Continued:

Wiring can also fail due to faulty installation, physical damage, aging and deterioration by chemical action, heat, moisture and weather. Such wiring should be replaced and new circuits installed as soon as the defects are detected. 

If outlets or switches feel warm, shut off the circuit at the breaker or fuse, and have them checked by a qualified electrician.  Check cords for fraying, cuts, cracks, and immediately replace any cords that are damaged.   

Do not overload extension cords, or run cords over doorways or under carpets.  Use extension cords wisely.  Make sure they are heavy enough for the job. Avoid creating an octopus by inserting several plugs into a multi-plug outlet connected to a single wall outlet.  If you find the need to do this, add additional circuits or outlets so you do not have to use extension cords.  Use three-prong grounded cords for all equipment 

Keep all electric appliances away from water.  Be especially careful in the kitchen and the bathroom.  GFCI’s (ground-fault circuit-interrupters) should be installed to prevent someone from receiving a shock should water come in contact with electricity. 

If an appliance gives off smoke or a burning odor, unplug it immediately and have it checked by a qualified technician.  Check appliances and equipment for loose connections. 

Never use water to put out an electrical fire.  Call the fire department, immediately, give them your address and tell them it's an electrical fire. Use a carbon dioxide extinguisher if the fire is small.  If in doubt, get everyone out. If the fire is large, do not try to handle the fire yourself. 

In homes with small children, unused wall receptacles should have plastic safety covers. Good housekeeping greatly reduces the risks for a fire.  Unprotected light bulbs in work areas are another potential hazard. They can be hit and broken causing a fire. Electrical wiring can be hit when drilling holes or driving nails in walls causing a fire.