ANSI/NEMA FL-1: Flashlight Performance Standard

The standard that defines how flashlight specs are measured. Lumens, candela, beam distance, runtime, impact resistance, and IPX ratings, all tested the same way so you can compare products side by side.

Last updated: April 7, 2026

Overview

ANSI/NEMA FL-1 is the North American standard for measuring portable flashlight performance. Published by the National Electrical Manufacturers Association (NEMA) and accredited by ANSI, it defines exactly how to test and report the specs that show up on flashlight packaging: lumens, candela, beam distance, runtime, impact resistance, and water resistance.

Before FL-1 came out in 2009, flashlight manufacturers could test however they wanted. One company's "200 lumens" might be measured fresh off the production line at peak output, while another measured after 30 seconds of runtime with fully stabilized output. There was no way to compare products. FL-1 fixed that by creating a single set of test methods everyone follows.

The standard was updated in 2016 to add clarity on measurement procedures, and again in 2019 (Edition 2.0) to address LED-specific testing considerations. It covers all portable battery-powered lighting, including handheld flashlights, headlamps, and lanterns.

Why it matters: FL-1 is voluntary, not mandatory. But any manufacturer that claims FL-1 compliance must follow the test methods exactly. When you see the FL-1 icon on packaging (a standardized set of symbols with values), you know those numbers were measured using the same procedures as every other FL-1 tested light. If there is no FL-1 marking, the specs may have been measured under more favorable conditions.

Performance Metrics

FL-1 defines six core performance metrics. Each has a specific test method, measurement unit, and icon that appears on compliant packaging. All measurements start 30 seconds after the light is turned on, after initial brightness stabilization.

Metric	Unit	What It Measures	How It's Tested
Light Output	Lumens (lm)	Total amount of light emitted in all directions	Integrating sphere captures all emitted light at the 30-second mark
Peak Beam Intensity	Candela (cd)	Brightness of the hotspot, the brightest point in the beam	Measured at center of beam at a set distance, converted to candela
Beam Distance	Meters (m)	How far the beam reaches at 0.25 lux (equivalent to full moon illumination)	Calculated from peak beam intensity: distance = sqrt(candela / 0.25)
Runtime	Hours (h)	How long the light runs before output drops to 10% of initial	Continuous run from 30-second mark until output falls below 10% threshold
Impact Resistance	Meters (m)	Drop height the light survives while still functioning	Dropped 6 times from rated height onto cured concrete, must still operate
Water Resistance	IPX rating	Level of protection against water ingress	Tested per IEC 60529 at the specific IPX level claimed (splash, submersion, etc.)

The 30-second rule: All light output measurements start 30 seconds after the light is turned on. This lets the LED and driver circuit thermally stabilize. Without this rule, manufacturers could report the brief peak output that occurs in the first few seconds before thermal management kicks in.

Lumens vs Candela

Lumens and candela measure two different things, and understanding the difference is the key to picking the right flashlight for a job. Lumens measure total light output in all directions. Candela measures beam intensity in one specific direction, the center of the hotspot.

Think of it this way: a bare light bulb in the middle of a room produces high lumens but low candela because the light goes everywhere. Put a reflector behind that same bulb and aim it down a hallway, and the candela goes up dramatically even though the lumens stay about the same. You have not created more light, you have just focused it.

Typical Ranges by Flashlight Type

Flashlight Type	Typical Lumens	Typical Candela	Beam Distance	Best For
Compact/EDC	50-300 lm	500-3,000 cd	30-100 m	Everyday carry, close-range tasks
General work light	200-500 lm	2,000-8,000 cd	80-180 m	Maintenance, inspections, general use
Flood/area light	500-1,500 lm	1,000-5,000 cd	60-140 m	Work areas, painting, wide coverage
Tactical/duty	500-1,200 lm	10,000-30,000 cd	200-350 m	Security, search, law enforcement
Long-throw search	300-1,000 lm	50,000-200,000 cd	450-900 m	Search and rescue, long-distance ID

Beam distance is calculated from candela, not lumens. The FL-1 formula is: beam distance (m) = square root of (candela / 0.25). A 10,000 candela beam reaches 200 meters. A 40,000 candela beam reaches 400 meters. Doubling the candela does not double the distance; you need four times the candela to double beam distance.

IPX Water Resistance Ratings

The "IP" in IPX stands for Ingress Protection, defined by IEC 60529. The "X" means no dust rating is claimed (FL-1 only tests water resistance, not dust). The number after IPX tells you exactly what water exposure the flashlight survived during testing.

IPX Rating	Protection Level	Test Method	Practical Meaning
IPX0	No protection	No water test performed	Keep it dry
IPX1	Dripping water	Vertical drips for 10 minutes	Light condensation or drips
IPX2	Dripping (tilted)	Drips at 15° angle from normal position	Light rain while tilted
IPX3	Spraying water	Water sprayed at up to 60° from vertical	Rain from any normal angle
IPX4	Splashing water	Water splashed from all directions for 5 minutes	Heavy rain, splashing on a job site
IPX5	Water jets	6.3mm water jet from all directions for 3 minutes	Hose spray, washdown environments
IPX6	Powerful water jets	12.5mm water jet from all directions for 3 minutes	High-pressure washdown, heavy seas
IPX7	Temporary submersion	Submerged in 1 meter of water for 30 minutes	Dropped in water, temporary flooding
IPX8	Continuous submersion	Submerged beyond 1 meter for manufacturer-specified duration	Dive lights, underwater work

IPX ratings are not cumulative. An IPX7 rated flashlight has been tested for submersion, but that does not mean it passed the IPX5 water jet test. Submersion and jet spray are different kinds of water exposure. Some manufacturers test and list dual ratings (e.g., IPX5/IPX7) to confirm both types of protection. If only one rating is listed, that is the only test that was performed.

Runtime Testing

Runtime under FL-1 is measured from the 30-second mark (after initial stabilization) until the light output drops to 10% of its initial value. The light runs continuously on the mode being tested, using the batteries that ship with the product or the manufacturer-specified cells.

The 10% threshold is important. It means the runtime number on the package is not how long the light stays at full brightness. It is how long the light produces at least 10% of its starting output. What happens between 100% and 10% varies dramatically depending on the flashlight's driver circuit.

Output Curve Types

How a flashlight manages its output over time matters more than the headline runtime number. There are two common patterns:

Regulated (flat) output: The driver circuit maintains near-constant brightness for most of the runtime, then drops off sharply when the battery is nearly depleted. You get consistent light for a predictable duration, then the light dies quickly. Most professional-grade flashlights use regulated drivers.
Unregulated (gradual) output: Brightness starts high and slowly decreases as the battery drains. The light may still produce usable light well past the FL-1 runtime, but it gets progressively dimmer. Common in budget flashlights and some older designs.

Check the runtime graph, not just the number. Two flashlights can both claim "4 hours runtime" with very different real-world behavior. One might hold 90% output for 3.5 hours then cliff. The other might drop to 30% in the first hour and coast at low output until the 4-hour mark. Good manufacturers publish runtime graphs showing the output curve. If no graph is available, look for reviews that test runtime independently.

Impact Resistance Testing

The FL-1 impact resistance test is a drop test. The flashlight is dropped 6 times from the rated height onto cured concrete. Each drop lands the light on a different surface or angle. After all 6 drops, the flashlight must still turn on and function. There must be no cracks in the lens or body that would compromise the water resistance rating.

Drop Height	Typical Use Case	What to Expect
1 meter (3.3 ft)	General purpose, desk or belt height drops	Basic construction, survives everyday fumbles
1.5 meters (5 ft)	Work use, shoulder-height drops	Reinforced body, thicker lens, knurled grip
2 meters (6.6 ft)	Tactical, industrial, overhead work	Heavy-duty construction, aerospace aluminum or polymer, recessed lens

Impact resistance is not crush resistance. The FL-1 drop test checks whether the light survives being dropped. It does not test what happens if a vehicle runs over it, if it gets stepped on, or if something heavy falls on it. There is no FL-1 spec for crush or shock loading. If your work environment involves those hazards, look for lights with additional manufacturer crush test data or steel-bodied construction.

Choosing a Flashlight by the Numbers

Different jobs need different specs. Here are practical minimums based on common work tasks, using FL-1 metrics to make the decision straightforward.

Task / Use	Lumens	Candela	IPX	Impact	Notes
General maintenance	150+	Any	IPX4	1 m	Enough for panel work, overhead checks, crawl spaces
Electrical work	200+	Any	IPX4	1 m	Non-conductive body preferred, headlamp for hands-free
Confined space entry	200+	Any	IPX7	1.5 m	PLUS intrinsic safety per UL 913 if atmosphere may be hazardous
Outdoor construction	300+	5,000+	IPX4	1.5 m	Need throw distance for site work, survives rain
Security / patrol	500+	10,000+	IPX7	2 m	High candela for identification at distance, strobe mode
Search and rescue	500+	30,000+	IPX7	2 m	Maximum throw distance, extended runtime on lower modes
Hazardous locations	200+	Any	IPX7	1 m	Must be UL 913 certified for intrinsic safety, FL-1 specs are secondary

More lumens is not always better. A 1,000 lumen flood beam is useless for inspecting conduit at 50 feet. A 200 lumen focused beam with 10,000 candela will light up that conduit clearly. Match the light to the task. For close-up work in tight spaces, lower lumens with a wide beam prevents blinding reflections off shiny surfaces. For distance, candela matters far more than lumens.

Regulatory Connection

ANSI/NEMA FL-1 is a voluntary performance standard, not an OSHA regulation or NEC requirement. No law requires a flashlight to be FL-1 tested. However, several regulations create situations where the type of flashlight you use matters, and FL-1 specs help you verify compliance.

Hazardous Locations

In areas classified as hazardous under NFPA 70 (NEC) Articles 500-506, all electrical equipment, including flashlights, must be rated for the specific hazard classification. FL-1 does not cover intrinsic safety. That falls under UL 913, which certifies that the device cannot produce enough heat or spark energy to ignite a specific gas, dust, or fiber atmosphere.

OSHA 1910.106: Flammable liquid storage and handling areas require approved equipment. A standard flashlight is not approved for these locations regardless of its FL-1 rating.
NFPA 70, Articles 500-506: Define hazardous location classifications (Class I/II/III, Division 1/2 or Zone 0/1/2). Equipment used in these areas must be listed for the specific classification.

Confined Space Lighting

OSHA 1910.146 (permit-required confined spaces) requires adequate lighting for safe entry and work. While OSHA does not specify lumen counts, the flashlight must be appropriate for the space. If the confined space has a potentially hazardous atmosphere, the light must also be intrinsically safe (UL 913).

Electrical Workplace Safety

NFPA 70E addresses task lighting in electrical work environments. When working on or near energized equipment, flashlights with non-conductive bodies reduce the risk of creating a fault path. FL-1 does not test for electrical insulation properties, so this is a separate consideration from the FL-1 performance metrics.

FL-1 and UL 913 are separate standards. A flashlight can be FL-1 tested for performance AND UL 913 certified for intrinsic safety. They measure different things. FL-1 tells you how bright and durable the light is. UL 913 tells you it will not ignite a hazardous atmosphere. For hazardous locations, you need UL 913 certification. FL-1 specs just help you pick the right brightness and runtime among the intrinsically safe options.

Frequently Asked Questions

Is ANSI FL-1 testing mandatory?

No. FL-1 is a voluntary standard. No regulation requires flashlight manufacturers to follow it. However, any manufacturer that claims FL-1 compliance on their packaging must follow the test methods exactly as defined in the standard. The FL-1 icons and format are trademarked by NEMA, and misuse can be challenged.

What does "FL-1 tested" mean on packaging?

It means the manufacturer followed ANSI/NEMA FL-1 test protocols to measure the specs printed on the package. It is not a third-party certification. There is no FL-1 testing lab that stamps approval. The manufacturer conducts the tests (or hires a lab to do it) and self-declares compliance. Reputable brands stake their reputation on accurate numbers, but there is no independent verification requirement.

Why do some flashlights show two lumen ratings?

Many flashlights have multiple output modes (high, medium, low, turbo). FL-1 ratings are per-mode, so responsible manufacturers list the output for each setting. If a light lists "1,000 / 400 / 100 lumens," those are the FL-1 measured outputs for each mode. Runtime is also mode-specific, so a light might run for 2 hours on high and 20 hours on low.

Does a higher lumen count always mean a better flashlight?

No. Beam pattern, candela, runtime, and build quality matter more than raw lumen count for most work tasks. A 200 lumen flashlight with a tight, focused beam and 10,000 candela will throw light farther and illuminate a distant target better than a 1,000 lumen flood light. For close-range work in reflective environments (electrical panels, painted walls), high lumens can actually make things harder to see by creating glare.

What is the difference between IPX7 and IPX8?

IPX7 means the flashlight survived being submerged in 1 meter of water for 30 minutes. IPX8 means it is rated for continuous submersion at a depth and duration specified by the manufacturer (often 2 meters or more for extended periods). IPX8 is a more demanding test, but the exact parameters vary by manufacturer, so check their specific depth and time claims.

Do rechargeable flashlights test differently under FL-1?

The FL-1 standard does not differentiate by power source. Tests use the batteries that ship with the flashlight or the manufacturer-specified cells. For rechargeable lights, the battery is fully charged before testing. Runtime results may differ between battery types (lithium-ion vs alkaline vs NiMH) on lights that accept multiple cell types, so check which battery type was used for the published FL-1 specs.