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BASIC ELECTRICAL SAFETYHAZARDS OF ELECTRICITYThe primary hazards associated with electricity and its use are:1-SHOCKElectric shock occurs when the human body becomes a part of a path through which electrons can flow. The resulting effect on the body can be either direct or indirectDirect Injury or death can occur whenever electric current flows through the human body. Currents of less than 30 mA can result in death. IndirectAlthough the electric current through the human body may be well below the values required to cause noticeable injury, human reaction can result in falls from ladders or scaffolds, or movement into operating machinery. Such reaction can result in serious injury or death.2 BURNSBurns can result when a person touches electrical wiring or equipment that is improperly used or maintained. Typically, such burn injuries occur on the hands.3- ARC-BLASTArc-blasts occur from high-amperage currents arcing through air.This abnormal current flow (arc-blast) is initiated by contact between two energized points. This contact can be caused by persons who have an accident while working on energized components, or by equipment failure due to fatigue or abuse.Temperatures as high as 35,000F have been recorded in arc-blast research. 4-EXPLOSIONSExplosions occur when electricity provides a source of ignition for an explosive mixture in the atmosphere. Ignition can be due to overheated conductors or equipment, or normal arcing (sparking) at switch contacts.5- FIRESElectricity is one of the most common causes of fire both in the home and workplace. Defective or misused electrical equipment is a major cause, with high resistance connections being one of the primary sources of ignition. High resistance connections occur where wires are improperly spliced or connected to other components such as receptacle outlets and switchesHeat is developed in an electrical conductor by the flow of current at the rate I2R. The heat thus released elevates the temperature of the conductor material. A typical use of this formula illustrates a common electrical hazard. If there is a bad connection at a receptacle, resulting in a resistance of 2 ohms, and a current of 10 amperes flows through that resistance, the rate of heat produced (W) would be

If you have ever touched an energized 200 watt light bulb, you will realize that this is a lot of heat to be concentrated in the confined space of a receptacle. Situations similar to this can contribute to electrical fires.BASIC ELECTRICAL SAFETY

Electricity is potentially lethal. It must be treated with respect at all times and used only in approved ways. Hundreds of people every year die as a result of the misuse of electricity. They die as a direct result of electric shock, or as an indirect result of faulty or misused electrical equipment that causes fire.Listed below are some important points to remember when working with electricity.1 Never work on live equipment (unless a special live test is required, for which you will need to be an experienced and competent person).2 Always ensure, by using approved test instruments, that equipment is dead.3 Never accept another persons word that a circuit is safe to work on; always check.4 Ensure that all supplies to equipment to be worked on are isolated at the appropriate places and locked OFF if possible, and that all supply fuses are removed and retained in a safe place. Place CAUTION MEN AT WORK notices at positions of isolation.5 If work is to be carried out on dead equipment which is adjacent to live supplies, ensure that barriers are used to define safe areas, or DANGER LIVE APPARATUS notices are placed on all adjacent live equipment.Safe isolation of suppliesThe Electricity at Work Regulations require that no live working is undertaken unless it is impracticable to work dead.All electrical circuits, apparatus etc. must, therefore, be switched off, isolated (these can sometimes be achieved by one action, e.g. switching of a circuit breaker also isolates the circuit) and, whenever possible, locked in the off position.In order to prove the system dead and safe to work on, an approved voltage indicator should be used (this is usually a test lamp). The following steps should be observed:1- Identify the circuit/equipment to be worked on.2- Ensure that it is safe/convenient to switch off.3- Isolate the supply.4- Using an approved voltage indicator: check the indicator works, on a known supply then use it to test to check the system is dead then re-check the indicator is still working, on the known supply again.5- Lock off the isolator or remove the fuse and keep in a safe place. If no locking facilities are available, post warning signs or notices.Safe use of electrical equipmentWhen one is using electrical equipment such as drills, saws, sanders, etc. On site or in a workshop, great care must be taken to ensure that the tools are in good condition and that the cables supplying them are not damaged in any way and are adequate for the job they have to do.Any connections of cables must be carried out by a competent person using approved tools and equipment.First aidNo matter how careful we are, there are times when we or our workmates have an accident. Prompt action can relieve unnecessary suffering, prevent permanent disability and, in extreme cases, save life. This action is first aid.Electric shockAn electric shock is experienced when a current passes through the body. Not everyone would have the same level of shock from the same source; it would depend on variables such as the individuals body resistance, his or her health, etc. However, it is generally accepted that 50 mA (0.05 ampere) is the lethal level. Below this level, contact with a live source throws us away from the source. Above 50 mA the muscles contract or freeze and we are unable to break contact.Electric shockAlso, interruption of the hearts rhythm takes place and its beating may stop altogether (ventricular fibrillation). Burns to the parts of the body in contact can occur, together with burning of internal organs and loss of breathing It is clearly essential that prompt action be taken in the case of severe electric shock. The following procedure must be adopted:1 Do not touch the casualty with the hands.2 Switch off the supply.3 If this is not possible, pull the casualty away from contact using insulating material, i.e. a scarf, piece of wood, newspaper, etc.4 If heart or breathing or both have stopped, apply resuscitation and cardiac massage until the casualty recovers.5 Treat for burns.6 Check for other injuries; treat as necessary.7 Treat for shock.8 Call for medical assistance.Method of resuscitationCardiopulmonaryresuscitation (CPR)

Place victim flat on back on a hard surfaceA. Open the airway If unconscious and not breathing tilt head back and support jaw

B. Breathing.Look, listen and feel for breathing. If not breathing give mouth to mouth resuscitation.Close nostrils with fingers and blow into mouth. Make sure there is no air leak and the chest expands. Give 2 normal breaths. Feel for carotid pulse in neck. If no pulse:

C.Perform chest compressions. Place both hands on the lowest third of breastbone. Depress sternum 11 inches at a rate of 80 compressions (1.5-2)inches per minute.Alternate 2 breaths with 15 compressions. Check pulse after 1 minute and every 3 minutes.