FAQs about electric arc suit?

1.What is arc flash?

Arc flash is an electrical explosion caused by low impedance grounding or another phase in the electrical system. High temperature will cause rapid heating and extreme pressure of the surrounding air, resulting in arc explosion. Arc explosion (the result of arc flash) may evaporate all solid copper conductors. When evaporated, the solid copper conductor will expand to 67000 times its original volume.

Arc explosion releases flame, strong light and pressure wave, forming flying shrapnel explosion. Arc flash occurs without warning. This usually causes complete destruction of the equipment involved and serious injury or death within the arc flash boundary in the event of an accident.

The energy released by the arc flash is a function of the system voltage, the available fault current at that location, and the arc duration.

2.Aware of the arc flash hazards on low voltage equipment

The theory that arc flash hazards are greater at higher voltages is a common misconception. For low voltage (e.g. 480v), due to the higher fault current, it is more common to have a higher risk level of arc flash. Most the recorded arc flash accidents occur at lower voltages because the faults are caused by technicians working on electrical equipment. Due to the long clearing time and high fault current of the protection device, it is not uncommon for Category 3 or category 4 arc flash hazard to occur on low-voltage systems.

3.What causes arc flash?

When a large amount of fault current flows through multiple conductors, the potential difference will ionize the air, forming a low resistance path between the conductors. There are some events which can make arc flash more prone, such as incorrect tools, incorrect electrical equipment, corrosion of electrical equipment, incorrect working technology, lack of electrical safety training and lack of preventive maintenance etc.

4.What kind of damage will arc flash cause?

It is estimated that 5 to 10 arc flashes and explosions occur in electrical equipment, and 2000 people enter burn centers due to severe burnsevery day in the United States. 

The degree of injury is directly related to the power of the arc flash, the distance of personnel during the arc flash, and the protective equipment (PPE) individuals wear during the arc flash.

Burns, concussion, lung failure, hearing loss, shrapnel injury and fractures are common injuries due to the power of energy explosion and high heat.

5.What are the costs associated with arc flash accidents?

The total cost of an arc flash accident is estimated to be between $12 million and $15 million, including expenses, downtime, equipment replacement, litigation, and insurance and litigation costs.

6.How to determine the correct level of PPE?

In order to select the appropriate PPE (personal protective equipment), it is necessary to understand the incident energy at each point where workers may need to work on energized equipment. These calculations are determined in the arc flash study and need to be performed by qualified personnel, such as electrical engineers.

Based on the above, Shanghai C&G suggests that you choose arc protection equipment in combination with the actual situation to avoid the risk of personal injury.