How We Test UV Flashlights
Every flashlight goes through the same testing framework so you can compare what it actually does—not how it is marketed.
See the Test Process ↓If the process changes from light to light, the comparison stops meaning much. So we keep the framework consistent.
01
Start fully charged.
Every test begins with a full charge so a weak battery does not decide the result.
02
Measure beyond startup.
We record the full continuous-output run instead of relying on one impressive first reading.
03
Test distance separately.
After burn-in, UV irradiance is measured at fixed distances using the same distance-test method.
04
Report every light the same way.
The same metrics and reporting format are used across tested models so you can compare the measurements yourself.
No single number tells the whole story. We measure the parts that answer different buyer questions.
01
UV Energy
Cumulative UV delivered during the continuous-output test. We scale this into the UV Energy Index for easier comparison.
02
Sustained Output
How well UV output holds over time. This is what the power curve and 30-minute retention show.
03
Distance
How much measurable UV reaches the sensor at fixed distances from 10 to 40 feet.
04
Operating Time
How long the flashlight remains powered on before shutdown, capped at 12 hours. This is separate from UV strength.
Continuous-output behavior and long-distance irradiance are different measurements, so we use different instruments for each job.
Continuous Output Testing
The LS128 records the continuous-output test while the flashlight runs. That lets us see what happens after startup, how well output holds, and how the light behaves over time.
This test produces the data behind our UV Energy Index, retained-output results, and power curves.
Distance Testing
The LS135 measures UV irradiance at fixed distances after burn-in. This shows how much measurable UV reaches the sensor as the flashlight moves farther away.
Distance results are recorded in µW/cm² and kept separate from the continuous-output test.
Duration Test
Operating time is measured separately: a fully charged flashlight is left running continuously until shutdown or the 12-hour test cap. Staying on longer does not automatically mean maintaining stronger UV output.
We publish the results so you can compare tested flashlights yourself. Pick two lights, look at the measurements, and check our work.
Compare UV Test Results →Full Test Library
See the published measurements, power curve, distance results, and technical record for any tested flashlight.
