Electrical Safety: Paramount Principles and Practices

6.1 Hazards of Electricity: Understanding the dangers is the first step towards prevention.

1. Electric Shock:

Mechanism: Occurs when a person becomes part of an active electrical circuit, allowing current to flow through their body. This happens when two points of different electrical potential are simultaneously touched (e.g., live wire and ground, or live and neutral).

Severity Factors: The harmfulness of an electric shock depends critically on:
- Magnitude of Current: Even small currents (e.g., 1 mA for perception, 10-20 mA for muscle contractions preventing release, 50 mA for ventricular fibrillation – a fatal heart rhythm disturbance, 100-200 mA for ventricular fibrillation leading to death) can be lethal.
- Path of Current: Current passing through vital organs (e.g., heart, lungs, brain) is far more dangerous. Hand-to-foot current path is particularly hazardous.
- Duration of Contact: Longer exposure increases the risk of severe injury or fatality.
- Frequency: AC current (especially 50-60 Hz) is generally more dangerous than DC current at the same magnitude due to its tendency to cause muscle contraction (cannot let go) and ventricular fibrillation.
- Body Resistance: Skin resistance varies with moisture. Wet skin offers lower resistance, making shocks more dangerous.

Effects: Ranges from tingling sensations, muscle spasms, and localized burns to respiratory arrest, cardiac arrest, internal organ damage, and death.

2. Electrical Fire:

Mechanism: Occurs when electrical energy is converted into excessive heat, igniting combustible materials.

Common Causes:
- Overloaded Circuits: Drawing more current than the wire's or protective device's rating. Wires overheat, insulation melts, and sparks can ignite nearby materials.
- Short Circuits: An unintended low-resistance path between live conductors or live-to-earth, resulting in extremely high fault currents and rapid, intense heat generation.
- Faulty Wiring/Degraded Insulation: Old, cracked, or damaged insulation can lead to arcing, intermittent sparking, and localized heating at defect points.
- Loose Connections: High resistance at loose terminals causes localized heating (due to I2R losses), which can escalate to fire.
- Improper Equipment Use: Using damaged appliances, incorrect extension cords, covering vents on equipment, or using equipment in wet environments not rated for it.

• Arc Flash: A sudden, catastrophic electrical discharge through the air, releasing immense energy in the form of intense heat, light, and pressure waves. Can cause severe third-degree burns, ignite clothing, and propel molten metal.

6.2 Basic Safety Rules and Precautions: Adherence to these fundamental rules is non-negotiable for anyone working with or around electricity.

1. ALWAYS Assume Circuits Are Live: Never assume a circuit is de-energized. Always verify zero voltage using a properly rated and tested voltage tester before touching any conductors.
2. Disconnect Power and Implement Lockout/Tagout: Before commencing any work on an electrical circuit or equipment, completely de-energize the circuit at its source (e.g., switchboard). Then, apply Lockout/Tagout (LOTO) procedures: physically lock the disconnecting means in the OFF position and place a tag indicating that work is in progress and the circuit must not be re-energized. This prevents accidental re-energization.
3. Use Appropriate Personal Protective Equipment (PPE): Depending on the task and voltage level, wear insulated gloves, safety glasses or face shields, flame-resistant (FR) clothing, hard hats, and insulated footwear. Use only insulated tools that are specifically rated for the voltage of the circuit being worked on.
4. Never Work Alone on Live Circuits: A buddy system ensures that in case of an emergency (e.g., electric shock), there is someone present to provide immediate assistance or call for help.
5. Use the Right Tools and Equipment: Ensure all tools are in good working condition, properly insulated, and suitable for the task at hand. Avoid makeshift tools.
6. Do Not Bypass Safety Devices: Fuses, circuit breakers, and RCDs are life-saving devices. Never replace a blown fuse with one of a higher rating or with a makeshift conductor (e.g., coin, wire). Never hold or jam circuit breakers in the ON position.
7. Regularly Inspect Cords and Equipment: Before each use, visually inspect power cords, plugs, and equipment for damage (frayed wires, exposed conductors, cracked insulation). Immediately repair or replace any damaged items.
8. Keep Work Areas Dry and Clear: Avoid working with electricity in wet or damp conditions. Water is conductive and increases shock risk. Ensure the work area is clean, well-lit, and free of clutter to prevent trips and falls.
9. Ensure Proper Earthing (Grounding): Verify that all metallic enclosures of electrical equipment, panels, and appliances are correctly and effectively earthed. The earth connection must be low resistance and continuous.
10. Avoid Overloading Circuits: Do not plug too many appliances into a single outlet or extension cord. This can draw excessive current, overheat wiring, and lead to fire.
11. Proper Wiring Practices: All electrical wiring and installations must be carried out by qualified and licensed electricians, strictly adhering to national and local electrical codes and standards.
12. Maintain Safe Clearances: Be aware of and maintain minimum safe distances from exposed live electrical conductors, overhead power lines, and electrical equipment, especially when operating machinery or handling long objects.

6.3 First Aid for Electric Shock (Brief and Immediate Steps):

• The absolute first priority is to ensure the safety of the rescuer. Do NOT touch the victim if they are still in contact with the electrical source, as you risk becoming a victim yourself.
• Disconnect the Power Source Immediately: If possible and safe to do so, turn off the main circuit breaker, pull the plug, or switch off the appliance's power. This is the fastest and safest way to separate the victim from the electricity.
• Separate the Victim from the Source (Only if Power Cannot Be Turned Off Safely): If you cannot immediately turn off the power, use a non-conductive object (such as a dry wooden stick, a plastic pipe, a thick folded newspaper, a rubber mat, or a thick rope) to push or pull the victim away from the electrical source or to push the live wire away from the victim. Never use anything wet or metallic.
• Call for Emergency Medical Help: Immediately call your local emergency services (e.g., 911 or 108 in India). Even if the person seems fine, electric shock can cause internal damage or delayed cardiac issues.
• Check for Breathing and Pulse: Once the victim is safely separated from the electrical source, assess their condition.
• If the person is not breathing and/or has no pulse, begin Cardiopulmonary Resuscitation (CPR) immediately if you are trained. Continue CPR until emergency medical personnel arrive.
• If the person is breathing and has a pulse, keep them still and comfortable.
• Treat for Burns: If there are visible burns, cover them loosely with a clean, dry, non-fluffy dressing or sterile gauze. Do not apply ointments or break blisters.
• Keep the Person Warm and Calm: Lay the person down and cover them with a blanket to prevent shock. Reassure them and keep them as calm as possible until medical help arrives.
• Do NOT:
• Touch the victim if they are still connected to the power source.
• Use water to try and extinguish an electrical fire (use a CO2 or dry chemical extinguisher, or sand).
• Attempt to move the victim unless absolutely necessary (e.g., to perform CPR) or if there's immediate danger.
• Give the victim anything to eat or drink.