Unidad 3. Vídeo 2. Flipped FOL. Riesgo eléctrico

Understanding Electrical Safety Risks

Types of Electrical Contact

• Direct Contact: Occurs when a worker experiences an electric shock by touching live parts, such as wires in a plug.

• Indirect Contact: Happens when someone touches a non-active part that becomes energized, like the casing of a washing machine.

• High Voltage Contact: Involves installations over 1,000 volts where an electrical arc can occur, leading to sudden energy release.

Factors Influencing Electric Shock Severity

Key Determinants

• Voltage (Tension): The potential difference between two points measured in volts; high voltage is considered above 1,000 volts.

• Resistance: The opposition to current flow measured in ohms; varies based on contact surface area and environmental conditions.

• Current Intensity: Measured in amperes; relates voltage and resistance. It indicates how much current flows through the body during contact.

Effects of Current Intensity

• A range from 1 to 3 milliamperes causes tingling sensations.

• Between 10 to 25 milliamperes leads to muscle contraction making it hard to let go of the source.

• At higher levels (30 to 80 milliamperes), serious conditions like ventricular fibrillation or respiratory arrest may occur.

Pathway and Duration of Electric Shock

Importance of Current Pathway

• The path taken by electricity through the body determines injury severity; critical organs include lungs and heart.

Impact of Exposure Time

• Longer exposure increases damage risk; for instance, half a second at 500 milliamperes can lead to ventricular fibrillation with a probability of 50%.

Prevention Measures Against Electric Shocks

Direct Contact Protection Strategies

• Keep active parts away from workers using barriers or insulation materials. Use safety voltages below 25 volts where possible.

Indirect Contact Protection Strategies

• Install grounding systems on machines which redirect stray currents safely into the ground if contact occurs.

Safety Measures to Prevent Electrical Hazards

Key Strategies for Worker Protection

• Separation of Circuits: Utilizing transformers to separate circuits is a crucial measure in preventing electrical hazards, ensuring that different electrical systems do not interfere with each other.

• Grounding Installations: The installation of grounding systems is essential for protecting workers from electric shocks, providing a safe path for excess electricity.

• Signage and Information: Proper signage should be used to inform workers about potential electrical hazards, enhancing awareness and safety protocols on-site.

• Personal Protective Equipment (PPE): Workers should utilize appropriate PPE such as insulated gloves and poles designed specifically for electrical work to minimize the risk of injury during operations.