Guide to Choosing the Right FlashLight
If you ask yourself a few basic questions and answer based on the information provided here - you can choose a light that will serve you well for a long, long time.
Flashlight choice depends on intended use. Typically, there is no one light that works well in all situations. Consider your applications and the following basic questions:
- Is the work close up or is a long range beam required?
- Is the extraordinary bulb life and reliability of an LED needed or is the blinding power of a halogen or xenon bulb critical?
Flashlights come with several kinds of bulbs. The biggest differences are the amount of brightness, longevity of the bulb, and the cost. Hereâs a rundown of bulb choices:
INCANDESCENT - Both xenon and halogen lamps are considered incandescent style bulbs. They 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 - most powerful, highest performance, top choice for long distances.
LEDS (LIGHT EMITTING DIODES) - Solid-state construction. Very durable and long-lived - up to 100,000 hours. Do not require periodic replacement. Soft focus, short range. Good for close work. Typically much less power than incandescent lamp, but can give extremely long (100âs of hours) runtimes at low illumination levels. A downside to basic LED bulbs is that theyâre not especially bright.
Lumens and Candlepower
|"Lumens" of a bulb is a measurement of the entire output of the bulb. (Focus is not considered.)
||"Lumens" of LEDs is a measurement of all the light inside the "beam angle".
||"Peak beam candlepower" is a measure of the brightest spot in a focused beam.|
- Can the budget pay for disposable batteries or does frequent use demand rechargeable batteries?
Disposable or Rechargeable?
Disposable batteries, either alkaline or lithium, have excellent storage life, 7 and 10 years respectively. They generally offer longer runtimes for a given bulb power and are typically lower in initial purchase price and easier to keep spares on hand. Their operating costs are considerably higher than rechargeable batteries (see chart) and they are seldom as bright. Lithium cells have high energy density, but are even more costly than alkaline.
Rechargeable flashlights using nickel cadmium or lithiumion batteries feature extraordinarily low operating expense and are well suited for frequent use. They can often support a brighter bulb or LED and store conveniently in custom charger holders. Their initial purchase price is higher and they self discharge at a higher rate when in storage.
|Typical Costs of a Rechargeable vs. Disposable|
||Rechargeable Flashlight Costs
||D-Cell Flashlight Costs|
AMP The abbreviation for ampere and amperage. The unit used to measure electric current.
AMPERE-HOUR One ampere of current flowing for one AMPERE-HOUR One ampere of current flowing for one hour.
ANODIZING An electro-chemical coating for aluminum. Hard, durable, and attractive. Anodized parts are highly corrosion resistant.
ATEX European safety rating. ATEX products are rated for use in or around explosive atmospheres.
BI-PIN BULB A bulb with two contact pins that plug into a socket allowing easy replacement.
"BLACK DOT" BULB The Black Dot prevents stray light and gives the beam the ability to shine through dense mist, fog, and smoke.
BEAM CANDLEPOWER Also called Peak Beam Candlepower. Measurement of the brightest spot in a focused beam. An indication of the maximum intensity of the flashlight. The "hot spot" is equal in brightness to the number of "candles" required to produce the same illumination.
CANDELA Also called "candle." The unit of luminous intensity. One candela is equivalent to 12.57 lumens. At one time it was equal to the light from an actual burning "standard candle."
CANDLEPOWER When referring to flashlights, candlepower is usually the same as beam candlepower. CE Flashlights carrying this symbol meet applicable European Community Directives, and can therefore be sold in Europe.
DUAL FILAMENT A bulb that contains two filaments which enables users to instantly switch to the second filament when back-up lighting is needed.
HALOGEN AND XENON BULBS Flashlights using bulbs filled with these gases are recognized by their extreme brilliance and white light. These bulbs are generally more efficient than ordinary bulbs and may last longer.
HIGH TEMPERATURE LENS Typically made of borosilicate glass which has low thermal expansion characteristics. Easy to clean, resists scratching, and has good shock resistance when properly mounted.
INTRINSICALLY SAFE Not capable of igniting a flammable atmosphere under both normal and "fault" conditions.
L.E.D. (Light Emitting Diode) A high-intensity "solid-state" bulb which lasts up to 100,000 hours. Able to run for very long periods of time on very little power. Available in various colors including Ultra Violet.
LITHIUM Disposable batteries using lithium chemistry are gaining in popularity because of their light weight, high energy density, and shelf life of ten years.
LUMEN Unit of luminance. As used in reference to flashlights, it refers to the total amount of light radiated by the bare lamp, the LED, or the flashlight. Because this measurement does consider the focusing efficiency of the reflector, it does not indicate how "bright" the focused beam will appear. A flood lamp with a very wide dim appearing pattern can have the same lumen rating as a very tightly focused intensely bright spot lamp assembly. Lumen ratings cannot be converted to beam candlepower.
MACHINED ALUMINUM Flashlight components made from this material are lightweight, durable, and can be held to tight manufacturing tolerances for superior performance in precision assemblies.
NICKEL CADMIUM (abbreviated NiCd) The most common rechargeable battery used. It is the most rugged rechargeable technology and provides the highest performance/cost ratio. Must be recycled at end of life.
NON-INCENDIVE Not capable of igniting a flammable atmosphere under normal operating conditions.
NON-CONDUCTIVE Will not conduct electricity. Flashlights made with non-conductive case materials protect against electric shock should the flashlight touch an electrical source.
O-RING Used as a gasket to seal the flashlight case against dust and moisture.
POLYCARBONATE Clear, tough, shatterproof, virtually unbreakable polymer used to make the lens in many flashlights. Often hard coated for abrasion resistance.
POLYMER Material with a long chain molecular structure. Lightweight, highly durable, shock-resistant, non-conductive, and moldable in colors.
PRE-FOCUSED LAMP MODULE Lamp and reflector furnished and replaced as a unit. Permanently adjusted at the factory for optimum focus.
REFLECTOR Surrounds the lamp and directs and focuses the light rays in one direction.
VOLT Unit of electrical potential. The potential difference between two points in an electrical system is called the voltage between those points.
WATT Unit of power. Electrical power can be calculated by multiplying voltage times amperage.
2010 Guide information provided by Streamlight