LIGHTING SYSTEM DESIGN

Lighting designs can be described under following sections ,
1) Interior lighting design
2) Outdoor lighting design
3) Emergency lighting design

Before design a lighting system ,required illuminance level is need to be considered .Illuminance level (Lux) is the level of light energy that are getting from a working plane .The required illuminance level of the working plane depends on the task which takes place in the particular area .
The reflectance from the ceiling ,wall and floor are important in lighting design calculations .Significance of the ceiling reflectance increase as the room area increases . White or near whiteis preferable.

Kind Of Lighting Sources -:

1) Tungstan filaments
2) Tungstan halogen filament
3) High pressure mercurt tungsten discharge (blended)
4)High pressure mercury discharge (fluorescent)
5)High perssure mercury discharge(metal halide)
6) Low pressure mercury discharge
7) High pressure sodium discharge
8)Low pressure sodium discharge

Colour of the light sources are categorise as warm , intermediate & cool.
Light fittings may be divided in to three categories
a) General utility fittings which are designed to give effective & economical illumination.
b) Special fittings usually with optical arrangements such as lenses or reflectance to give directional lights
c) Decorative fittings in which the light is there to be seen rather than to provide light to perform task

Lighting Calculation Equation -:

No of luminaries = (lux level required * area of room)/ (N* lumenous per lamp*UF*LF)

N= no of lamps for light fitting
UF= Utilization factor
Ha= height from worrking plane to light
MF= Maintanance factor
RI= room index = area/Ha(L+W)
L= length of room
H= height of room





Emergency Lighting-:

There are two kind of emergency lighting .Escape light & standby lighting . Escape lighting is safe exit for building occupants by providing appropriate visual conditions.Stand by lighting need to continue normal activity .