When extending your network into nontraditional or harsh environments—like manufacturing floors, warehouses, or outdoor facilities—your choice of enclosure can make or break the reliability of your equipment.
Choosing the right enclosure begins with understanding the standards and ratings that define how well it resists dust, water, corrosion, and environmental hazards. The right decision at the start can help you minimize downtime, avoid equipment damage, and reduce replacement costs.
Understanding Industrial Enclosure Ratings
Industrial enclosures are rated using several standards that define how much protection they provide from environmental hazards. The three most common are IP Codes, NEMA Ratings, and UL Type Ratings. Each system plays a key role in ensuring your equipment is housed safely—whether indoors, outdoors, or in demanding industrial environments.
What Are IP Codes?
The International Electrotechnical Commission (IEC) standard 60529, also known as the Ingress Protection (IP) Code, classifies the level of protection an enclosure provides against solids and liquids.
An IP rating includes two digits—for example, IP55:
- The first digit indicates protection against solid objects like dust.
- The second digit indicates protection against liquids.
For example, IP66 provides complete protection against dust and high-pressure water jets, making it suitable for washdown or outdoor environments.
The higher the number, the greater the protection. However, IP ratings do not measure corrosion resistance, which is covered by NEMA and UL standards.
NEMA vs. UL Enclosures: Key Differences You Need to Know
In North America, the National Electrical Manufacturers Association (NEMA) publishes NEMA Standard 250 Enclosures for Electrical Equipment (1,000 V Maximum), which identifies 16 types of enclosures for nonhazardous locations, each providing a different level of protection against dust and liquid penetration.
Underwriters Laboratory (UL) has a similar system in UL 50 Enclosures for Electrical Equipment, Non-Environmental Considerations; UL 50E Enclosures for Electrical Equipment, Environmental Considerations; and UL 508A Standard for Industrial Control Panels.
NEMA Enclosures
The NEMA Standard 250 defines 16 enclosure types for nonhazardous locations, each offering specific protection against dust, dirt, oil, water, and corrosion. NEMA ratings indicate how well an enclosure safeguards equipment from environmental conditions such as moisture, particulates, and accidental contact.
UL Enclosures
UL Standards 50, 50E, and 508A establish performance and safety testing for enclosures:
- UL 50 – Non-environmental construction considerations
- UL 50E – Environmental performance requirements
- UL 508A – Standards for industrial control panels
The main distinction between the two systems lies in certification:
- NEMA enclosures are typically self-certified by the manufacturer.
- UL Type enclosures undergo third-party testing and certification by UL to confirm verified performance and compliance.
Common Ratings for Nonhazardous Environments
Most indoor and outdoor nonhazardous environments can be protected using one of three common rating types. These represent the most widely used industrial enclosure ratings for IT, automation, and control applications.
IP / NEMA Rating | Typical Type | Protection Level | Common Uses |
|---|---|---|---|
IP54 / NEMA 12 | Indoor | Dust- and drip-resistant | Factory floors, indoor control panels |
IP66 / NEMA 4 | Indoor/Outdoor | Dust-tight and water-resistant | Washdown areas, outdoor installations |
NEMA 4X | Indoor/Outdoor | Dust-tight, water-resistant, corrosion-resistant | Food processing, coastal or chemical environments |
These enclosures can also be customized with vents, fans, or air conditioners to meet specific thermal or environmental requirements.
Choosing the Right Enclosure Style
Once you’ve identified the required protection level, the next step is choosing the style and size that fits your equipment and installation needs.
There are four basic styles of industrial enclosures:
1. Modular Enclosures
are most like IT equipment cabinets.
- Frame includes hinged doors and bolt-on side panels, top panel and bottom panel
- Leveling feet support the frame or a plinth attaches the frame to the floor
- Removable panels allow you to create bays of multiple enclosures to hold larger arrays of equipment, and the frames have a multitude of mounting locations for rails, panels, and accessories
- Can be fitted with an assortment of 19" EIA mounting rails for IT equipment or panels for automation electronics
- Typically have very high load ratings and wide range of accessories for both IT and automation application
2. Free-Standing Enclosures
are simpler designs, formed as single monolithic enclosures in specific sizes used as stand-alone enclosures.
- Single door or front and rear doors
- Support panels for mounting automation, controls, or instrumentation electronics
- Specific size enclosures may include 19" EIA mounting rails for IT equipment
3. Floor-Mount Enclosures
are like free-standing enclosures formed as single monolithic enclosures in specific sizes used as standalone enclosures.
- Elevated above the finished floor adding clearance and easier cable access
- Typically wider with double doors
- Have a large panel for mounting automation electronics, controls and instrumentation
- Do not include 19" EIA mounting rails for IT equipment.
4. Wall-Mount Enclosures
Wall-mount enclosures attach to the wall, support smaller amounts of equipment, and come in two basic styles:
- Swing-out style is hinged at the rear so you can access the back of equipment. This style can be fitted with 19" EIA mounting rails for IT equipment or panels for automation electronics
- Fixed style has front-only access, and may also feature both 19" EIA mounting rails and panels or just panels
How to Size and Fit Your Enclosure
Proper sizing ensures your equipment operates efficiently and safely:
- 19” EIA rails: For rack-mounted IT or network equipment.
- Panel mount: For automation or control equipment.
Ensure extra clearance for cable routing, ventilation, and door swing.
Always allow clearance for cables, ventilation, and door swing to simplify service access.
Finding the Right Solution
Chatsworth Products’ RMR® Industrial Enclosures are engineered to perform in the most demanding conditions—providing industry-leading protection from dust, water, and corrosion. Each enclosure is designed and tested to meet strict NEMA, UL, and IP standards for long-term reliability.
or to see ratings, styles, and configurations for any environment.
