam control are called for.
Other types of low-voltage lighting are used in residential and hospitality lighting for details and special effects like cove lights and illumination inside and under cabinets. They start and warm up almost instantly and can be extinguished and restarted at will. Incandescent and halogen lamps can be dimmed easily and inexpensively. Dimming generally extends lamp life significantly. Incandescent lamps are among the least energy-efficient sources available. Standard incandescent lamps generate between 5 and 20 lumens per watt; halogen lamps generate between 15 and 25 lumens per watt.
The most efficient incandescent light sources are the latest infrared-reflecting halogen lamps, which generate between 20 and 35 lumens per watt. Designers tend to prefer incandescent and halogen lamps for their color and versatility.
When dimming, incandescent lamps are the only type that shifts color toward red as intensity decreases. Fluorescent lamps use the principle of fluorescence, in which minerals exposed to ultraviolet light are caused to glow. Electric energy excites the gas inside the lamp, which generates ultraviolet light. The ultraviolet light in turn excites the phosphors, which are a mixture of minerals painted onto the inside of the bulb. Phosphors are designed to radiate particular colors of white light, thus enabling the choice of both the color temperature and CRI of a lamp.
The color of the lamp is described by the name or designation. Traditional lamp colors include cool white, warm white, and daylight. For example, a lamp having a color temperature of K and a CRI between 80 and 90 is known as the color A ballast is an electrical component that starts the lamp and regulates the electric power flow to the lamp. Some ballasts can operate up to four lamps. There are two types, magnetic and electronic, of which the latter is generally more energyefficient and quieter, and it reduces lamp flicker considerably.
Fluorescent lamps can be dimmed through the use of an electronic dimming ballast. Most electronic dimming ballasts require specific dimmers. Dimming range is typically 10 to percent of light or better, with the best ballasts allowing a dimming range of 0. Fluorescent lamps change color slightly when dimmed; their light tends to appear more purple at lower output levels. Fluorescent lamps are sensitive to temperature.
Bulb temperature is critical for proper light output, and lamps operated in very cold or very warm situations generally do not give off as much light as when operated at room temperature. Also, lamps may not start if they are too cold. The minimum starting temperature of a lamp depends on the ballast; minimum starting temperature ratings are available for ballasts to help choose the right type. Most fluorescent lamps get warm, but a person can touch one in operation without being burned.
The longest standard fluorescent lamps are 8' long and the shortest are 4". U-bent lamps are straight lamps that are manufactured in a U shape but otherwise perform about the same as straight lamps.
Standard straight and U-bent lamps are preferred for general illumination because of their cost effectiveness and energy efficiency. In current designs, the T-8 is the most commonly used general-purpose lamp, and the T-5 and T5 high-output lamps are becoming increasing popular for a number of specific lighting systems.
The T lamps are an older style that is less energy efficient. Compact Fluorescent Lamps There are two major types of compact fluorescent lamps: As a result, it is generally best to employ dedicated compact fluorescent luminaires in new designs. Screw-based compact fluorescent lamps should be used to convert incandescent type luminaires only after the fact. The cool-off period is called the restrike time.
Some HID lamps must cool more than 10 minutes after being extinguished before they can restrike and warm back up. Points to Remember About Fluorescent Lamps Types of HID Lamps Fluorescent and compact fluorescent lamps provide good energy efficiency, good to excellent color, dimming, and many other features expected of modern light sources. Improvements in fluorescent lighting since now make it useful in homes, businesses, and for almost every other type of lighting application.
Fluorescent and compact fluorescent lamps can be used in many places, however, and it is important to develop expertise in using these energy-efficient sources. Metal Halide Lamps Metal halide lamps produce white light of a good color quality and are available in many sizes, from compact lamps that can be used in track lighting and table lamps to huge lamps for lighting stadiums. They are most often used for street and parking lot lighting and for large indoor spaces like gymnasiums and industrial work floors.
Most HID lamps approximate a point source of light, making them excellent sources for spot lighting equipment such as track lights, display lights, and even stadium lights. HID lamps are generally energy efficient, producing 50 to lumens per watt. As in fluorescent lamps, a ballast regulates the amount of power flowing into HID lamps. Magnetic ballasts are generally used for most HID lamps, although electronic ballasts are becoming increasingly popular.
Ballasts can be bulky, heavy, and noisy, but some types can be mounted remotely from the luminaire. HID lamps can get quite hot and generally should be protected from direct touch. In addition, some metal halide lamps must be totally enclosed due to a small possibility of lamp explosion. HID lamps start and operate over a relatively wide temperature range, and they are well suited to both indoor and outdoor applications.
HID lamps require time to warm up; they get progressively brighter over several minutes until reaching full light output. Their CRI is 65 to Standard metal halide lamps typically are used where color is not critical, such as sports arenas, parking lots, landscape lighting, and building floodlighting. The latest metal halide lamps are called ceramic metal halide lamps.
They exhibit superior color rendering 80 to 85 and a choice of warm K or cool K lamps. They can be used for interior lighting, such as downlighting, display lighting, and wallwashing, as well as for exterior lighting.
Sodium lamps tend to be yellowish in color. HPS lamps exhibit a golden-pinkish light that tends to create spaces with a distinctly brown or dirty quality. Low-pressure sodium emits monochromatic yellow light, creating stark scenes devoid of color altogether. Although HPS lamps offer very high lumens per watt, their color deficiencies limit use to lighting roads, parking lots, heavy industrial workspaces, warehousing, security lighting, and other applications where light color is not important.
LPS lamps are even higher in lumens per watt, but their color is so poor that their use is limited to security lighting. Mercury Vapor Lamps Mercury vapor lamps are an older type of lamp that remains in common use as streetlights and security lights. However, compared to other HID lamps, mercury vapor lamps have relatively poor color and low energy efficiency.
They are almost never used in new construction. Induction lamps have most of the characteristics of fluorescent lamps, including 70 to 80 lumens per watt, choice of color, and high CRI. However, because induction lamps have no electrodes, the lamps are rated to 60, to , hours. An induction lamp used every day for 12 hours will last more than 20 years.
Typical applications include streetlighting and lighting in hard-to-maintain locations. This is expected to change as technological growth in this source progresses.
However, LED lamps can be used in specialty applications, including signs and display lighting. Systems employing red, green, and blue LED lamps can be used to create changing color washes.
At present, the most common architectural application of LED lamps is in exit signs. Automotive and sign lighting applications, including traffic signals, are multiplying rapidly. While their primary applications are signs and specialty lighting, both neon and cold cathode lamps can be used for architectural lighting applications. Both types last 20, to 40, hours, are reasonably energy efficient, and can be dimmed and even flashed on and off without affecting lamp life.
When thinking of neon and cold cathode lamps, imagine tubular lighting that can be formed into just about any shape and be made to create just about any color of light. Cold cathode lighting is like neon, but generally the lamps are larger in diameter and the light source is used for architectural rather than sign lighting. Cold cathode lamps are also distinguished by having a plug-in base, where neon tubing usually terminates in base wire connectors.
In architecture, neon lighting is most often used for special effects, such as cove lighting, building outlining, and color accents, especially in casinos and retail lighting. Cold cathode lamps produce more light than neon; they are typically used for cove lighting and outlining in conventional building types, such as hotels, convention centers, and office buildings. Lighting fixtures are luminaires that are permanently attached to a building. In other words, a table lamp is a luminaire but not a fixture.
Luminaires are characterized by the manner in which light is distributed: These include most types of recessed lighting, including downlights and troffers. These include many styles of suspended luminaires, sconces, and some portable lamps. These include most types of bare lamps, globes, chandeliers, and some table and floor lamps.
These include many types of suspended luminaires as well as some table and floor lamps. Asymmetric uplights, for instance, are indirect luminaires with a stronger distribution in one direction, such as away from a wall.
Wallwashers are a form of direct luminaire with stronger distribution to one side so as to illuminate a wall. These include track lights, floodlights, and accent lights. Here are reasons for choosing particular luminaires: They generally create dark ceilings and upper walls that can be dramatic but also uncomfortable due to high contrast.
Direct lighting is typically used in building lobbies, executive offices, restaurants, and other spaces where the designer wishes to convey a sense of drama. Dramatic spaces can be tiring, though, so direct lighting is generally not recommended for workspaces. Most types of indirect lighting illuminate the ceiling, but without additional direct light, many people experience totally indirect lighting as bland and feeling like a cloudy day.
Indirect lighting is generally preferred for spaces in which people spend a lot of time working, although some task light or other directional light is generally recommended to eliminate the bland character.
Most chandeliers and sconces are diffuse luminaires, and they are typically chosen for ornamental reasons or for utilitarian applications. When used carefully, as in a crystal chandelier, diffuse luminaires can create sparkle and interest, but other lighting must also be present.
Without other light, diffuse luminaires tend to create a flat, uninteresting light that is often uncomfortable. The indirect component creates a comfortable, balancing light, while the direct component creates a dramatic light, resulting in comfortable, interesting space. For example, choose a wallwasher to illuminate a wall, an accent light to illuminate a painting or sculpture. A type of direct luminaire, they are usually round and recessed in the ceiling.
Their principal use is general illumination in a wide range of residential and commercial applications, especially in lobbies, halls, corridors, stores, and other finished spaces. Downlights can be equipped with incandescent, halogen, low-voltage incandescent, compact fluorescent, or HID lamps. Downlights typically consist of two parts: The can must be suitable for the application. Here are the primary rating types: IC cans are typically used in homes, especially in ceilings with attics above.
A special type called an airtight IC can is required in Washington State for energy efficiency. Damp location luminaires can be exposed to moist air but not to direct water spray or rain.
Most cans are damp rated. Wet location fixtures can be exposed to direct water spray or rain, including extreme conditions outdoors. Spa or shower fixtures are designed for use in shower stalls and over spas.
Emergency fixtures are equipped with a backup battery so as to produce light for at least 90 minutes during a power outage generally, only compact fluorescent luminaires are so equipped. Most downlights allow for trims that fit into the can. Among the many choices are open baffles, open reflectors, wallwashers, adjustable accents, and various lens trims. Trim choice can dramatically affect the light quality generated by the downlight. Troffers Troffers are widely used in offices, stores, schools, and other commercial and institutional facilities for general lighting in work and sales areas.
Troffers are the most common type of fluorescent luminaire. The lens serves to cut off light distribution to minimize glare. The lens can also protect lamps from breaking in food preparation and service areas. Lenses can contain internal RFI shields for use in hospital operating rooms and laboratories.
Lens troffers can be equipped with highly polished internal reflectors to obtain very high efficiency. Sharp cutoff is obtained, enabling some parabolics to be used in computer workspaces.
Parabolic generally refers to a deep cell louver 6" or larger across and paracube to shallower smaller cells. Larger cells are more efficient; smaller cells hide lamps better. Like other troffers, these are actually direct luminaires.
Most troffers are recessed and are designed to be laid into acoustic tile ceilings, the fixture face matching the size of the tile. Most troffers are designed to lay in to acoustic tile ceilings. Troffers can be equipped with most fluorescent technologies, including dimming, magnetic or electronic ballasts, and T or T-8 lamps. They can be equipped with emergency battery packs to power some or all of the lamps during a power outage or emergency condition.
The most common type is the wraparound, wherein a lens or diffuser top surrounds the lamps, hiding them from direct view while radiating light downward and to the sides. Commercial luminaires are among the lowest-cost lighting fixtures. They are typically used for general and utility lighting in modest projects. The majority of commercial fixtures are rated for dry locations. They use T12 or T-8 lamps. Some have damp labels, and most can be equipped with a battery pack for emergency power.
Fluorescent industrials are strip lights and open fixtures with simple reflectors designed to be surface-mounted or hung by chains or rods. HID industrials include high-bay downlights and low-bay downlights. Industrial fixtures are generally used in factories, warehouses, and, increasingly, in schools and retail stores where a less finished appearance is desired. Although most industrials are direct lighting, many are semi-direct — that is, having a small percentage of uplight to improve visual comfort.
Most industrial fixtures are listed for dry locations. Some are finished in glass or porcelain to resist corrosion caused by airborne gases or particles. Others utilize aluminum or plastic construction. Certain fixtures are specifically designed for demanding environmental applications ranging from wet and saltwater marine luminaires to explosion-proof products for use in petrochemical plants, grain storage facilities, and other hazardous locations.
Linear Lighting System Industrial Fluorescent Fixture Linear Lighting Systems Linear lighting systems are fluorescent luminaires having indirect, semi-indirect, and direct-indirect lighting distribution; they are designed to illuminate offices and other more finished spaces. Because the luminaires can be obtained in varying lengths and assembled into patterns, they are called linear systems.
Indirect lighting systems produce uplight only. Generally, they are mounted at least 15" to 18" below the ceiling; longer suspension lengths improve unifor- mity of light on the ceiling. To maintain adequate clearance, it is usually necessary for ceilings to be at least 9' high. Semi-indirect systems having a small percentage of downlight should be used in the same manner. Direct-indirect lighting systems are intended to produce both indirect lighting, for its comfort and balance, and direct light, for task lighting.
Suspension length and ceiling height are not as fixed as for indirect lighting. The ratio of uplight to downlight varies; generally, the higher the ceiling, the greater the downlight percentage should be. Almost all luminaires of this type are for dry and relatively clean indoor locations.
They usually use T-8, T, or T-5 lamps and often are equipped with battery packs for emergency lighting. Some versions permit track or low-voltage accent lighting on the bottom of the luminaire together with fluorescent uplight.
Architectural Lighting Fixtures Architectural lighting fixtures are fixtures that are not decorative but rather functional and inconspicuous. They are used to illuminate architectural shapes and forms. Accent fixtures allow light to focus on art and building surfaces. Cove Lights Wall Grazing Fixtures Wall grazing fixtures, sometimes called wall slots, are used to illuminate walls in lobbies, corridors, and core areas. They are especially well suited to textured and polished surfaces.
Cove lights permit uplighting from coves or other architectural elements more efficiently than do strip lights, and without socket shadows. Task Lights Task lights are specially designed to illuminate a desk area while minimizing veiling reflections. Chandeliers are hung from the ceiling and are used for general illumination in dining rooms, foyers, and other formal spaces.
In general, the term pendant is used for hanging luminaires less formal than chandeliers that are used in offices, restaurants, and many other places.
Most pendant luminaires use incandescent lamps, although modern variations are also available with HID and fluorescent sources. Often, sconces match an adjacent chandelier; at other times, they are the sole decorative lighting element. Sconces exhibit a wide range of style, from crystal fixtures with flame-tip lamps to modern designs. Most use incandescent or halogen sources, although compact fluorescent options should be considered for commercial and hospitality applications.
Close to Ceiling Chandelier Most decorative luminaires can be used in dry indoor spaces only. A few types, notably lanterns and some sconces, are wet-labeled, meaning they can be exposed to direct rain. Unless project requirements call for unique or specialized lighting, it is often best to design using common luminaire types.
Here are some of them: In general, the luminaires should be specified with two T-8 lamps, electronic ballast, and a prismatic acrylic lens.
Wraparound luminaires are suited for low-ceiling applications; in general, they should not be used above 10'. These tend to have a utilitarian appearance and are unsuitable for computer workspaces. This is the least expensive lighting system for use in suspended ceilings for a wide variety of projects. In general, these luminaires should be specified with two or three T-8 lamps and an electronic ballast.
They tend to have a low-budget appearance. They are not recommended for use in computer workspaces. Wraparound Fluorescent Lens Troffer 2' x 4' Lay-in Troffer with Large-Cell Parabolic Louver This standard lighting system is appropriate for offices, stores, and many other building types with suspended ceilings.
In general, the luminaires should be specified with two or three T-8 lamps and an electronic ballast; the number of rows of cells should equal the number of lamps. They tend to have an upgraded appearance and are at the low end of acceptable lighting quality for computer workspaces. Parabolic Troffer Fluorescent Strip This very low-cost lighting system can be used in a variety of applications, ceiling systems, and architectural details, such as valances.
In general, the luminaires should be specified with T-8 lamps and electronic ballast. Further, they should be specified in single-lamp, two-lamp, two-lamp end-to-end tandem , and four-lamp tandem luminaires using 4' or 8' lamps.
The luminaires should be specified in two-lamp or four-lamp tandem luminaires using 4' or 8' T-8 lamps and electronic ballast. They are available as solid reflectors and reflectors with uplight slots. This moderate-cost lighting system looks like a metal halide industrial downlight, but it employs multiple compact fluorescent lamps.
It can be used at mounting heights up to 30'. While lower in efficacy than pulse-start HID, multiple compact fluorescent lamps offer superior color, rapid starting and restarting, and the ability to switch in groups to achieve lower lighting levels for daylighting or varying uses.
This type of lighting must be suspended at least 18" below the ceiling, which necessitates a ceiling height of 9' or more. These systems are applicable as general lighting for offices, classrooms, and some medical spaces, and as ambient light in offices, retail stores, and other locations.
They are considered good lighting for computer workspaces. Low-cost versions are made of sheet steel, while more expensive and styled versions are made from extruded aluminum. Various combinations of lamps are available; the most common selections are two or three T-8 or T-5 lamps or one T-5HO lamp across. The elements are installed in continuous rows approximately 10' to 12' apart and laid out in 4' increments. HID Industrial Downlight This low- to moderate-cost lighting system type is used for industrial medium and high bay spaces generally over 20' mounting height as well as gyms, big box stores, and other spaces with an open, industrial character.
The luminaires should be specified with metal halide pulse start lamps regardless of wattage. This type of lighting must be suspended at least 12" below the ceiling, necessitating a ceiling height of 9' or more. They are considered good lighting for computer workspace.
Moderate-cost versions are made of sheet steel or plastic, while more expensive and styled versions are made from extruded aluminum. The most advanced luminaires use wave guide lens technology. The systems are installed in continuous rows approximately 10' to 12' apart and laid out in 4' increments. Apertures range from 4" to over 10", and the dozens of types include open reflector, open baffle, adjustable, lensed, and decorative ring styles. While the downlight was developed for incandescent lighting, energy-efficient variations include single and multiple compact fluorescent lamps and HID lamps.
Adjustable Downlights A variation of the downlight using PAR lamps and low-voltage lamps, adjustable downlights are important for display lighting. Suspended Direct-Indirect Lighting Recessed Indirect Troffers A relative and attractive newcomer, recessed indirect troffers are slightly more expensive than parabolics but offer a fresh, contemporary appearance for stores, offices, and other sites. They are not a good luminaire for open office areas and other large workrooms, however, so apply them with some caution for their glare potential.
The 2' x 4' version uses two or three 4' lamps. Adjustable Downlight Track and Canopy Monopoints Suspended Indirect Troffer These display lights, which come in many styles, are suitable for illuminating single objects.
The appearance of the luminaire can play an important role. Similar to cans, monopoint variations employ compact fluorescent lamps, MR16 low-voltage lamps, PAR halogen lamps, and low-wattage metal halide lamps. They are typically used with ceilings or soffits up to 12' and wash an area of wall about 3' to 4' wide. Lamp choices include high-wattage tungsten halogen lamps watts , T-5 twin tube fluorescent lamps, and metal halide lamps. Wallwashing is one of the most energy-intensive techniques, so limit the number of washed surfaces to those that really need it.
Wall Sconces Wall sconces are a decorative lighting source that can be equipped with incandescent or compact fluorescent lighting to provide an attractive and effective light. They can be used in hotels and motels, office corridors and lobbies, and a wide variety of other space types. Ceiling drums are round or square luminaires that mount to the ceiling surface. They typically are used as corridor lights, rest room lights, closet lights, and in many locations where a modest amount of light is needed.