Wet Location, Damp Location and IP Ratings Explained

Two different systems are printed on the same spec sheet and they are not measuring the same thing. One is a safety listing that an inspector cares about. The other is an ingress protection number that tells you how long the fixture will actually survive. You want both.

UL location listings

This is the North American safety listing. It appears on the label and it is what an electrical inspector looks for.

Listing Means Typical locations
Dry Not normally subject to moisture Offices, retail, conditioned interior
Damp Moisture present but no direct water contact Covered porches, soffits, canopies, bathrooms, some basements, unconditioned covered storage
Wet Direct exposure to water, including driven rain and washdown Exposed exterior, parking garages, car washes, food processing, anywhere hosed down

Wet covers damp. Damp does not cover wet. A wet location fixture can go anywhere. A damp location fixture on an exposed exterior wall will take water at the gasket, and the failure will not be a warranty claim because the fixture was misapplied.

The cases people get wrong

  • Parking garages are wet, not damp. They have a roof, but cars carry water and snow in, floors get washed, and wind drives rain into the perimeter bays.
  • Under a canopy is usually damp, sometimes wet. A deep fuel canopy is damp. A shallow entry canopy that takes driven rain is wet.
  • Unheated warehouses can be damp. Condensation forms on cold surfaces when warm air comes in through a door. A dry location fixture in that space will see water on its inside surface.
  • Walk in coolers and freezers are wet. Door cycling and defrost make sure of it.

IP ratings

IP is an international two digit code. First digit is solids, second is liquids. Higher is more protected. Unlike the UL listing, it tells you how much water and how it is applied.

Rating Protection Use for
IP20 Fingers only, no water protection Interior dry only
IP44 Splashing water from any direction Covered exterior, damp interior
IP54 Dust protected, splashing water Light industrial, dusty but dry
IP65 Dust tight, low pressure water jets The practical minimum for exposed exterior and vapor tight interior
IP66 Dust tight, powerful water jets Washdown areas, car washes, food processing, coastal exposure
IP67 Dust tight, temporary immersion Ground level fixtures, areas that can flood
IP68 Dust tight, continuous immersion Submerged applications

How to read the two digits

IP66 and IP67 are not simply ranked, they test different things. IP66 is about pressurised jets. IP67 is about being briefly underwater. A fixture that survives immersion is not automatically rated for a pressure washer aimed at its gasket. Where both matter, look for a fixture that carries both ratings explicitly.

The other ratings that decide the job

IK, impact

IK08 and above matters in parking garages, loading docks, gyms, schools and anywhere a forklift mast or a basketball can reach the fixture. A polycarbonate lens survives what an acrylic one does not.

Ambient temperature range

Every lumen and life figure on a spec sheet was measured at 25 degrees Celsius. Real installs are not. Check both ends.

Space Watch for
Freezer, minus 20C and below Confirm the low end of the driver rating. LEDs like cold, drivers and gaskets do not always.
Unheated northern warehouse Low end rating, plus condensation as doors cycle
Uncooled southern warehouse High end rating. 40C or 50C rated drivers last materially longer.
Attic, roof deck, boiler room High end rating and clearance from the hot surface

Corrosion

An IP rating says nothing about corrosion. Within a few miles of salt water, near pools, at wastewater plants and in some food processing, a standard powder coated aluminium housing will chalk and pit, and the failure eventually shows up at the gasket. Ask for salt spray test hours, and look for marine grade or stainless hardware on anything exposed.

NSF and food safe

Food processing and commercial kitchens may require NSF certified fixtures. That is a separate listing from wet location and it covers shatter containment and cleanability, not just water. Ask before you spec.

What to specify by space

Space Specify Fixture
Exposed exterior wall Wet, IP65 minimum Wall packs
Parking lot pole Wet, IP65 Area lights
Parking garage Wet, IP65, IK08 Vapor tight or canopy
Car wash Wet, IP66, corrosion resistant Vapor tight
Food processing washdown Wet, IP66, NSF if required Vapor tight
Walk in cooler or freezer Wet, low ambient rated driver Vapor tight
Covered canopy or soffit Damp minimum, wet if exposed edge Canopy
Unheated warehouse Damp minimum, check low ambient High bays
Conditioned office Dry Panels

Before you order

  • Find the listing on the spec sheet, not the product title. Product titles are marketing. The label and the spec sheet are the record.
  • Check both ends of the ambient range. It is the most commonly ignored number on the page and it is the one that shortens life.
  • Match the gasket to the cleaning method. If the building washes fixtures with a pressure washer, IP65 is not enough.
  • Ask about corrosion separately. IP does not cover it and coastal buildings will find that out for you.
  • Confirm the mounting seals too. A wet rated fixture on an unsealed penetration still lets water into the box.

Every fixture on this site carries its listing on the product page, and the manufacturer spec sheet is linked from it. If a rating you need is not shown, ask and we will get it from the manufacturer rather than guessing.

40 vapor tight fixtures, wet location rated

For washdown areas, parking garages, car washes and cold storage. Gasketed, IP65 and IP66, with the rating on every product page.

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