Smartglass Glass is processed to the following standards:

EN 572:  Float Glass
EN 1279 : Insulated Glass Units
EN 1863 : Heat Strengthened Soda Lime Silicate Glass
EN12150 : Thermally Toughened Soda Lime Silicate Glass
EN 14179 : Heat Soaked Thermally Toughened Soda Lime Silicate Safety Glass:                                    
EN 14449 : Laminated Glass and Laminated Safety Glass
EN 1096 :  Coating
EN: 12600 : Pendulum Impact Test Method And Classification For Flat Glass

 

DEFINITIONS OF LIGHT AND ENERGY TERMS, SPECTROPHOTOMETRIC AND THERMAL INSULATION CRITERIA.

VISIBLE LIGHT

This represents 53% of the solar spectrum and has a wavelength of 380 to 780 nanometers.  Light passing through the eye makes the brain experience the sensation of light within these wavelengths.  This measurement of daylight has been standardized by the International Lighting Committee using the 65 illuminant described in the ISO DP9050.

LIGHT TRANSMISSION LT %

This is the percentage of visible light transmitted through the glass, compared to the total visible light that reaches the glass at a 90 degree angle.

EXTERNAL LIGHT REFLECTION LR OUT %

External Light reflection is the percentage of visible light which is reflected away from the outer surface of the glass, compared to the total visible light that reaches the glass at a 90 degree angle.

 

INDOOR LIGHT REFLECTION LR IN %

This is the percentage of visible light reflected away from the inner surface of the glass, compared to the total visible light that reaches the glass at a 90 degree angle in accordance with the criteria contained in the ISO 9050-1990 standard.

 

SOLAR ENERGY

The solar energy is made up of all three wavelengths of energy within the solar spectrum:
Ultraviolet light (UV)            300 to 380 nanometers     1   %
Visible light (LT)                   380 to 780 nanometers     53 %
Infrared radiation (IR)          780 to 2150 nanometers  46  %

The standard parameters for the calculation of the energy values take into consideration all three wavelengths from 300 to 2150 nanometers, with the sun at 30 degrees above the horizon, a clear sky and sun-strike perpendicular to the glass surface.

 

ENERGY REFLECTION ER %

This is the percentage of the solar energy reflected away from the outer surface of the glass, in comparison to the total incident solar energy.

ENERGY ABSORPTION EA %

This is the percentage of the solar energy absorbed by the body of the glass, compared to the total incident solar energy.

 

ENERGY TRANSMISSION ET %

This is the percentage of the solar energy transmitted through the body of the glass, in comparison to the total incident solar energy.

 

SOLAR FACTOR SF

The solar factor of glazing is the percentage of the total solar radiant heat energy entering the room through the glass. It is the sum of the solar radiant heat energy entering by direct transmittance and the proportion of the energy absorbed and re-emitted by the glazing to the interior space.

 

DIAGRAM SHOWING ENERGY  TRANSMITTANCE

 

SHADING COEFFICIENT SC

The shading coefficient is obtained by dividing the SF by 0.87 (the Solar Factor for 3 mm float glass).  The lower the SC the better the performance of the glass.

 

U-VALUE

Heat transmittance through a surface by conduction, convection and radiation is expressed by its U-Value.  This is the rate of heat loss per square metre for a temperature difference of 1 degree Kelvin or Celsius, between the interior and exterior.