FIGURE 3-11. ILLUSTRATION OF THE IMPORTANCE OF A WHITE CEILING
FOR IMPROVING THE VISUAL ENVIRONMENT OF AN INDUSTRIAL
FACILITY (Courtesy of General Electric Company) Luminaire Top Openings. Top openings in luminaires generally minimize dirt collection on the reflector and lamp by allowing an air draft path to move dirt particles upward through the luminaire to the outer air. Therefore, ventilatec types of luminaires have proven their ability to minimize maintenance of iluorescent, high-intensity discharge, and incandescent filament types of luminaires. Gasketed dust-tight luminaires are also effective in preventing dirt collection on reflector and lamp surfaces.
(3) High Humidity or Corrosive Atmosphere and Classified (Hazardous) Location Lighting. The National Fire Protection Association (NFPA) is phasing out the word "Hazardous" for the word "Classified."
Nonclassified Areas. Enclosed gasketed luminaires are used in nonclassified areas where atmospheres contain nonflammable dusts and vapors or excessive Enclosures protect the interior of the luminaire from conditions prevailing in the area.
Severe corrosive conditions necessitate knowledge of the atmospheric content to permit selection of proper material for the luminaire.
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AC 43 - 204 8/14/97
• Classified Areas. Classified locations are areas where atmospheres contain inflammable dusts, vapors, or gases in explosive concentrations.
are grouped by the National Electrical code on the basis of their hazardous characteristics, and all electrical equipment should be approved for use in specific classes and groups. Luminaires are available, specifically designed to operate in these areas, which are noted in Article 500 of the National Electrical Code as Class I, Class II, and Class III locations. Luminaires used in these areas are designated as: explosion-proof, dusttight, dust-proof, and enclosed and gasketed.
Other Factors. In selecting industrial lighting equipment, the following other factors lead to more comfortable Lighting installations:
• Light-colored finishes on the outside of luminaires to reduce luminance ratios between the outside of the luminaire and the inner reflecting surface and light source.
• Higher mounting heights to raise luminaires out of the normal field of view.
• Better shielding of the light source by deeper reflectors, cross baffles, or louvers. This is particularly important with high-wattage incandescent filament or high-intensity discharge sources and the higher output fluorescent lamps.
• Selecting light control material, such as mirrored or nonmirrored aluminum, prismatic configured glass, or plastic that can limit the luminaire luminance in the shielded zone.
k. Supplementary Lighting. Difficult seeing tasks often require a specific amount or quality of lighting which cannot readily be obtained by general lighting methods. Supplementary luminaires are often used to solve such problems by providing higher illuminances for small or restricted areas. Supplementary luminaires are also used to furnish a certain luminance, color, or to permit special aiming or positioning of light sources to produce or avoid highlights or shadows to best portray the details of the task. Figure 3-12 shows examples of placement of supplementary luminaires.
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e Examples of placement of supplementary luminaires: a. Luminaire located to prevent vailing reflections and reflected glare; reflected light does not coincide with angle of view. b. Reflected light coincides with angle of view. c. Low-angle lighting to emphasize surface irregularities. d. Largearea surface source and patter are reflected toward the eye. e. Transillumination from diffuse sourco.
FIGURE 3-12. EXAMPLES OF PLACEMENT OF SUPPLEMENTARY LUMINAIRES
(1) Nature of Visual Task. Before supplementary lighting can be specified, it is necessary to recognize the exact nature of the visual task and to understand its light reflecting or transmitting characteristics. An improvement in the visibility of the task will depend upon one or more of the four fundamental visibility factors: luminance, contrast, size, and time. Theretore, in analyzing a visual task, it may be found that seeing difficulty is caused by insufficient luminance, poor contrast (veiling reflections), small size, or that the task motion is toc fast for existing seeing conditions.
(2) Planning of Supplementary Lighting. The planning of supplementary lighting also entails consideration of the visual comfort of both those workers who benefit directly and those who are in the immediate area. Supplementary equipment should be carefully shielded to prevent glare for the users and their associates. Luminance ratios should be carefully controlled. Ratios between task and immediate surroundings should be limited as recommended in Table 3-5. To attain these limits it is necessary to coordinate the placement of supplementary and general lighting.
Luminaires for Supplementary Lighting. The IES divides supplementary lighting units into five major types according to candlepower distribution and luminance as follows:
• Type S-I-Directional: Includes all concentrating units. Examples are a reflector spot lamp or units employing concentrating reflectors or lenses. Also included in the group are concentrating longitudinal units, such as a wellshielded fluorescent lamp in a concentrating re- Chap 3 Par 301 Page 81
• Type S-II-Spread, High Luminance: Includes smallarea sources, such as incandescent or highintensity discharge. An open-bottom, deep-bowl diffusing reflector with a high-intensity discharge lamp is an example of this type.
• Type S-III-Spread, Moderate Luminance: Includes all fluorescent units having a variation in luminance greater than two-to-one.
• Type S-IV, Uniform Luminance: Includes all units having less than two-to-one variation of luminance. Usually this luminance is less than 640 candelas per square foot. An example of this type is an arrangement of lamps behind a diffusing panel.
• Type S-V, Uniform Luminance With Pattern: A luminaire similar to Type S-IV, except that a pattern of stripes or lines is superimposed.
Portable Luminaires. Whenever possible, supplementary luminaires should be permanently mounted in the location to produce the best lighting effect. Adjustable arms and swivels will often adapt the luminaires to required flexibility. Portable equipment (see Table 3-7), however, can be used to good advantage where it should be moved in and around movable machines or ob- Jects, such as in airplanes, or where internal surfaces should be viewed. The luminaires should be mechanically and electrically rugged to withstand possible rough handling. Lamps should be guarded and of the rough-service type. Guards or other means should protect the user from excessive heat. Precautions should be taken to prevent electrical shock. Cords should be rugged and insulation should conform to environmental requirements.
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TABLE 3-7. TYPICAL PORTABLE LUMINAIRES FOR SUPPLEMENTARY LIGHTING (Sheet 1 of 7) (Courtesy of McMaster-Carr Supply Company)
ADJUSTABLE ARM LIGHTS
a. Gooseneck Lights. These lights have an adjustable gooseneck and are available with high-intensity or standard incandescent lamps. They are also available with magnetic base, table base, C-clamp mount, and explosion-proof housings. They operate on 120V AC.
b. Floating Arm Lights. These lights are available with high-intensity fluorescent or standard incandescent lamps and have a floating arm that is adjustable by lightly touching with a finger. They are also available with magnetic base, caster base, weighted base, table base, universal mount, and waterproof or explosion-proof housings.
They operate on 120V AC.
c. Adjustable High-Intensity Lights. This has a five-position switch that provides varying light intensities. The arm has an 18-inch reach and swivels 360° horizontally and vertically, eliminating wire twist. It operates on 120V AC.
d. Clip-On Lights. These lights are available with high intensity or standard incandescent lamps and have a spring-loaded clip to attach practically anywhere.
Lights have an adjustable shade to allow directing of light beam. They operate on 120V AC.
PORTABLE UTILITY LIGHTS Caddy-Mounted and Tripod-Base Lights.
Caddy-mounted and tripod-base lights are available with standard incandescent, fluo- apar rescent and high-intensity lamps. They operate on 120V AC.
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TABLE 3-7. TYPICAL PORTABLE LUMINAIRES FOR SUPPLEMENTARY LIGHTING (Sheet 2 of 7) (Courtesy of McMaster-Carr Supply Company) PORTABLE UTILITY LIGHTS (Continued)
b. Self-Powered Flood Lights. Selfpowered lights are available with gasoline or diesel engines and metal malide or highpressure sodium lamps. They have a telescoping base that is adjusted with a winch and two semi-pneumatic tires. They are available with 120- and/or 240-V AC outlets.
High Pressure Sodium Light Cart. The light cart produces high-intensity lighting with a wide-angle beam. The light has a tempered glass lens with a wire guard and the cart has two 10-inch wheels and a heavy-gauge steel frame with a handle for easy portability. The cart operates on 120V AC.
d. Polygon Quartz Halogen Floodlights. A polygon-shaped frame can be positioned on any of five sides to aim the light beam where it is needed. A halogen lamp is suspended between springs for maximum impact and vibration resistance. It operates on 120V AC and is UL listed for wet locations inside and outdoors.
fights have up to 500 wạtts of high- intensity illumination in rugged easy to High-Intensity Floodlights. These carry units with fixed or bolted-down swivel base. They operate on 120V AC.
£ . Explosive-Proof Floodlight. This floodlight has a cast aluminum housing with a heat and impact-resistant glass lens.
The light moves 135° vertically in a yoke and the base swivels 360° and can be bolted down, It uses incandescent medium-base spot or flood lamps and also accepts reflector spot or flood lamps. It operates on a maximum of 600V AC and it is UL standard 844 listed Class I Groups C and D for 150- watt lamps and Class I, Group B for 300- watt lamps.
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TABLE 3-7. TYPICAL PORTABLE LUMINAIRES FOR SUPPLEMENTARY LIGHTING (Sheet 3 of 7) (Courtesy of McMaster-Carr Supply Company) PORTABLE UTILITY LIGHTS (Continued) Fioodlight Corrosion-Resistant Floodlights. is suitable for use in damp, This corrosive conditions. The fixture has a protective wire guard, a locking base, and a plastic carrying handle. It operates on 120V AC and UL listed.
INCANDESCENT TROUBLE LIGHTS General-Purpose Trouble Light. These general purpose heavy duty lights use 100- watt incandescent lamps. They operate on 120V AC, meet OSHA specifications and are UL listed.
Rights are available with a tempered glass or plastic globe that screws into the han- Vapor-Proof Trouble Lights. These dle to form a vapor-proof seal. They use a 100-watt lamp and operate on 120V AC. They are UL listed for enclosed and gasketed fixtures and meet OSHA and National Electrical Code (NEC) requirements.
c. Flood and Spot Trouble Light. This light uses a flood or spot lamp and has a welded metal guard. This trouble light operates on 120V AC, meets OSHA specifications, is UL listed and CSA approved.
d. Magnetic Base Trouble Lights. These trouble lights can be hung by a swivel hook or attached to a ferrous surface with a magnet built into the handle base. They operate on 120V AC, use a 75-watt bulb and are UL listed.
Hazardous Location Trouble Light.
trouble light is spark and weather tant with an aluminum guard and swivel listed for Standard A21 incandescent It operates on 120 volts AC.
to 100 watts and Class II, Group G using a 75-watt A21 lamp.
Coiled Cord Trouble Light.
ble light has a coiled cord that resists kinks and knots. The 75-watt light operated on 125V AC. meets OSHA specifications for general use and is UL listed.
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TABLE 3-7. TYPICAL PORTABLE LUMINAIRES FOR SUPPLEMENTARY LIGHTING (Sheet 4 of 7) (Courtesy of McMaster-Carr Supply Company) INCANDESCENT TROUBLE LIGHTS (Continued) Trim-Line Nonconductive Trouble Light.
This light is completely insulated and won't spark. The light has a flexible, oilproof rubber handle and a tubular nylon guard. The light uses a 7C7 7-watt incandescent lamp and operates on 120V AC.
FLUORESCENT TROUBLE LIGHTS
a. Watertight Trouble Lights. These lights have a butyrate shield and neoprene rubber end cap and handle seal to keep out water and dampness. They have hinged hooks on the end cap and handle that allow them to be easily positioned in the work area.
They are available with 20-watt or 40-watt T-12 fluorescent lamps, operate on 120-V AC and are FM approved.
fight slips into hard-to-reach, hard-to- Coiled Cord Trouble Light. This small light places. It has a coiled tangle resistant cord that extends up to 13 feet.
butyrate shield protects the lamp from direct contact. It is available with 6-watt and 8-watt T-5 fluorescent lamps.
ates on 120V AC and is FM approved.
fiuorescent light can be stuck to ferrous surfaces and has an arm and adjustable Magnetic Base trouble Light.
bracket for quick secure positioning. It has an 8-watt lamp protected by a shatterproof plastic tube. It operates on 120V AC and is UL listed.
₫. Compact Trouble Light. The 4-watt model has no exposed metal beyond the ballast; 8-watt model has a grounded metal reflector. It is available with a magnetic holder. Lights come with an 18-foot SJ cord and plug. The diameter is 1 5/16 inches and the length is from 10 inches (4 watt) to 15 inches (8 watt). It operates on 120V AC.
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TABLE 3-7. TYPICAL PORTABLE LUMINAIRES FOR SUPPLEMENTARY LIGHTING (Sheet 5 of 7) (Courtesy of McMaster-Carr Supply Company) FLUORESCENT TROUBLE LIGHTS (Continued) Cordless Rechargeable Trouble Light.
This light provides the convenience of going anywhere without the hassle of an electrical cord. The light operates for about two hours before needing a recharge and can be recharged in three hours. It had a 6- watt 3.6 halogen lamp, protected by a stainless steel wire guard. The body is made of durable antishock plastic.
length is about 14 inches. Lights come with three 1.2V rechargeable nickel cadmium batteries with a rated life of 8 years.
is available for use with 120V AC or 12V DC and comes with a battery charger. It is UL Compact Twin-Tube Trouble Light. The light has a 13-watt double tube fluorescent lamp to provide twice the illumination of other lights of the same size. It has a rubber handle and end cap and impact resistant plastic tube shield with built-in reflector. The overall size is 14 inches long by 2 9/16 inch diameter. It operates on 120V AC and is UL listed and CSA certified.
g - Hazardous Location All-Purpose Trouble Light. This light has a non-sparking all aluminum body with annealed glass lamp shield and built-in reflector. The lamp is protected by shock absorbers and an aluminum guard. The light is 27 inches long by 3 1/4 inch diameter with a 15-watt T-8 1amp. It meets National Electrical Code Class I, Div. 1 and 2, Group D; Class II, Div. 1 and 2, Groups E, F, and G; Class III, Div. 1 and 2. The cord, ballast, and lamp unit are FM approved.
Hazardous Location Compact Twin-Tube Trouble Light. The light has bumper guards falling objects, bumping'is protected by an and end caps to protect against damage from and dropping.
The annealed glass globe aluminum guard. It is 14 3/4 inches long by 3 1/2 inch diameter and comes with a 16/3 so cord and 13-watt lamp. It operates on 120V AC, is FM approved, and meets National Electrical Code Class I, Div. 1, Groups C and D; Class II, Div. 1, Groups E, and G; and Class III, Div. 1 Chap 3 Par 301 Page 93
TABLE 3-7. TYPICAL PORTABLE LUMINAIRES FOR SUPPLEMENTARY LIGHTING (Sheet 6 of 7) (Courtesy of McMaster-Carr Supply Company)
FIBBER-OPTIC ILLUMINATORS a . Quartz Halogen Fiber-Optic Illuminator. The illuminator is used to produce a high-intensity light beam from the tip of fibber optic bundles to light hard-to-reach places. The light is cold after it passes through a fiber-optic light guide, which keeps heat away from the point of inspection.
The illuminator is equipped with a basic 0.625 inch opening with reducer bushings provided for adaptability to various other lights guides. It has a variable intensity control with preset divisions to allow for repetitive presettings. The lamp is 150 watt, 3350° Kelvin, 21V. Fiber-optic guides and accessories are normally ordered separately.
b. Xenon Fiber-Optic Illuminator. This illuminator is twice the brightness of the above quartz halogen unit. It is meant for applications where an ultra-high intensity light source is necessary such as long borescopes that use fiber-optic illumination or for illuminating light absorbing materials.
The unit operates on 110V, 50/60-hertz AC, 6.2 amps. The lamp is a 300 watt, 6000° Kelvin, 35 to 50V DC. Fiber-optic accessories are normally ordered separately.
FIBBER-OPTIC LIGHT GUIDES a . Flexible Light Guides. These light guides are made to be used with fiber-optic illuminators. These light guides are flexible and will not support themselves. They are generally used in applications where the light guide has to be fastened to a part that is movable or they are used with a light guide stand.
b. Light Guide Stand. A light guide stand allows a flexible fiber-optic light to be positioned where it is needed and also has an adjustable lens that projects a clear circle of light that can be adjusted from a large area to an intense spot. The stand has 6 1/4-inch vertical travel and 2-inch horizontal travel at the base, and 5 1/2-inch travel at the lens barrel. It also features 360° vertical and horizontal rotation.
c. Free-Standing Light Guides. These light guides are made to be used with fiber-optic illuminators and are adjustable at any angle to the workpiece.
They can be used as secondary lighting to built-in illumination systems where the primary light source is insufficient due to long working distances or light absorbing workpieces. They are available in single or double styles.
TLLUMINATION ACCESSORTES
a. Ring Illuminators. Ring illuminators are made to be used with fiberoptic illuminators. They provide a circle of light over 360° leaving no shadow pockets, which is not possible with other illumination systems. The ring illuminator can be used as the prime light source for measuring microscopes, monocular, or sterno-viewing microscopes. or as a secondary light source for profile projectors, 35-mm cameras or closed-circuit TV systems.
b. Micro-Probe Illumination. These illumination systems are used with fiber-optic illuminators and are used in illuminating ultra-small holes and cavities that pose special viewing problems. Available probe diameter are
0.032 and 0.120 inch.
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TABLE 3-7. TYPICAL PORTABLE LUMINAIRES FOR SUPPLEMENTARY LIGHTING (Sheet 7 of 7) (Courtesy of McMaster-Carr Supply Company) ILLUMINATION ACCESSORIES (Continued) Co-Axial Illuminator. A co-axial illuminator is used with fiber-optic illuminators. It can illuminate the workpiece 10 to 12 inches and further from the lens system. It is used where the workpiece needs illumination where a deep cavity is involved that the present ring illuminators or separate fiber-optic bundles cannot illuminate properly as they are off the optical axis. The unit is used for machine vision video applications, optical comparators as well as microscope usage provided that there is sufficient microscope working distances.
Back Light Illumination System. The illuminator is used with fiberoptic illuminators. It illuminates an area of 3 square inches and can be switched from bright field to dark field by a simple control knob on the side of the unit. It can be used as an inspection tool for electronics where dark field illumination is desired and it can be used as background illumination for various microscopes and video applications.
Flashlights. Flashlights used for aircraft inspection should be suitable for industrial use and, where applicable, safety approved by the Underwriters Laboratory or equivalent as suitable for use in hazardous atmospheres. Military Specification MIL-F-3747E, Flashlights: Plastic Case, Tubular (Regular, Explosion-Proof, Explosion-Proof icat Resistant. Tras.
fic Directing, and Inspection-Light) provides requirements flashlights suitable for use in aircraft inspection. However, at the present time, the flashlights covered by this specification use standard incandescent lamps, and there are no standardized performance tests for flashlights with the brighter bulbs (Krypton, Halogen and Xenon). Each flashlight manufacturer currently develops its own tests and provides information on its products in its advertising literature. Therefore, when selecting a flashlight for use in visual inspection, it is sometimes difficult to directly compare products. The following characteristics should be considered when selecting a flashlight: footcandle rating, explosive atmosphere rating, beam spread (adjustable, spot, or flood), efficiency (battery usage rate), brightness after extended use, rechargeable or standard batteries, if rechargeable, how many hours of continuous use and how long for recharging. If possible, it would be best to take it apart and inspect for quality of construction and to use the flashlight as it would be used in the field. inspection flashlights are available in several different bulb brightness levels:
a. Standard incandescent for long battery life; b. Krypton for 70 percent more light than standard bulbs; c. Halogen for up to 100 percent more light than standard bulbs; and d. Xenon for over 100 percent more light than standard bulbs. Table 3-8 shows some of the typical types of inspection lights that are available.
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TABLE 3-8. TYPICAL INSPECTION FLASHLIGHTS (Sheet 1 of 5) (Courtesy of McMaster-Carr Supply Company) Ribbed-Grip Flashlight. This flashlight has a ribbed-grip and a highimpact thermoplastic body that resists oll, grease, chemicals, corrosion. and It is available with standard filament bulbs or Krypton bulbs.
explosion-proof only with the standard bulb and uses 2 or 3 D-cell batteries.
Underwriter laboratories (UL) listed Class I Groups C and D (hazardous vapors and gasses), and Class II Group G, Mine Safety and Health Association (MSHA) approved. The three D-cell model meets American Society for Testing and Materials (ASTM) F1014-86 Type III.
This flashlight is shitable for use in Explosive Atmosphere Flashlight.
an explosive atmosphere and has a highimpact ABS resin body. It uses Xenon bulbs and 3 or 4 C-cell batteries.
three cell model has a pocket clip, hanging ring, and wrist lanyard.
four cell model features a backup satety switch and adjustable beam for spot to Factory Mutual (FM) and Mine Safety and Health Association (MSHA) approved, Class I Groups A, B, C, and D.
Canadian Standards Association (CSA) certified.
Explosive Atmosphere Penlight.
flashlight has a polycarbonate resin body and pocket clip. It is FM approved. Class I Groups A, B, C, and D.
Class II Group G. Class III Div. 1 and
2. CSA certified.
d. Flexible Light Tool Kit. This light tool kit includes: penlight with extension mirror 1/8-inch-diameter by 10-inch flexible shaft six-inch handle and recovery magnet.
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