1. Natural Sunlight
This is the best kind of light because it includes ultraviolet rays (which do not pass through glass); this destroys bacteria and so acts as a disinfectant, and acts on the skin to make Vitamin D.
2. Artificial Lighting
This is needed during the hours of darkness. Oil lamps and candles produce a lot of smoke and may cause fires if they are not placed in suitable positions. Electricity is clean and seldom causes fires unless the wiring of the house is fauly. Childr should not play with switches or fittings as they can be electrocuted. Plugs should have safety fittings.
Light is increased by well reflecting, light-coloured clean walls. Whitewashing the interior of a room improves the lighting.
In the hospital ward there are big central lights, bed-lights, and night-lights. These should be arranged for the patient's comfort; very bright lights shining on the patient can be very uncomfortable and hurtful to the eyes, and the patient may be too shy to ask to have it shaded.
Light is needed for the general lighting of a room or for some special job like reading, sewing, writing, and study. Here it should be strong enough, concentrated, and in a good position; this is also much more economical.
Water conducts electricity and it is dangerous to work switches with wet hands or while standing in water. Bathroom switches should be outside the room.
Effects Of Poor Lighting
1. Glare makes sight less sensitive.
2. Strong concentrated sources of light produce fatigue and eye strain.
3. Poor light increases strain, produces fatigue, and leads to accidents.
4. In factories strong shadows over a job can be dangerous.
5. Bad lit places encourage accidents.
6. A dark room encourages dirt. One should be able to see the dust or cob-webs.
