In 2009 the American National Standards Institute (ANSI) published the “Flashlight Basic Performance Standard“ (FL1). Now you can compare flashlights of different manufacturers with neutral means.
All Walther Pro Lights are made and tested according to ANSI FL1.
Light Output (or Luminous flux): On flashlights with several brightness levels, the light output in lumens is measured at the highest level starting at 30 and ending at 120 seconds.
Beam distance: Distance at which an illuminance of 0.25 lux can still be measured – this is the amount of light on the ground from a full moon on a clear night, because this provides a certain feeling for a highly technical value.
Run time: Time after switch-on and continuous operation until the brightness is reduced to 10 percent, so that an average user will usually replace or recharge the batteries.
Enclosure Protection Against Water Penetration Ratings: Minimum requirements for the enclosure’s protection against water ingress and damage. All samples must function normally immediately after the test and also 30 minutes later.
Impact Resistance (Drop test): During the drop test in six different orientations, the sample must be switched off, but with all intended parts and additions (batteries, retaining straps, hand straps, etc.). The minimum drop height is 1 metre onto fully cured concrete. Higher drop heights can be used, but then all test samples must meet the requirements for this height.