The Crucial Role of Arc Flash Labels in the Context of Workplace Safety and Compliance
- Adam Brooks
- Oct 30, 2024
- 6 min read
Updated: May 14
Electrical hazard labels, commonly referred to as “arc flash labels” (even though these labels contain both arc flash information as well as shock/voltage information) are critical safety tools in electrical work environments. These labels provide essential information about potential electrical hazards and necessary safety precautions. Understanding how to read these labels correctly is crucial for anyone working with or around electrical equipment.
If you are a facility engineering manager, safety manager, or training manager, you will benefit from this in-depth look at each component of an arc flash label, the reasoning behind its design, and related best safety practices to protect your workforce from arc flash dangers.
Table of Contents
Arc Flash Label Layout
There is a lot of flexibility given by NFPA 70E regarding what an electrical hazard label can look like. It’s common that specific items are just simply listed on a label. We feel that the layout is just as important as the content. Below is an example of our preferred layout that meets all applicable standards:
All hazard labels must adhere to ANSI Z535 safety standards. Within that standard, Guidant Power has designed its labels to maximize safety through clear communication. The use of large text for critical information like incident energy and voltage allows for reading from a safe distance, avoiding wasted steps and reducing unnecessary exposure to potential hazards.
The separation of shock and flash hazard information improves clarity and reduces confusion, as these hazards often require different safety approaches. This logical separation helps workers quickly identify the relevant information for their specific task.
Simplicity is a key principle in the label design, following the philosophy that in electrical safety, simplicity equals safety. The goal is to enable quick understanding in potentially hazardous situations. Clear fonts, a limited color palette, and a logical information flow all contribute to reducing the risk of misinterpretation or overlooking crucial information.
More details regarding labeling requirements are discussed in this post: https://www.70econsultants.com/what-should-an-electrical-hazard-label-look-like/
Key Components of an Arc Flash Label
FLASH PROTECTION
Incident Energy
The incident energy value, typically displayed prominently on the label (e.g., 6.1 cal/cm²), represents the amount of thermal energy that could potentially be released during an arc flash event, calculated at the working distance (the working distance is typically 18” - the approximate length of a person’s arms, incident energy is based on this distance, remember the closer you get the higher the arc flash hazard). This value is crucial as it determines the severity of the potential arc flash and the level of Personal Protective Equipment (PPE) that must be worn by a qualified electrical worker who is interacting with that panel.
Measured in calories per square centimeter (cal/cm²), the incident energy level can range from less than 1.2 cal/cm² to over 100 cal/cm². 1.2 cal/cm2 represents the threshold amount of energy necessary to create a blister on skin. Higher values indicate the potential for a more severe burn. We prefer that the incident energy value be displayed in a large bold manner allowing workers to read it from a safe distance, enabling personnel to don appropriate PPE prior to working with the equipment. More information about arc flash hazards greater than 40 cal/cm^2 can be found here: https://www.70econsultants.com/blast-pressure-above-40-cal-cm2/
Arc Flash Boundary
Distance from exposed live parts where a person could receive a second-degree burn. If someone were to be in the area while work is being performed, they would need to stand this far away without any arc flash PPE.
SHOCK PROTECTION
Voltage
Alongside the incident energy level, you'll find the system voltage (e.g., 480V) displayed prominently. This information is vital for determining appropriate safety measures and approach boundaries. Common voltages you might encounter include 120V, 208V, 240V, 480V or higher for substations and utilities.
Higher voltages generally present greater hazards and require more stringent safety measures. The prominent display of both incident energy and voltage allows workers to quickly assess the potential dangers without needing to approach the equipment.
Shock Boundaries
The shock hazard section typically includes:
Limited Approach Boundary: The closest distance an unqualified person can approach
Restricted Approach Boundary: Distance requiring additional PPE and training
These boundaries are essential for defining safe working distances and PPE requirements. By clearly separating this information, the label helps workers quickly identify the relevant safety measures for their specific task. Remember to consider both arc flash boundary and the limited approach boundary when establishing safe distances for unqualified workers.
Required Personal Protective Equipment (PPE)
The label specifies the necessary protective gear for safe work. This may include arc-rated clothing with specific calorie ratings, face shields or flash suits, insulated gloves, and leather footwear.
Understanding and adhering to the PPE requirements is necessary to protect workers from both shock and arc flash hazards. The label's clear presentation of this information helps ensure that workers can quickly identify and don the appropriate protective gear before beginning work.
Understanding the Label
When approaching electrical equipment, always read the entire arc flash label before beginning work, even if you're familiar with the equipment. Conditions can change, and a thorough review ensures a comprehensive understanding of all hazards and requirements.
For arc flash protection, pay particular attention to the incident energy level, the PPE requirements for the energy directly relate to worker safety. Additionally, higher voltage requires higher rated shock protection. Always ensure that your available PPE matches or exceeds the label requirements.
Understanding the boundaries listed on the label is essential for establishing qualified worker safety and controlling access to unqualified workers.
What Workers Need to Know – Practical Application of Label Information
When approaching electrical equipment, the information on the arc flash label needs to be linked to practical safety measures. Here’s a common scenario:
Imagine the panel shows the following label information: • Incident Energy: 6.1 cal/cm² (at 18” working distance) • Voltage: 480V • Arc Flash Boundary: 54 inches
In this situation, you would need:
To maintain a distance of at least 54 inches (4’ 6”) unless wearing appropriate arc flash PPE.
Arc flash PPE would need to be rated higher than 6.1 cal/cm2
Arc-rated shirt and pants with a minimum arc rating of 6.1 cal/cm²
Arc-rated face shield and balaclava or arc flash suit hood, again rated to at least 6.1 cal/cm2
Rubber insulating gloves with protectors working inside the restricted approach boundary otherwise arc rated gloves (this includes heavy duty leather gloves).
Safety glasses or goggles
Hard hat
Hearing protection
Leather footwear
Be aware of the 480V system and its associated shock hazards
There could be 120V lighting in the door that your elbows could bump
You might only be working on a PLC but 480V could be nearby
This practical application demonstrates how the label's information directly informs your safety actions and equipment choices.
The Importance of Training
While arc flash labels provide crucial information, they are most effective when workers have received proper training in interpreting and applying this information. Regular training sessions should cover:
The physics of arc flash events and their potential consequences
Detailed explanation of each component on the arc flash label
Proper selection, use, and maintenance of PPE
Emergency procedures in case of an arc flash incident
Updates on any changes in standards or best practices
Training should be hands-on whenever possible, allowing workers to practice reading labels, selecting appropriate PPE, and setting up safe work boundaries.
Updating and Maintaining Labels
Arc flash labels are not static; they need to be updated whenever there are changes to the electrical system that could affect the incident energy calculations. Some key times to review and potentially update labels include:
After any modifications to the electrical system
When new equipment is installed
Following changes in operational procedures
As part of regular safety audits when labels are damaged or missing.
When periodic arc flash evaluation updates are performed (at intervals not to exceed 5 years).
Ensuring labels are up-to-date is crucial for maintaining a safe work environment. Outdated labels could provide inaccurate information, potentially putting workers at risk.
Beyond the Label: Comprehensive Electrical Safety
While arc flash labels are a critical component of electrical safety, they are part of a larger safety ecosystem. A comprehensive electrical safety program should also include:
Detailed lockout/tagout procedures
Regular equipment maintenance and inspection
A culture of safety that encourages reporting of potential hazards
Emergency response plans for electrical incidents
Ongoing education on electrical safety best practices
Organizations can create a more robust and effective electrical safety program by integrating arc flash label information with these broader safety practices.
Conclusion
Following the appropriate safety protocols around electrical hazards starts with proper understanding of arc flash label information. Ensuring labels are high visibility and easy to read, even from a distance, in the languages spoken by staff members, with all the necessary information will help workers prioritize safety and prevent injuries, including by wearing the appropriate type of PPE. To ensure correct and thorough labeling of all equipment, arc flash labels should be applied on site by the company providing the hazard analysis, rather than at a later date by non-specialized staff.
Ultimately, arc flash labeling is an integral part of a broader electrical safety strategy, which includes continuous training, adherence to protocols, and staying updated with standards like NFPA 70E and relevant OSHA guidelines.
