When discussing product enclosures and their degree of ingress protection, it is important to note that there are two major electrical manufacturing organizations that monitor this. These organizations also publish the technical manufacturing standards and ratings for product enclosures. The two organizations are:

The National Electrical Manufacturers Association (NEMA) – addresses the following:

  • Non-hazardous locations
  • Enclosure design
  • Environmental performance

These are referred to as NEMA Type enclosures, which is a term often used in America.

The International Electrotechnical Commission (IEC) – addresses
only Ingress Protection (IP), not the enclosure itself. IP Codes/ratings support NEMA Type designations, and IP type is a term commonly used in Asia and Europe.

Each of the above electrical manufacturing organizations have systems in place which define ingress protection from solids and liquids entering a product enclosure. NEMA ratings take into account ingress protection of solid foreign objects and water, along with other specifics such as design details and corrosion resistance.

As for Ingress Protection ratings, they only take into account ingress protection of solids and liquids, therefore lacking the anti-corrosive element that NEMA type enclosures have. All that to say, NEMA ratings are equivalent to IP ratings, however, IP ratings are not equivalent to NEMA.

What Are NEMA Ratings and Why Do They Matter

The National Electrical Manufacturers Association was formed in 1926 when the Associated Manufacturers of Electrical Supplies and the Electric Power Club came together so as to set standards for the manufacturing of safe, effective electrical products.

The late twenties and early thirties saw a demand for regulations in the manufacturing setting to produce safer electrical products. NEMA met that demand and continues to do so in order to develop and promote standards for the ever-changing electrical industry.

New electrical equipment that will be installed outdoors or in an industrial setting must be capable of protecting the electrical equipment inside from its surrounding environment and the elements. Whether it is steam in a manufacturing facility or dirt and mud on the underside of a military vehicle, the electrical equipment will need an enclosure that is NEMA or IP rated. But what exactly does that mean? Also, what if the enclosure will be prone to partial or prolonged submersion. There are only two “NEMA rated” types of enclosure[s] for temporary to prolonged submersion, and they are NEMA6 and NEMA6P.

– NEMA6: Indoor and outdoor use/Capable of protecting against splashing water, windblown dust and rain, hose directed water, ice formation and temporary submersion at a limited depth.

NEMA6P: Indoor and outdoor use/Capable of protecting against splashing water, windblown dust and rain, hose directed water, ice formation, temporary submersion and prolonged submersion at a limited depth.

A NEMA-rated enclosure is capable of controlling ingress and egress. Ingress is a substance’s ability to enter, where as egress has to do with solids or liquids exiting a cabinet or enclosure. NEMA ratings deal mostly with ingress, however, there are several that do deal with egress prevention. To note, environmental exposure to water ranges from condensation moisture to wash-down with water under pressure to temporary and permanent submersion.

Why Are Cabinets and Enclosures NEMA Rated?

Even though NEMA set out to ensure the quality of electrical equipment, the technology and industry evolved, and yet another demand arose in the protection of said equipment. Enclosure[s] and cabinets, although not NEMA’s direct responsibility, were in need of a rating system so that they would effectively protect vulnerable devices. NEMA became the go-to standard for help in manufacturing enclosure[s] and cabinets with the right materials and design for particular applications.

Are NEMA Enclosure Ratings the Same as IP Ratings?

There is some correspondence between IP and NEMA ratings as we have previously mentioned, although each rating system uses a very different numbering scheme.
With IP ratings, they read as follows:

First digit of the IP Code: describes the degree of protection against the ingress of solids
Second digit of the IP code: designates the degree of protection against the ingress of liquids

For example, IP[68] means that it is dust tight (6) and can is rated for long term immersion up to a specified pressure (8). The Ingress Protection system is commonly used in Europe and Asia, but is increasingly being used in the U.S. IP standards for enclosure[s] are the international guideline, and come from the European Committee for Electrotechnical Standardization (CENELEC). Although American manufacturers may offer their products with IP ratings, this generally only appears on electrical cabinets and enclosure[s] made outside the United States.

Because NEMA and IP systems use different testing parameters, they are not easily converted or directly comparable. While close, the equivalencies of NEMA and IP should be used as a guide, not a rule. Here are some NEMA ratings with their closest comparable IP ratings:

NEMA 6: Provides ingress and egress protection/Will withstand occasional water submersion/Sleet-resistant and watertight
IP67: Complete protection against any dust ingress/Can maintain operation partially submerged between 0.49 ft (15cm) and 3.3 ft (1m).

NEMA 6P: Provides ingress and egress protection/Can withstand prolonged submersion
IP68: Lends total protection against water damage from submersion up to .49 ft (15cm) to 3.3 ft (1m)/Protects from dust ingress

Frequently Asked Questions

Q: Which enclosure should I use, a NEMA type or an IP type?

A: This will depend on your location. If in Europe and Asia, IP types are used because they are rated for ingress protection. In North America, NEMA type enclosures are more prevalent. However, more enclosure companies are standardizing to the IP rating.

Q: Do IP ratings consider temperature?

A: Most IP and NEMA tests are conducted at room temperature. The IP68 rating does have a specific temperature requirement.

Q: Are there IP and NEMA ratings for hazardous locations?

A: IP and NEMA ratings relate to all locations. For hazardous ratings, you want a higher rating so that there is no ingress of any type. This is especially true so that nothing could create a spark.

At SLAYSON®, we will help you manufacture project specific solutions to meet your exact application and environmental requirements. All of our product enclosure[s] are manufactured in accordance with ISO 9001:2015 testing and certified with our Certificate of Conformance. We consistently demonstrate the ability to provide products and services that meet our customer’s needs and requirements. SLAYSON® works with various industries around the world including:

  • Automation and Control
  • Maritime
  • Defense
  • Oil and Gas
  • Infrastructure
  • Tunnels and underground

We engineer, manufacture and assemble using the latest technology to deliver project specific NEMA 6P and IP68 submersible enclosures. SLAYSON® NEMA 6P & IP68 Submersible Enclosures are manufactured from either Marine Grade 316 Stainless Steel, Aerospace Grade Aluminium or Engineered Polyurethane Composite. Our enclosures protect against:

  • Corrosion (saltwater, chemicals, etc.)
  • Ingress of solids and liquids
  • EMI/RFI interference
  • High Impact and Crushing

SLAYSON® has the world’s most extensive range of Commercial Off The Shelf (COTS) NEMA 6P / IP68 Enclosures. Our entire range of enclosures can be customized or modified (MOTS) with a variety of standard accessories to create an engineered enclosure solution, specific to your fit, form and function needs.

We always aim to enhance customer satisfaction through improvement and assurance of conformity. At SLAYSON®, we look after you with the utmost care and expertise. Feel free to contact us today to discuss your location, application and requirements.