Differences Between Damp and Wet Location Lighting

In high-humidity environments, using the wrong type of lighting can lead to safety risks like electrical shocks, short circuits, or fixture damage. That’s why it’s important to choose lights designed for moisture-prone areas.

You may heard of IP ratings, which indicate how well a light fixture is protected from dust and water. But when it comes to moisture exposure, there’s another important classification to consider: damp location lighting and wet location lighting. What are wet and damp location lighting? What are their differences?

Dry, Damp, and Wet Location Classifications

Before discussing damp and wet location lighting, it's important to understand electrical location classifications. Two main systems define these classifications: UL (Underwriters Laboratories) and NEC (National Electrical Code). These standards ensure that lighting installations are safe and suitable for their intended environment.

UL Classifications

UL (Underwriters Laboratories) is a globally recognized safety certification organization that sets standards for electrical products, ensuring they meet strict safety requirements. When it comes to lighting, UL classifications help determine whether a fixture is suitable for dry, damp, or wet locations.

Dry Location: An area that is not typically exposed to moisture but may experience temporary dampness, such as a building under construction. Proper ventilation is required to prevent moisture buildup.

Damp Location: An indoor or outdoor space where moisture can accumulate due to condensation, either on or near electrical equipment. This includes partially protected areas, such as covered patios or garages.

Wet Location: An area where water or other liquids can directly come into contact with electrical equipment due to dripping, splashing, or flowing. Wet-location fixtures must be designed to prevent water from accumulating on live parts, electrical components, or conductors unless they are specifically rated for water exposure. If water can enter the fixture, it must have a drain hole to prevent internal buildup.

NEC Classifications

The National Electrical Code (NEC), published by the National Fire Protection Association (NFPA), establishes safety standards for electrical installations. These classifications ensure lighting fixtures are suitable for their specific environments:

Dry Location: An area that is not normally exposed to moisture or water. However, it may experience occasional dampness or wetness, such as in a building under construction.

Damp Location: A space protected from direct exposure to weather but still subject to moderate moisture levels. This includes areas like certain interior spaces, such as some basements, barns, or cold storage facilities.

Wet Location: Environments where electrical components are directly exposed to water, such as underground installations, concrete slabs or masonry in contact with the earth, vehicle wash areas, and unprotected outdoor locations exposed to rain or other liquids.

What Is Damp Location Lighting?

Damp location lighting fixtures are designed for areas where moisture is present but without direct exposure to water or full submersion. These fixtures can handle humidity, condensation, and occasional light splashes without compromising performance.

To ensure durability, these fixtures are typically built with protective seals and moisture-resistant coatings, preventing water ingress, electrical shorts, and corrosion.

Damp-rated lighting is commonly used in covered outdoor areas where fixtures are shielded from direct rain or snow. Examples include recessed lights under canopies and outdoor wall-mounted fixtures that provide illumination for larger spaces.

In industrial and outdoor environments, damp location lighting is widely used in parking garages, tunnels, mining operations, and cold storage areas, where exposure to moisture is common but not extreme.

What Is Wet Location Lighting?

Wet location lighting fixtures are designed to withstand direct exposure to water, making them essential for environments where they may come into contact with rain, splashes, or other moisture sources.

These fixtures are fully sealed to prevent water from entering and compromising electrical components, ensuring safe and reliable operation. They undergo rigorous testing to ensure they can withstand direct water jets, immersion, and prolonged exposure to moisture without posing electrical hazards. Because of these requirements, wet location lighting often carries an IP (Ingress Protection) rating, typically ranging from IP65 to IP68.

Wet-rated lighting is commonly used in car washes, stadiums, offshore rigs, parking lots, and other outdoor or industrial settings where exposure to water is unavoidable.

What Are the Differences Between Damp and Wet Location Lighting

In simple terms, damp location lighting is designed to handle moisture and humidity but is not meant for direct exposure to water. In contrast, wet location lighting is built to withstand direct contact with water, including rain, splashes, or even immersion.

To provide a clearer comparison, here is a table outlining the key differences between damp and wet location lighting:

Can I Use Damp-Rated Lights in a Wet Location?

No, damp-rated lights should not be used in wet locations. While they can handle humid or moist environments, they are not designed to withstand direct exposure to water. Using damp-rated lights in wet locations could lead to safety hazards or damage to the fixtures. For areas exposed to water directly, always choose wet-rated lighting.