How t o Choose t he Right F lashlight Flashlights now come in so many choices of styles, features, battery and bulb types that it is a task to figure out which flashlight will best suit your needs. Do you need rechargeable or disposable batteries? Which bulb—xenon, krypton, halogen, LED or standard incandescent—will best suit your application? Will you be in a hazardous location or situation where a hazardous location rated flashlight is needed? Following are breakdowns of the different flashlight options to help you decide. Battery Ty pes Rechargeable vs. Disposable: The situation can determine which type of battery is needed. Disposable batteries are usually lower in initial purchase price, which makes it easier to keep spares on hand. Typically, they are not as bright as rechargeables. Rechargeable batteries have a higher initial purchase price but are more economical to operate in the long run. They can often support a brighter bulb or LED and store conveniently in custom charger holders. The following information can help determine which type of battery is best for your use. Disposable: Alkaline—Are fairly inexpensive. However, performance is affected by heat and cold and the power curve drops off very quickly. They are at their brightest the first time they are used and decline rapidly thereafter. Lithium—Becoming more and more affordable. They are not affected by extreme heat and cold. They have a steady power curve over the life of the battery and have an extremely long shelf life of nearly 10 years. Rechargeable: (Nickel-Cadmium or Ni- Cd) —Is the most rugged rechargeable technology and proides the highest performance/cost ratio. New technology makes this battery more and more effective. This type must be fully charged so it does not develop a memory effect (does that at the bottom of the cycle and may occur as battery ages). These are rechargeable up to 1000 times. Must be recycled or disposed of properly. Lithium Ion—Rechargeable up to 1000 times with no memory effect problems. These batteries have a longer runtime and are more expensive than standard lithium batteries. They are environmentally friendly and can be thrown away. Sealed Lead Acid—Like a car battery. Not affected by heat or cold. Sealed lead acid batteries give extremely long runtimes but are fairly large in size. This type must be recycled or disposed of properly. Bulb Ty pes A big difference among flashlights is the bulb used and the light it projects. Also considered when choosing the bulb is longevity, cost and runtime of the bulbs. The different bulb types are described below. Incandescent Bulb Types: Krypton Bulb—Incandescent bulb filled with krypton gas. A very economical bulb but not as bright as a xenon or halogen bulb. Xenon Bulb — Incandescent bi-pin bulb filled with xenon gas. This bulb provides extremely bright light and is easily replaced. Xenon bulbs represent a good balance between cost and output. Halogen Bulb—Incandescent bulb filled with halogen gas. These are whiter and brighter than other incandescent bulbs. Both xenon and halogen lamps provide high output for their size and a white, natural- appearing light. Halogen lamps “blacken” less as they age and may have longer life than xenon. Both require periodic replacement and can fail on extreme impact. They are easily focused and are the most powerful, highest performance, top choice for long distances today. LED (Light Emitting Diodes) Types: LEDs are a computer chip-like device that emits light when power is added. The LED projects a wider, more dispersed light of 180 degrees. Solid-state construction makes LEDs very durable and long-lived—up to 100,000 hours of life. LEDs do not require periodic replacement like krypton, xenon and halogen lamps. Due to their soft focus and short range, LEDs are good for close work. Typically, LEDs provide much less power than incandescent lamps but offer the advantages of extremely long runtimes (hundreds of hours) at low illumination levels, unlike a xenon or halogen lamp that may have, at best, 5 to 9 hours of runtime. These solid-state lamps are also safer in hazardous environments. Tactical Tactical flashlights are typically more rugged, more reliable and more powerful than the standard flashlight. Tactical-rated lights can be used as add-on lighting to weapons or used on their own as a flashlight. These are used by the military, SWAT teams and police forces for that reason. With the above information on bulb and battery types, you can now ask yourself the following questions to help select the proper light: Is the work close up or is a long-range beam required? • If your work is close up, LEDs are probably a good choice. • If long runtimes and bulb life are important, LEDs are probably a good choice. • If you are looking for a long range and high light output, LED, krypton, halogen or xenon lights are probably a good choice. • Is cost of operation and continuous use a concern? If so, a rechargeable light may be a good choice. Light Measurement Candlepower (Peak Beam Candlepower)—A measurement of the brightest spot in the focused beam (usually @ 100 ft.). It is a function of both the output of the lamp and the efficiency of the reflector. The term “candlepower” (candelas) originates from an older unit, the candle, and was based on an actual candle of specified dimensions and construction. Lumens (Total Luminous Output)—A measure of the entire light output of the flashlight regardless of beam focus. It is almost solely a function of the lamp (bulb). This measurement is taken in a sphere and regarded as the most accurate of the measurements. Foot-candle (FC)—Density of light that falls on a surface. Equal to one lumen per square foot. Haz ardous Locat ions General-purpose electrical equipment can cause explosions in certain atmospheres. Equipment, such as flashlights, used in areas where explosive concentrations of dusts or vapors may exist must be equipped with specially designed switches, seals and other safety features. Hazardous (classified) locations might exist in areas such as aircraft hangars, gasoline stations, paint-finishing locations or agricultural areas such as grain bins. Firefighters typically use hazardous location-rated equipment also, because they are going into situations where the atmosphere is an unknown. Flashlights that are rated for these locations will have the class and division markings along with the third party approval stamped into the flashlight body. In order to make sure the correct equipment is used, these environments have been broken down into classes, divisions and groups to more specifically identify the hazards. SUMMARY OF CLASS I, II, III HAZARDOUS LOCATIONS DIVISIONS CLASSES GROUP 1 2 A. Acetylene I Gasses, Not normally present in B. Hydrogen, etc. Vapors and Normally explosive and an explosive C. Ether, etc. Liquids (Art. hazardous. concentration (but may D. Hydrocarbons, 501) accidentally exist). Fuels, Solvents, etc. E. Metal Dusts (conductive* and explosive) F. Carbon Dusts Ignitable quantities of Dust not normally (Some are dust that is normally or suspended in an ignitable II Dusts (Art. conductive* and all may be, in suspension, concentration (but may 502) are explosive) or conductive dust may accidentally exist). Dust G. Flour, Starch, be present. layers are present. Grain, Combustible Plastic or Chemical Dust (explosive) Textiles, III Fibers and Woodworking, etc. Stored or handled in Handled or used in Flyings (Art. (easily ignitable, but storage (exclusive of manufacturing. 503) not likely to be manufacturing). explosive) *Electrically conductive dusts are dusts with a resistivity less than 105 Ohm-centimeter.
Pages to are hidden for
"How to Choose the Right Flashlight Battery Types"Please download to view full document