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ANSI FL1 Standard

FL1 Standard – these specifications can be found on the packaging of most flashlights today. What do these specifications mean for you, and how can you interpret this information? Since we started including runtime graphs in our reviews, we’ve gotten a lot of questions about the ANSI FL1 Standard, so this article is intended to give you a better understanding of the technical aspects of flashlight performance.

ANSI/NEMA FL 1-2009 Standard
Commonly abbreviated as the ANSI FL1 Standard, the ANSI/NEMA FL 1-2009 Standard is a set of flashlight performance guidelines. Before the introduction of these standards, you may have seen variety of phrases on flashlight packaging, such as these:

*  “3W LED” was a common term used when high performance LEDs, such as the Luxeon, were first introduced. LEDs have varying efficiencies and rarely operate at the rated power, so this doesn’t really have any meaning.
*  “1 million candlepower” (or any other multiple of a million), is often seen on lanterns and spotlights. A million of anything is impressive, but how bright is one million candles?
*  “High-flux LED” is really just a fancy way to say that the LED is bright, but even if you’re an engineer, it still doesn’t have much meaning to it.

With the FL1 Standard, ambiguous marketing phrases are a thing of the past, and direct comparisons can be made between flashlights from different manufacturers. Adherence to the FL1 Standard is voluntary, although the vast majority of manufacturers have adopted the standard. Here’s how the ratings are defined:

Light Output [Lumen]
Light output is a measurement of luminous flux using an integrating sphere. The unit of luminous flux, lumen, is a measurement of energy.
Peak Beam Intensity [Candela]
Peak beam intensity is a measurement of luminous intensity at the middle of the flashlight beam. The unit of luminous intensity, candela, is a measurement of energy.
Beam Distance [Meter]
Beam distance is defined as the distance from the flashlight where illuminance is equivalent to a full moon on a clear night.
Runtime [Hours]
Runtime is defined as the amount of time, rounded to the nearest quarter hour, until output drops below 10%.
Water Resistance [IPX Rating]
Water resistance is stated using the IP rating system, and three ratings are used.
*  IPX4 – water-resistant, or water splashed from all directions
*  IPX7 – water-proof, or temporary submersion at 1 meter for 30 minutes
*  IPX8 – submersible, or continuous submersion at some specified depth for 4 hours
Impact Resistance [Meter]
Impact resistance is tested with drops onto a concrete surface at the specified height with all intended accessories, including batteries, installed.

Color Rendering Index

CRI is a quantitative measure of the ability of a light source to reveal the colors of various objects faithfully in comparison with an ideal or natural light source. Light sources with a high CRI are desirable in color-critical applications such as neonatal care and art restoration.