All living organism need light energy to survive.

1. Dr. Rahul B. Pandit
Faculty of Nursing
Sassoon General Hospital, Pune
ENVIRONMENT
: LIGHT

2. • All living organism need light energy to
survive.
INTRODUCTION

3.  Amplitude
 Wave speed
 Wave length
 Frequency
PROPERTIES

4.  Sufficient
 Distribution
 Absence of glare
 Absence of sharp shadow
 Steadiness
 Color of light
 Surrounding
REQUIREMENTS

5.  Luminous intensity
 Luminous flux
 Illumination
 Brightness or liminance
MEASUREMENT OF LIGHT

6.  Visible sky
 Reflection
 Natural light
Planning of house
Removal of obstruction
windows and door
Interior of room
SOURCES OF LIGHT

7.  Man made light
 For human to function properly
 It is required when day light is not
effective
 All artificial light can be turn on off with
switch.
ARTIFICIAL LIGHTING

8. 1. It cause degradation of bilirubin.
2. Stimulate production of melanin in skin and
vitamin D
3. Increases food comsumption.
BIOLOGICAL EFFECT OF
LIGHTING

9.  Tungsten lighting
 Halogen lighting
 Fluorescent lighting
 High density discharge lamp
METHODS OF LIGHTING

10.  Invented by Thomas Edison
 Used tungsten filament
 Electricity passes to filament it gets heated up and produce
light.
Advantages
• Cheap and easily available
• Suitable for small area
• Safe handling
Disadvantages
• Not suitable for large area
TUNGSTEN LIGHTING

11. • This is incandescent bulb uses halogen gas.
• Halogen gas increases the light output
Advantages
• Easy to handle
• Longer life
• Brighter that tungsten bulb
Disadvantages
• Expensive
• UV ray damage collagen fibers of the skin.
• Continuous exposure lead to formation of cataract.
HALOGEN BULB

12. • It is narrow long glass tube.
• This tube filled with gas argon, eon or krypton
• White light
Advantages
• Cheaper
• Long life
• Now a days colorful
Disadvantages
• Complex connection
FLUORESCENT LIGHTING

13. • High Density Discharge Lamp widely used in
stores, street.
Advantages
• Brighter
Disadvantages
• Glare
• Expensive
HIGH DENSITY
DISCHARGE LAMP

14. • It is most efficient form of lighting
• Very economical
• Long lasting
• Produce more light
• Expensive
• LED contain arsenic and other harmful
substances.
LIGHT EMITTING DIODES