What IP67 and IP68 Actually Cover on a Vehicle Lamp

Reading the Two Digits

The first digit covers solid particles and the second covers water. A 6 in the first position means dust tight, tested under vacuum, which is the level nearly all outdoor vehicle lighting is built to. In the second position, 7 means temporary immersion under defined conditions and 8 means continuous immersion to a depth the manufacturer states.

Where IP67 Is Enough and Where It Is Not

An interior ceiling lamp in a crew cab or a caravan lives in a dry space, and IP67 covers the occasional splash or condensation cycle it will see. A lamp mounted on a tractor fender that goes through a pressure wash after harvest is a different case. Dantech lists IP67 on interior and signal models and IP68 across the outdoor work, agricultural, driving and bar ranges.

What the Rating Leaves Out

Pressure washing is not an IP test. A jet at close range applies far more pressure than any immersion depth in the standard, and it is aimed at exactly the seams a lamp is weakest at. Salt spray, UV exposure and repeated thermal shock are separate concerns, which is why housing material and coating matter as much as the rating.

Why the Housing Specification Matters

Die-cast aluminium with a UV stable polyester powder coat resists chalking and corrosion far longer than a painted or plated finish. A polycarbonate lens takes a stone strike that would shatter glass. Both appear on the Dantech outdoor range, and both do more for service life in the field than the difference between IP67 and IP68.