Introduction

Over the years, a lot has been written about lighting and return on investment (ROI). We suggest that school administrators contact their electric providers, to conduct an assessment of their lights in and around the school for the purpose of installation of lighting that will give an ROI as well as meeting the proper levels of lighting for cameras and safety issues.

As security consultants we see a variety of hodge-podge lighting in and around schools. We see lights on during the day, broken covers or lenses, a bird’s nest inside a lantern fixture with broken glass, and lens covers that have turned brown from the heat of the bulb. In addition, we see fixtures that are not cost-effective.

Cost and ROI

Cost is broken down into three categories: (1) energy cost (usually 88%), (2) capital cost (8%), and (3) maintenance cost (4%). ROI is broken down into (1) efficiency and energy savings payback, (2) reduce costs by shutting off unnecessary units, and (3) the concept of going green.

From a safety perspective, lighting can be justified because it improves and promotes safety and prevents lawsuits, improves employee morale and productivity, and enhances the value of real estate. From a security perspective, two major purposes of lighting are to create a psychological deterrent to intrusion and to enable detection. Good lighting is considered such an effective crime control method that the law, in many locales, requires buildings to maintain adequate lighting.

One way to analyze lighting deficiencies is to go to the building at night and study the possible methods of entry and areas where inadequate lighting aids a burglar. Before the visit, contract local police as a precaution against mistaken identity and recruit their assistance in spotting weak points in lighting.

What lighting level aids an intruder? Most people believe that, under conditions of darkness, a criminal can safely commit a crime. But this view may be faulty, in that one generally cannot work in the dark. Three possible levels of light are bright light, darkness, and dim light. Bright light affords an offender plenty of light to work but enables easy observation by others; it deters crime. Without light, in darkness, a burglar finds that he or she cannot see to jimmy a good lock, release a latch, or do whatever work is necessary to gain access. However, dim light provides just enough light to break and enter while hindering observation by authorities.

Although much case law supports lighting as an indicator of efforts to provide a safe environment, security specialists are questioning conventional wisdom about lighting.¹ Because so much nighttime lighting goes unused, should it be reduced or turned off? Does an offender look more suspicious under a light or in the dark with a flashlight? Should greater use be made of motion-activated lighting? How would these approaches affect safety and cost-effectiveness? These questions are ripe for research.

Illumination²

Lumens (of light output) per watt (of power input) is a measure of lamp efficiency. Initial lumens per watt data are based on the light output of lamps when new; however, light output declines with use. Illuminance is the intensity of light falling on a surface, measured in foot-candles (English units) or lux (metric units). The foot-candle (fc) is a measure of how bright the light is when it reaches 1 foot from the source. One lux equals 0.0929 fc. The light provided by direct sunlight on a clear day is about 10,000 fc, an overcast day would yield about 100 fc, and a full moon gives off about 0.01 fc. A sample of outdoor lighting illuminances recommended by the Illuminating Engineering Society of North America are as follows: self-parking area, 1 fc; attendant parking area, 0.20-0.90 fc; covered parking area, 5 fc; active pedestrian entrance, 5 fc; and building surroundings, 1 fc. It generally is recommended that gates and doors, where identification of persons and things takes place, should have at least 2 fc. An office should have a light level of about 50 fc.

Care should be exercised when studying fc. Are they horizontal or vertical? Horizontal illumination may not aid in the visibility of vertical objects such as signs and keyholes. (The preceding fc are horizontal.) The fc vary depending on the distance from the lamp and the angle. If you hold a light meter horizontally, it often gives a different reading that if you hold it vertically. Are the fc initial or maintained?

David G. Aggleton, CPP, stated in an article in Security Technology Executive (March 2011) that “A quick rule of thumb for minimum reflected light is: (A) Detection: 0.5 fc, (B) Recognition: 1.0 fc, (C) Identification: 2.0 fc are required.”

Maintenance and bulb replacement ensure high-quality lighting.

Types of Lamps³

The following lamps are applied outdoors:

• Incandescent. These are commonly found at residences. Passing electrical current through a tungsten wire that becomes white-hot produces light. These lamps produce 10-20 lumens per watt, are the least efficient and most expensive to operate, and have a short lifetime of 9000 hours.

• Halogen and quartz halogen lamps. Incandescent bulbs filled with halogen gas (like sealed-beam auto headlights) provide about 25% better efficiency and life than ordinary incandescent bulbs.

• Fluorescent lamps. Pass electricity through a gas enclosed in a glass tube to produce light, yielding 40-80 lumens per watt. They create twice the light and less than half the heat of an incandescent bulb of equal wattage and cost 5-10 times as much. Fluorescent lamps do not provide high levels of light output. The lifetime is 9000-20,000 hours. They are not used extensively outdoors, except for signs. Fluorescent lamps use one-fifth to one-third as much electricity as incandescent with a comparable lumen rating and last up to 20 times longer. They are cost-effective with yearly saving per bulb of $9.00-25.00.

• Mercury vapor lamps. They also pass electricity through a gas. The yield is 30-60 lumens per watt and the life is about 20,000 hours.

• Metal halide lamps. They are also of the gaseous type. The yield is 80-100 lumens per watt, and the life is about 10,000 hours. They often are used at sports stadiums because they imitate daylight conditions and colors appear natural. Consequently, these lamps complement video surveillance systems, but they are the most expensive light to install and maintain.

• High-pressure sodium lamps. These are gaseous, yield about 100 lumens per watt, have a life of about 20,000 hours, and are energy efficient. These lamps are often applied on streets and parking lots, and through fog are designed to allow the eyes to see more detail at greater distances. They also cause less light pollution then mercury-vapor lamps.

• Low-pressure sodium lamps. They are gaseous, produce 150 lumens per watt, have a life of about 15,000 hours, and are even more efficient than high-pressure sodium. These lamps are expensive to maintain.

• LED (light emitting diodes). These are small lights, such as Christmas bulbs, and spotlights. They use very low energy consumption and are long lasting up to 50,000-80,000 hours. This rapidly growing light source maybe the light of the future. Currently they are used in many applications such as in garages, street lighting, and rear tail-lights in motor vehicles. These lights are considered the bulb of the future.

• Quartz lamps. These lamps emit a very bright light and snap on almost as rapidly as incandescent bulbs. They are frequently used at very high wattage—1500-2000 watts is not uncommon in protective systems—and they are excellent for use along the perimeter barrier and in troublesome areas.

• Electroluminescent lights. These lights are similar to their florescent cousins; however, they do not contain mercury and are more compact.

Each type of lamp has a different color rendition index (CRI), which is the way a lamp’s output affects human perception of color. Incandescent, fluorescent, and halogen lamps provide an excellent color rendition index of 100%. Based on its high CRI and efficiency the preferred outdoor lamp for video surveillance systems is metal halide. Mercury vapor lamps provide good color rendition but are heavy on the blue. Low-pressure sodium lamps, which are used extensively outdoors, provide poor color rendition, making things look yellow. Low-pressure sodium lamps make color unrecognizable and produce a yellow-gray color on objects. People find they produce a strange yellow haze. Claims are made that this lighting conflicts with aesthetic values and affects sleeping habits. In many instances, when people park their vehicles in a parking lot during the day and return to find their vehicle at night, they are often unable to locate it because of poor color rendition from sodium lamps; some even report their vehicles as stolen. Another problem is the inability of witnesses to describe offenders accurately.

Mercury vapor, metal halide, and high-pressure sodium take several minutes to produce full light output. If they are turned off, even more time is required to reach full output because they first have to cool down. This may not be acceptable for certain security applications. Incandescent, halogen, and quartz halogen have the advantage of instant light once the electricity is turned on. Manufacturers can provide information on a host of lamp characteristics including the “strike” and “re-strike” time.

The following sources provide additional information on lighting:

• National Lighting Bureau (http://www.nlb.org): Publications.

• Illuminating Engineering Society of North America (http://www.iesna.org): Technical materials and services; recommended practices and standards; many members are engineers.

• International Association of Lighting Management Companies (http://www.nalmco.org): Seminars, training, and certification programs.

Lighting Equipment

Incandescent or gaseous discharge lamps are used in streetlights. Fresnel lights have a wide flat beam that is directed outward to protect a perimeter and glares in the faces of those approaching. A floodlight “floods” an area with a beam of light, resulting in considerable glare. Floodlights are stationary, although the light beams can be aimed to select positions. The following strategies reinforce good lighting:

1. Locate perimeter lighting to allow illumination of both sides of the barrier.

2. Direct lights down and away from a facility to create glare for an intruder. Make sure the directed lighting does not hinder observation by the patrolling officer.

3. Do not leave dark spaces between lighted areas for burglars to move in. Design lighting to permit overlapping illumination.

4. Protect the lighting system. Locate lighting inside the barrier, install protective covers over lamps, mount lamps on high poles, bury power lines, and protect switch boxes.

5. Photoelectric cells enable light to go on and off automatically in response to natural light. Manual operation is helpful as a backup.

6. Consider motion-activated lighting for external and internal areas.

7. If lighting is required in the vicinity of navigable waters, contact the U.S. Coast Guard.

8. Try not to disturb neighbors by intense lighting.

9. Maintain a supply of portable, emergency lights and auxiliary power in the event of a power failure.

10. Good interior lighting also deters burglars and allows passing patrol officers to view the property.

11. If necessary, join Neighborhood Watch Programs to petition local government to install improved street lights.

Twenty-Five Things You Need to Know About Lighting for Your School⁴

1. Watts: Measures the amount of electrical energy used.

2. Foot-candle: Measure of light on a surface 1 square foot in area on which one unit of light (lumen) is distributed uniformly.

3. Lumen: Unit of light output from a lamp.

4. Lamp: Term that refers to light sources that are called bulbs.

5. Lux: Measurement of illumination.

6. Illuminare: Intensity of light that falls on an object.

7. Brightness: Intensity of the sensation from light as seen by the eye.

8. Foot-lambert: Measure of brightness.

9. Glare: Excessive brightness.

10. Luminaire: Complete lighting unit; consists of one or more lamps joined with other parts that distribute light, protect the lamp, position or direct it, and connect it to a power source.

11. Ballast: Device used with fluorescent and high-intensity discharge lamps to obtain voltage and current to operate the lamps.

12. High-intensity discharge (HID): Term used to identify four types of lamps—mercury vapor, metal halide, and high- and low-pressure sodium.

13. Coefficient of utilization: Ratio of the light delivered from a luminaire to a surface compared to the total light output from a lamp.

14. Contrast: Relationship between the brightness of an object and its immediate background.

15. Diffuser: Device on the bottom or sides of a luminaire to redirect or spread light from a source.

16. Fixture: A luminaire.

17. Lens: Glass or plastic shield that covers the bottom of a luminaire to control the direction and brightness of the light as it comes out of the fixture or luminaire.

18. Louvers: Series of baffles arranged in a geometric pattern. They shield a lamp from direct view to avoid glare.

19. Uniform lighting: refers to a system of lighting that directs the light specifically on the work or job rather than on the surrounding areas.

20. Reflector: Device used to redirect light from a lamp.

21. Task or work lighting: Amount of light that falls on an object of work.

22. Veiling reflection: Reflection of light from an object that obscures the detail to be observed by reducing the contrast between the object and its background.

23. Incandescent lamps: Produce light by passing an electric current through a tungsten filament in a glass bulb. They are the least efficient type of bulb.

24. Fluorescent lamps: Second most common source of light. They draw an electric arc along the length of a tube. The ultraviolet light produced by the arc activates a phosphor coating on the walls of the tube, which causes light.

25. HID lamps: Consist of mercury vapor, metal halide, and high- and low-pressure sodium lamps. The low-pressure sodium is the most efficient, but has a very low CRI of 5.

Energy Management

The efficiency and management of lighting is becoming a high priority in commissioning new buildings and upgrading existing systems. Indeed, the subject of energy management is expected to become one of the most important considerations within the building regulation documents and have a tremendous impact on the way the construction industry looks at energy. It is apparent that serious measures must now be taken to reduce energy use and waste. This will have an impact on security lighting and the way it is applied. Lighting experts show an increasing urge to work alongside electrical contractors and installers to help them increase their business opportunities by identifying the roles and applications in which energy-efficient lighting should be installed. Electrical contractors are becoming better educated in lighting design that is effective and energy efficient.

Lighting design personnel need to:

• Recognize inefficient installations.

• Appreciate the environmental, cost, and associated benefits of energy-efficient lighting schemes.

• Estimate energy cost savings and calculate the payback period.

• Recognize the situations in which expert and specialist knowledge is needed in the design of management systems.

• Think in terms of increasing business trying to preserve the environment.

At certain points in time, it was said that lighting any system brighter was advantageous. However, we are now seeing a trend away from large floodlights illuminating the night sky with a strong white glare, as exterior lighting is becoming much more focused on the minimum lux levels required. We are also seeing a move toward directional beams.

The lighting industry wants to remove itself from a proliferation of public and private external lighting schemes to counter the light pollution problem and become more energy and cost conscious in its makeup. There must be a mechanism to tackle the problem of countless floodlights, up lighters, spotlights, decorative installations, and an array of security lighting forms that are badly installed and specified, create light pollution, and use high energy levels.

Lighting pollution is now at the forefront of debates for two main reasons:

(a) Light pollution spoils the natural effect of the night skies.

(b) The greater the light pollution, the greater is the power consumption.

Unfortunately, a certain degree of light pollution is needed to satisfy safety and security applications. Equally, there is always the desire to have purely decorative lighting installations, so the answer lies in a compromise. Systems must be designed with a degree of thought given to the avoidance of light pollution and energy waste. External lighting must provide minimal light pollution, a safe environment, and an attractive feature. For attractive features, we can see a greater use of fiber optic solutions with color-changing effects and lighting engineered to direct the illumination downward. Bollards or recessed ground luminaries can be set into walkways so there is no spill into the night sky. Intelligently designed schemes can ensure that lighting is reflected only in a downward direction so that pedestrians are better guided and the lighting has a pleasing effect with little overspill.

Therefore, within the lighting industry, there is a need is to raise standards in all aspects associated with light and lighting, in particular when it comes to energy management and light pollution. We need to define and harness the pleasures of lighting but at the same time promote the benefits of well-designed energy-efficient schemes among the public at large. There must also be miniaturization and increased lamp life. Energy management must therefore be a part of security lighting.

Lighting Checklist

1. Is the entire perimeter well lit?

2. Is there a strip of light on both sides of fence?

3. Is the illumination sufficient to detect human movement easily at 100 yards?

4. Are lights checked for operation daily prior to darkness?

5. Is extra lighting available at entry points and points of possible intrusion?

6. Are lighting repairs made promptly?

7. Is the power supply for lights easily accessible (for tampering)?

8. Are lighting circuit drawings available to facilitate quick repairs?

9. Are switches and controls

(a) Protected?

(b) Weatherproof and tamper resistant?

(c) Accessible to security personnel?

(d) Inaccessible from outside the perimeter barrier?

(e) Equipped with centrally located master switch(es)?

10. Is the illumination good for guards on all routes inside the perimeter?

11. Are the materials and equipment in receiving, shipping, and storage areas adequately lighted?

12. Are bodies of water on perimeter adequately lit?

13. Is an auxiliary source of power available for protective lighting?

Protective Lighting Checklist

1. Is protective lighting adequate on perimeter?

2. What type of lighting is it?

3. Is the lighting of open areas within the perimeter adequate?

4. Do shadowed areas exist?

5. Are outside storage areas adequately lighted?

6. Are inside areas adequately lighted?

7. Is the guard protected or exposed by the lighting?

8. Are gates and boundaries adequately lighted?

9. Do lights at the gates illuminate the interior of vehicles?

10. Are critical and vulnerable areas well illuminated?

11. Is protective lighting operated manually or automatically?

12. Do cones of light on the perimeter overlap?

13. Are perimeter lights wired in series?

14. Is the lighting at shipping and receiving docks or piers adequate?

15. Is the lighting in the parking lots adequate?

16. Is an auxiliary power source available with backup standby units?

17. Is the interior of buildings adequately lighted?

18. Are parking lots adequately lighted?

19. Are guards equipped with powerful flashlights?

20. How many more and what type of lights are needed to provide adequate illumination? In what locations?

21. Do security personnel report light outages?

22. How soon are burned-out lights replaced?

23. Are open areas of a campus sufficiently lighted to discourage illegal or criminal acts against pedestrians?

24. Are any areas covered with high-growing shrubs or woods where the light is insufficient?

25. Are the outsides of buildings holding valuable or critical activities or materials lighted?

26. Are interiors of hallways and entrances lighted when buildings are open at night?

27. Are areas surrounding women’s dormitories well lighted? Within a college setting?

28. Are campus parking lots lighted sufficiently to discourage tampering with parked cars or other illegal activities?

29. Are areas where materials of high value are stored well lighted? Safes, libraries, bookstores, food storage areas, and so forth?

30. Lamp life versus efficiency?

31. Lamp CRI?

32. Continuous levels of light at night?

33. Provide specific levels of light for CCTV units? We are in the age of HD cameras and HD television monitors as well as low light cameras, all of which are crime deterrents in some cases.

34. Required light for evening patrols?

35. Complex should have an even and adequate distribution of light?

Lighting Levels for Your School Complex

By definition a foot-candle is a unit of illuminance or light falling into a surface. It stands for the light level on a surface one foot from a standard candle. One foot-candle is equal to one lumen per square foot.

0.50 fc for perimeter of outer area

0.4 fc for perimeter of restricted area

10.0 fc for vehicular entrances

5.0 fc for pedestrian entrance

0.5-2 fc for roadways

0.2 fc for open years

0.20-5 fc for decks on open piers

10-20 fc for interior sensitive structures

Open parking light levels are a minimum of 0.2 fc in low-level activity areas and 2 fc in high-vehicle activity areas. If there is cash collection, the light level is a minimum of 5 fc.

• Loading docks: 15 fc

• Loading docks interior: 15 fc

• Shipping and receiving: 5 fc

• Security gate house: 25-30 fc

• Security gate house interior: 30 fc

• For pedestrians or normal CCTV cameras the minimum level of light for:

• Detection is 0.5 fc

• Recognition is 1 fc

• Identification is 2 fc

• Parking structures: 5 fc

• Parking areas or open spaces: 2 fc

• Loading docks: 0.20-5 fc

• Loading dock parking areas: 15-30 fc

• Piers and docks: 0.20-5 fc

Lighting Systems

A lighting system consists of a number of components, all of which are important to the effectiveness of a lighting application. Below is a list of the major components and their function.

• Lamp (also known as a light bulb). Manufactured light source that includes the filament or an arc tube, its glass casing, and its electrical connectors. Types of lamps include incandescent and mercury vapor, which describe the type of technologies used to create the light.

• Luminary (also known as fixture). Complete lighting unit consisting of the lamp, its holder, and the reflectors and diffusers used to distribute and focus the light.

• Mounting hardware. Examples are a wall bracket or a light pole used to fix the correct height and location of the luminary.

• Electrical power. Operates the lamp, ballasts, and photocells. Some lamp technologies are sensitive to reduced voltage, in particular the HID family of lamps (metal halide, mercury vapor, and high-pressure sodium).

Web Sites

The following organizations provide valuable information about lighting:

National Lighting Bureau: www.nlb.org

Illuminating Engineering Society: www.iesna.org

International Association of Light Management Companies: www.nalmco.org

Appendix Lighting Description