Glassary - U

Ultraviolet transmittance:
the proportion of incident UV radiation transmitted by the glass, expressed as a fraction.

Unit:
an abbreviation of insulating glass unit.

U value:
a measure of the rate of heat loss through the wall of a building material. Also described as thermal transmittance. U values depend on several different variable factors, such as wind speed and temperature, so they are usually quoted in relation to a specific set of steady state environmental conditions.

UV curing resin:
a resin that has to be exposed to UV light in order to cure. This sort of resin is used in the manufacture of cast-in-place laminated and for sticking decorative features such as applied bevels to glass.

UV filter interlayer:
an interlayer in a laminated glass, which blocks the majority of the UV radiation.
See Product Data Sheets on Pilkington Laminated Safety Glass and Pilkington Anti-Fade™

UV Filter Layer:
an alternative term for UV filter interlayer. See Product Data Sheet on Pilkington Laminated Safety Glass and Pilkington Anti-Fade™

UV light:
an alternative term for UV radiation.

UV protection:
an alternative term for UV reduction.

UV radiation:
the part of the electromagnetic spectrum with a slightly shorter wavelength than visible light, within the UV range, known as ultraviolet light or UV light.

UV range:
the wavelengths of the electromagnetic spectrum usually described as being UV radiation. There are two common descriptions, the ISO range (280-380 nanometers nm) and the Parry Moon range (from 300-400 nanometers nm).

UV reduction:
the proportion of UV radiation, which is blocked by the glass.

UV Screen ™:
This is the old brand name for Pilkington Anti-Fade™ (see Product Data Sheet) our range of Cast-in-place, laminated glass.

These products incorporate a special UV filter interlayer that depending on the product selected can greatly reduce or eliminate altogether UV transmittance.

UV transmission:
an alternative expression for UV transmittance, expressed as a percentage.

UV transmittance:
the proportion of incident UV radiation transmitted by the glass, expressed as a fraction.