Page 34 - GRIHA Manual Volume III - Introduction to National Rating System
P. 34
Building and system design optimization 27
Parameters for artiicial lighting design
1. Luminaire
A luminaire is the complete assembly, which consists of the lamp together with the parts designed to
distribute light, to position and protect the lamp, and to connect the lamp to the proper power supply.
Selection of luminaire: The selected luminaire should be of a standard type that corrects
photometry, ensures uniform light distribution with suitable mounting, has louvers for glare control,
and offers necessary electrical safety and protection.
2. Photometry
The term ‘photometry’ is used to define any test data, which describes the luminaire’s light output
characteristics. The most common types of photometric data include iso-footcandle performance
charts, coefficient of utilization curves, vertical and lateral light distribution data, lumen maintenance
curves, and dirt depreciation curves. The purpose of photometry is to accurately describe the
performance of a luminaire to enable the designer to select the lighting equipment and to design
a layout plan. The photometric files are required to evaluate lighting design as prescribed by the
architect/electrical consultant.
3. Lamp (optical sources)
A lamp is a device that transforms electrical energy input to electromagnetic radiation, or light
(lumens).
The most important element of the illumination system is optical source or lighting source. It is
the principal determinant of the visual quality, efficiency, and economy aspects of the illumination
system.
Selection of lamp Selection of lamp is the most important criterion for any design. In interior
lighting design, the lamp must be of fluorescent type. Efficacy is defined as the ratio of energy
input to the lumen output (lm/watt). The lamp selection should be on the basis of efficacy and
good colour rendering index (CRI). Table 3 below indicates the different types of lamps with their
respective efficacy.
Parameters for artiicial lighting design
1. Luminaire
A luminaire is the complete assembly, which consists of the lamp together with the parts designed to
distribute light, to position and protect the lamp, and to connect the lamp to the proper power supply.
Selection of luminaire: The selected luminaire should be of a standard type that corrects
photometry, ensures uniform light distribution with suitable mounting, has louvers for glare control,
and offers necessary electrical safety and protection.
2. Photometry
The term ‘photometry’ is used to define any test data, which describes the luminaire’s light output
characteristics. The most common types of photometric data include iso-footcandle performance
charts, coefficient of utilization curves, vertical and lateral light distribution data, lumen maintenance
curves, and dirt depreciation curves. The purpose of photometry is to accurately describe the
performance of a luminaire to enable the designer to select the lighting equipment and to design
a layout plan. The photometric files are required to evaluate lighting design as prescribed by the
architect/electrical consultant.
3. Lamp (optical sources)
A lamp is a device that transforms electrical energy input to electromagnetic radiation, or light
(lumens).
The most important element of the illumination system is optical source or lighting source. It is
the principal determinant of the visual quality, efficiency, and economy aspects of the illumination
system.
Selection of lamp Selection of lamp is the most important criterion for any design. In interior
lighting design, the lamp must be of fluorescent type. Efficacy is defined as the ratio of energy
input to the lumen output (lm/watt). The lamp selection should be on the basis of efficacy and
good colour rendering index (CRI). Table 3 below indicates the different types of lamps with their
respective efficacy.
