Arc Flash Labels: NFPA 70E Requirements for Electrical Equipment

You’re standing in front of an electrical panel that needs servicing. Before the enclosure is opened, you need to understand the potential arc-flash hazard and what protective measures may be required.

That information shouldn’t be buried in a report somewhere. It needs to be available where your team encounters the equipment.

That’s the purpose of an arc-flash label. 

It communicates critical hazard information before a qualified person begins examination, adjustment, servicing, or maintenance.

But what equipment actually needs a label? What information belongs on it? Where should it be placed? And how do the requirements differ between the United States and Canada?

Before getting into the labels themselves, it’s important to distinguish between NFPA 70E, OSHA requirements, and CSA Z462. They overlap in their goal of protecting your workers from electrical hazards, but they aren’t interchangeable.

NFPA 70E and OSHA in the US

In the United States, the 2024 edition of NFPA 70E, Standard for Electrical Safety in the Workplace, provides detailed requirements and guidance for protecting workers from electrical hazards, including shock and arc flash. It covers electrical safety-related work practices, arc-flash risk assessments, PPE, and equipment labelling.

OSHA, meanwhile, establishes legally enforceable workplace safety requirements in the United States. Its electrical standards address hazards including shock, electrocution, fire, explosions, and electrical arcs. However, OSHA does not contain the same specific arc-flash equipment-labelling provision found in NFPA 70E. OSHA has stated that its electrical provisions require safety signs, symbols, or accident-prevention tags where necessary to warn employees about electrical hazards that could endanger them.

CSA Z462:24 in Canada

For Canadian facilities, the key consensus standard is CSA Z462:24, Workplace electrical safety. Like NFPA 70E, CSA Z462 addresses workplace electrical hazards, including shock and arc flash, and provides a framework for hazard assessment, safe work practices, PPE, and risk reduction.

The two standards are closely aligned in many areas, but they are not identical or automatically interchangeable. Canadian employers must follow the federal, provincial, or territorial occupational health and safety requirements applicable to their jurisdiction, while CSA Z462 provides an important framework for managing workplace electrical safety.

Under NFPA 70E Section 130.5(H), certain electrical equipment must be field-marked with a label when it is likely to require examination, adjustment, servicing, or maintenance while energized.

The equipment categories specified include:

• Switchboards 
• Panelboards 
• Industrial control panels 
• Meter socket enclosures 
• Motor control centres 

The requirement applies when this equipment is in other than dwelling units and is likely to require energized interaction.

From a practical standpoint, pay particular attention to equipment your team may need to open, test, troubleshoot, adjust, inspect, or maintain while energized.

It’s important to note that this doesn’t preclude arc-flash labels from other equipment, such as switchgear and certain disconnects. As the facility or safety manager, you may decide to do this as part of your broader safety program.

Under NFPA 70E, the label for equipment covered by Section 130.5(H) must include specific information to help qualified persons understand the hazard before interacting with the equipment.

The required information includes the following.

1. Nominal System Voltage

This gives workers immediate information about the electrical system they’re approaching and supports the planning of electrical safety-related work.

2. Arc-Flash Boundary

This is the distance at which the incident energy equals the threshold associated with the onset of a second-degree burn.

In practical terms, it helps define how close a person can approach an arc-flash hazard without appropriate protection.

3. Incident Energy or PPE Information

The label must also include at least one of the permitted forms of PPE or incident-energy information.

Depending on the method used, this may include:

• Available incident energy and the corresponding working distance 
• Minimum arc rating of clothing 
• Site-specific PPE level 
• Arc-flash PPE category, where the category method is used 

One common misconception is that every arc-flash label must show both incident energy and a PPE category. That’s not necessarily the case. The information displayed depends on the assessment method used and the requirements of the standard.

4. What Else Might Appear on an Arc-Flash Label?

The three above are the minimum under NFPA 70E. But you may also see other information as per site-specific safety programs and maintenance practices; Things like: equipment identifier, shock hazard information, restricted approach boundary, study date, label revision date, and equipment location.

The label should be positioned so that qualified persons can see and read the hazard information before beginning examination, adjustment, servicing, or maintenance.

Here’s what that means for common electrical equipment:

• Panelboards and switchboards: Place the label on the exterior of the enclosure where it can be read before the door or cover is opened. 
• Motor control centres: Position the label where technicians can identify the hazard before accessing the relevant energized compartment. 
• Industrial control panels: Install labels where handles, open doors, conduit, adjacent equipment, or other obstructions won’t block them. 
• Meter socket enclosures: Place labels on a clearly visible exterior surface where workers can review the hazard information before accessing the enclosure. 
• Outdoor electrical equipment: Choose a location that remains visible while minimizing unnecessary exposure to standing water, abrasion, direct impact, and accumulated dirt where practical. 

You should also consider how the equipment is actually used. A label that looks perfectly positioned when the equipment is closed may become hidden behind a door or panel when maintenance begins.

Under NFPA 70E, arc-flash labels must be durable enough for the environment in which they’re installed. The standard doesn’t prescribe one specific label material for every application. Instead, the label needs to remain suitable for the conditions it will actually face. 

That means your material choice should be based on factors such as UV exposure, moisture, chemicals, abrasion, temperature, and the expected service life of the equipment. Here’s how that translates into practical material choices.

1. Indoor Electrical Rooms and Controlled Environments

For electrical panels, switchboards, and control equipment installed indoors, labels are generally protected from direct weather exposure but may still encounter dust, routine cleaning, handling, and occasional abrasion.

Suitable options include:

• Laminated vinyl decals, which provide a practical solution for displaying detailed arc-flash information. 
• Lamacoid labels, which provide rigid, engraved identification and are well suited to permanent equipment IDs and electrical-panel identification in controlled indoor environments. 

A laminated decal is a more practical choice in most cases, because these arc-flash labels commonly need colour, detailed hazard information, and multiple data fields.

2. Outdoor Electrical Equipment

Outdoor switchboards, panelboards, meter enclosures, and other electrical equipment may be exposed to UV radiation, rain, snow, moisture, temperature swings, and freeze-thaw cycles.

Suitable options include:

• UV-resistant laminated vinyl decals designed specifically for outdoor exposure 
• MetalPhoto nameplates, which offer excellent resistance to UV exposure, weather, abrasion, and demanding outdoor conditions 
• Anodized aluminum nameplates for durable equipment identification where a rigid metal plate is appropriate 

An arc-flash label often contains colour-coded warnings and hazard-specific information. A metal plate offers excellent durability, but the selected marking method still needs to reproduce the required information clearly. 

For many outdoor applications, a high-performance laminated decal specifically rated for outdoor use may be the better fit.

3. Harsh Industrial Environments

In manufacturing plants, processing facilities, and other demanding industrial environments, labels may face oils, grease, chemicals, solvents, washdowns, abrasion, and repeated cleaning.

Suitable options include:

• Chemical-resistant laminated decals for applications where detailed, full-colour hazard information is required 
• MetalPhoto nameplates for demanding environments requiring excellent resistance to chemicals, abrasion, moisture, and long-term exposure 
• Etched stainless steel nameplates for particularly severe environments involving corrosion, physical wear, or aggressive cleaning 

The specific chemical exposure matters. A material that performs well around oils and mild cleaners may not withstand strong solvents, acids, or caustic chemicals. Before specifying a label, identify the substances it may contact and verify that the face material, printed image, laminate, and adhesive are compatible.

4. High-Temperature Areas

Electrical equipment near furnaces, turbines, engines, boilers, or high-temperature process equipment creates a different challenge.

You need to consider both:

• Ambient temperature around the equipment 
• Actual surface temperature where the label will be installed 

Suitable materials include:

• Etched stainless steel, which can provide durable identification in high-temperature and severe industrial environments 
• MetalPhoto, where temperatures remain within the material’s rated performance range 
• Specialty high-temperature labels, where the complete construction is rated for the actual exposure 

This is one area where you shouldn’t choose a material based on general categories alone. The actual operating temperature matters, especially for adhesive-mounted labels, since the adhesive may fail before the face material does.

Electrical systems don’t remain static. Equipment gets replaced, protective-device settings change, transformers are upgraded, and system configurations evolve.

That’s why NFPA 70E requires the arc-flash risk assessment to be reviewed periodically, at intervals not exceeding five years. It must also be updated when a major modification or renovation takes place that could affect the assessment.

Major modification or renovation in this instance means: 

• Electrical distribution equipment is added or replaced 
• Transformers are changed 
• Protective-device settings are modified 
• Available fault current changes 
• Utility information changes 
• System configurations are modified 
• An updated study changes the calculated incident energy or arc-flash boundaries 
• Equipment is relocated or repurposed 

Keep in mind that the five-year assessment review interval doesn’t necessarily mean every arc-flash label must automatically be replaced every five years.

It’s also good practice to include arc-flash labels in routine electrical inspections. Don’t wait for the next formal assessment to discover that a label has peeled away or become unreadable.

An arc-flash label can only do its job if the information on it is accurate, it’s placed where workers can see it, and it remains readable in the environment where it’s installed.

Whether your facility follows NFPA 70E in the United States or uses CSA Z462 as part of its electrical safety framework in Canada, arc-flash labelling should make sure it does its job of giving workers clear hazard information before work begins.

At Industrial Nameplates, we manufacture durable custom labels and metal nameplates for electrical and industrial environments. 

If you need arc-flash labels designed to remain clear and readable under demanding operating conditions, give us a call at 403-930-5543, email sales@industrialnameplates.ca, or contact us to discuss your application.