Technical measures to prevent electric shock

I. Direct Contact Electrical Protection Measures

Direct contact with electricity can lead to serious injuries or even death. To prevent this, several protective measures are implemented. First, insulation is used to cover live parts and prevent direct access. However, materials like paint or lacquer are not sufficient on their own for effective protection.

Second, barriers or fences are placed around electrical equipment to stop accidental contact. These also serve as a visual warning to people about the potential danger of touching live parts.

Third, obstacles are set up to prevent unintentional contact with live components. While they don't stop deliberate attempts, they help reduce the risk of accidental exposure.

Fourth, maintaining proper spacing ensures that live parts are out of reach. This is especially important when tools are being used, as the required distance should be increased in such cases.

Fifth, safety signs play a crucial role in alerting people to electrical hazards and promoting safe behavior around power sources.

Sixth, residual current devices (RCDs) or leakage protection systems are used as an additional safeguard. They quickly cut off power when a fault is detected, but should never be relied on as the sole protection method. Their operating current should be less than or equal to 30 mA.

Lastly, using a safe voltage level based on the working environment helps minimize the risk of electric shock. This is particularly important in areas where people may come into contact with electrical equipment regularly.

II. Indirect Contact Electrical Protection Measures

Indirect contact occurs when a person touches a conductive part that has become live due to a fault. To protect against this, several strategies are applied. One key measure is automatically disconnecting the power supply in case of a fault. This is achieved through automation components and proper wiring configurations, ensuring that the power is cut off within a safe time frame.

Another approach is to enhance insulation by using double-insulated or reinforced-insulated equipment. This prevents dangerous voltages from appearing on accessible parts if the main insulation fails.

Creating a non-conductive environment is another effective method. This involves insulating both the floor and walls so that no two points with different potentials are within 2 meters of each other, reducing the risk of electric shock during faults.

An equipotential environment connects all accessible conductive parts together, ensuring that no dangerous voltage difference exists between them. This significantly reduces the chance of electric shock.

Finally, electrical isolation using an isolation transformer or generator provides a separate, safer circuit. The isolated circuit must have a voltage below 500V and must not be connected to any other system to maintain its isolation properties.