Arc Flash Study and Why They are Needed

What is a flash of arc?

The sudden release of energy caused by an accidental arc fault (short circuit) between live parts or between live parts and ground is known as an arc flash. A concussive pressure wave that may carry shrapnel is produced when heat and light clash (an electrical explosion), releasing the energy. Cal/cm2, also known as incident energy, is a unit of measurement for the resulting energy.

An arc flash study is what?

According to NFPA 70E:

Standard for Electrical Safety in the Workplace, an arc flash study, also known as an arc flash hazard analysis or arc flash risk assessment, is a study that identifies arc flash hazards, estimates the likelihood of severe injury, and assists in determining the additional protections (controls and personal protective equipment (PPE)) required for a given electrical system/installation. Simply put, an arc flash study helps determine safe approach distances and personal protective equipment (PPE) for performing maintenance work by providing information regarding the incident energy available at the electrical components/devices that personnel would be exposed to while maintaining or otherwise interacting with that equipment.

Why is a study of arc flash necessary?

To determine the greatest amount of energy that equipment in need of maintenance might discharge, an arc flash analysis is necessary. An arc flash study can also instruct a designer on how to get rid of or lower the danger of a hazard. Without an arc flash analysis, it is impossible to determine the best methods for protection, mitigation, elimination, and reduction in order to provide a secure working environment near electrical installations and equipment.

What Situations Call for an Arc Flash Study?

Several laws emphasizing the need to create a safe working environment for the staff servicing equipment have resulted in arc flash research. Occupational Safety and Health Administration (OSHA), NFPA 70E, National Electrical Code (NFPA 70), and Institute of Electronics and Electrical Engineers standards are the foundation for the requirement (IEEE). Moreover, certain states, notably Washington (WAC296-45-325), have laws requiring the performance of arc flash hazard analyses.

OSHA mandates health and safety standards for companies, as you may know. OSHA based its electrical safety regulations on the data supplied in NFPA 70E. (CFR 29 Part 1910 and Part 1926). According to CFR Part 1910.132, employers are expected to determine if workplace hazards are present or likely to be present and to safeguard their employees from such risks.

Every piece of electrical machinery and installation has some amount of danger, especially when it’s possible to repair or use it while it’s electrified. This can refer to the use of enclosed circuit breakers, testing, troubleshooting, and any contact with active parts when doing maintenance. In accordance with CFR Part 1910.132, the employer must also formally certify that the necessary danger assessment has been carried out. Knowing this makes it easier for you to recognize the risks that might be present in any electrical system. These dangers must be recognized and labeled in accordance with OSHA 1910.132 so that the appropriate PPE may be chosen. Herein lies the role of NFPA 70E.

The obligations for employers with relation to electrical safety are outlined in Section 110.1 of NFPA 70E, “Standard for Electrical Safety in the Workplace.” The employer must “create and record an overall electrical safety program that directs activities suitable to the risk of electrical hazards,” according to the requirement. If an organization has an overall occupational health and safety management system, it must integrate the electrical safety program into it.

Information on shock and arc flash hazard concerns is provided in Section 130.5, together with guidelines for detecting and calculating the dangers of each. The incident energy at the necessary working distance, sometimes referred to as the arc flash boundary, as well as the appropriate amount of personal protective equipment (PPE) that must be employed inside the arc flash boundary, must be determined by doing an arc flash analysis. All equipment that is “likely to require examination, adjustment, servicing, or maintenance while energized…” must also be labeled, according to Section 130.5. The label must include the following information, among other requirements: arc flash risk identification, risk severity, arc flash boundary, and necessary PPE.

What is Need to Complete an Arc Flash Study Correctly?

Arc flash studies may be carried out using a variety of applications, however the information needed is fairly specific. Having a precise and thorough depiction of the electrical infrastructure to be studied is essential for carrying out an arc flash analysis. The current as-built one-line paperwork often contains the bulk of this information; nevertheless, field verification of conductor lengths should be done to verify the study accurately reflects the as-built circumstances. A field inspection of the installation is necessary if the current documentation is either unavailable or insufficient. For the purpose of creating an accurate model, the following data is required:

Practical information
running voltage
present fault current
Utilities safety gear at the servicing location
Information from paralleled sources, such as those that use many services, generators, or other backup power sources.
data on electrical equipment
Manufacturer
Types
Sizes
current settings for time
Rating for short-circuit interrupting
Type, size, and lengths of cables and conductors
linked to the system motors
rating in horsepower
Configuration of NEMA
Transformer
Rating
Impedance readings
tap options
Approach to Henderson’s Arc Flash Mitigation
Taking steps to reduce the likelihood that an issue may arise is always the wisest course of action. Henderson Engineering has created a tried-and-true method for arc flash risk mitigation, which lowers the possibility of harm for building occupants.

De-energizing the apparatus is the initial stage in the procedure. This is the simplest method for removing the arc flash threat. Also, this procedure entails carrying out lock-out and tag-out procedures. De-energizing the equipment, however, is not always an option due to factors like life safety concerns, mission-critical usage, or expenses associated with downtime. In these situations, it is necessary to use our highly qualified field employees who can collect data while equipment is powered up in a way that safeguards both human safety and the integrity of the electrical systems.

Using remote work is another method of mitigation. Circuit breakers (CBs), switchgear, and remote sensor addition all fall within this category. Remote labor increases the arc flash boundary’s natural distance, further enhancing worker safety.

Protecting employees against arc flash can be accomplished in large part using practical safety precautions. It is usually advised to use suitable (PPE) based on calculations. Planning and training are crucial. Helping owners comprehend the expense of arc flash mitigation is frequently quite beneficial and directly related to safety. Stakeholders can take control of their own safety by being informed about effective mitigation procedures by staff and building owners.