An Introduction to Risk Assessment

Arc flash incidents are among the most severe hazards in electrical installations, with potentially catastrophic consequences for people, equipment, and infrastructure. This series aims to deepen your understanding of arc flash phenomena, provide a systematic knowledge framework, and guide you through the essentials of a thorough risk assessment in this domain. Let’s begin!

The Essentials of Arc Flash Risk Assessment

Performing a proper Arc Flash Risk Assessment requires precise calculations and adherence to established guidelines. Depending on the region, these include:

• IEEE 1584 – Guide for Performing Arc-Flash Hazard Calculations (global),
• NFPA 70E – Handbook for Electrical Safety in the Workplace,
• DGUV 203-077 – (Germany),
• Experimental methods and engineering best practices.

This article outlines a comprehensive process to help you understand what goes into a detailed and professional assessment.

How Does a Typical Risk Assessment Project Work?

The following steps for a typical project give us an idea of what we should expect. Of course, the requirements can be expanded depending on the particular installation or specific customer requirements.

The standard IEEE 1584.1 outlines the necessary components of an arc flash risk assessment report and specifies mandatory documentation. A superficial analysis that merely provides a table of results, without actionable insights, is of little value. Below is a structured, 16-step process to ensure a reliable and actionable outcome.

The 16-Step Process

1. Define the Scope of Work – Collaborate with the client to establish the scope, typically covering everything from the connection point to overcurrent protection rated at 63A in a 400V network.
2. Data Collection – Conduct on-site inspections and review electrical documentation, network schematics, and operating descriptions.
3. Model Creation – Develop a model of the electrical installation using advanced software (e.g., SKM, ETAP, CYME, Easypower).
4. Short-Circuit Current Analysis – Perform calculations based on standards (IEC 60909, ANSI, IEC 61660, etc.) for various operational scenarios.
5. Selectivity Analysis (Current State) – Prepare protection device characteristics and documentation.
6. Equipment Short-Circuit Rating Assessment – Verify the durability of switchgear and breakers against calculated short-circuit currents.
7. Arc Flash Analysis (Current State) – Calculate arc flash incident energy and determine PPE requirements for all switchgear under the current setup.
8. Results Review – Identify recommendations to improve selectivity, reduce arc flash energy, or highlight equipment that exceeds its short-circuit capacity.
9. Selectivity Analysis (Recommendations) – Propose adjustments to protection device settings and medium-voltage (MV) protections to enhance selectivity.
10. Arc Flash Analysis (Recommendations) – Recalculate based on proposed settings or technical solutions.
11. Reporting – Compile all results, recommendations, modeling data, single-line diagrams, and informational labels in formats like PDF or Excel.
12. Training – Provide introductory training on arc flash risks, either on-site or via teleconference.
13. System Labeling – Supply and install informational labels on analyzed switchgear.
14. PPE Selection – Assist in selecting appropriate Personal Protective Equipment (PPE).
15. Report Presentation – Discuss the report findings and technical solutions with the client.
16. Updates – Regularly update results every five years or after significant system upgrades.

Why a Thorough Analysis Matters

Superficial assessments may offer quick results, but often leave clients with insufficient insights and unresolved risks. A comprehensive analysis, supported by actionable recommendations and system improvements, ensures both safety and efficiency.

In the following articles, we’ll dive deeper into each phase of the process, offering practical solutions to enhance electrical safety and mitigate arc flash risks.