What does an IP rating mean? Flashlight water resistance in practice

On a flashlight box you see a code like IPX4, IP65 or IP68 – and you often decide by it whether the light will survive rain or a drop into a stream. What exactly do those numbers mean, and when does marketing overstate them?

The first digit covers protection against solid particles, mainly dust, and runs from zero to six. The second covers water and runs from zero to nine. Both scales are cumulative – meeting a higher level means meeting all the lower ones.

When a manufacturer has not tested dust resistance, the first digit is replaced by an X. Hence the common “IPX4”. It is not a fault or an attempt to hide anything – simply an untested category.

This is where people get caught. IPX4 and IP44 offer the same water protection, but IP44 additionally has tested protection against solid particles over one millimetre. So when choosing between two lights with the same second digit, the one with a filled-in first digit has been measured in more respects.

Our range covers the whole spectrum and shows clearly what each level corresponds to: the FL1, FL3, FL4 and FL6 are IP44, the HL1 headlamp is IPX6, the FL5 and FL7 are IP67, and at the top sit the FL2 and the mini HL2 headlamp at IP68.

For ordinary outdoor use in rain and snow, IPX4 to IPX7 is plenty. Worry about IP68 only when you genuinely need to submerge the light for a long time – for instance with dive models, which also use magnetic or mechanical switching without weak points.

The price difference is rarely in the electronics but in the build: more seals, thicker glass, a different approach to the charging port. That is why the FL2 has no USB-C in the body and charges through a separate cell charger – a port under a flap is the weakest point at high ratings, so it simply is not there.

An IP rating is a laboratory test in clean, room-temperature water with no pressure beyond the prescribed depth. Out in the field a light meets things the test does not cover:

• Hot water and steam. Hot air inside the body condenses as it cools and draws moisture in. So do not wash the light in hot water or plunge it hot into cold.
• Salt water and chlorine. The standard does not test them, but they attack the anodised surface and the O-rings. After sea water, rinse in fresh.
• Ageing seals. The rating applies to a new product. A dried-out or dirty O-ring loses it, whatever is printed on the body.
• Impact. IP says nothing about impact resistance – that is a separate spec, quoted at one metre for the FL5, FL6 and HL1.

The water scale ends at nine, not eight. IPX9K means resistance to hot water at high pressure and is used mainly for equipment washed with a pressure washer – vehicles and industrial machinery in practice. You will not meet it on flashlights, and you will not miss it.

More interesting is that eight has no fixed depth. The standard says “continuous immersion under conditions specified by the manufacturer”, so IP68 on one light can mean two metres and on another twenty. If the light is meant for water, look in the specs for a specific depth and time, not just the pair of digits.

A higher rating costs something, and you do not always get more than you need. Decide by how you treat the light:

• For a pocket and the car IP44 is enough. Rain and splashes are all such a light will meet.
• For hiking and work you want IP67 – you can fish it out of a puddle and carry on.
• For water, mud and boats IP68 makes sense, along with a build without weak points – usually meaning no charging port in the body.
• On your head the rating matters more than it seems, because in rain a headlamp takes it the whole time, not just for a moment.

• Close the charging port flap right after charging – the quoted rating only holds with the flap shut.
• After changing the cell, tighten the thread all the way, not “almost”.
• After sea water, sand or mud, rinse the light in fresh water and let it dry open.
• Check the O-ring now and then; if it is dry, apply a thin layer of silicone grease, not petroleum jelly.
• Always blow or rinse sand out of the thread. Closing a threaded joint with sand in it is the fastest way to ruin the seal for good.

And watch one detail manufacturers do not mention: the rating usually holds only with the USB port closed and the head tightened. When in doubt, assume the light is exactly as waterproof as it is closed.

If you take one rule from this article: the first digit is about dust, the second about water, X means untested – and for nine people out of ten IP67 is more than enough. The rest is about how you treat the light, which we covered in the article on caring for your flashlight.