Glossary

Term

Definition

Color – Gold/Bronze

Films with positive b*; actual appearance varies along L* depending on whether the neutral colored film is light or dark.

Color – Neutral/Grey

Films with very small values for a* and b*; actual appearance varies along L* depending on whether the neutral colored film is light or dark.

Color Reflective

Films made by laminating colored films (typically brightly colored blue or green) to reflective silver films, creating a high heat-rejecting film that dramatically changes the appearance of the glass.

Dual Reflective

Tintbuyer.com defines as a difference in reflectivity between the two film sides (outside versus inside) greater than 4%.

L*a*b* Color Space

A precise 3-dimensional color system where L* is a “z” axis measure of “lightness”; a* and b* are the “x” and “y” axis measures.  L* ranges from 0 (black) to 100 (white); a* ranges from negative (green) to positive (red); b* ranges from negative (blue) to positive (yellow).

Single Reflective

Tintbuyer.com defines as a difference in reflectivity between the two film sides (outside versus inside) less than 4% and greater than 14% visible light reflectance.

Term

Definition

Emissivity (E)

The measurement of a film’s ability to reradiate absorbed energy.  A lower “E” value will be more efficient and maintaining heat generated inside a space.

Glare Reduction

Reduction in visible light transmission after installing film compared to the visible light transmission of glass with no film.

Infrared

Although not officially defined by the window film industry, Tintbuyer.com delineates “near” infrared and “far” infrared as 780-2,500 nm and >2,500 nm respectively.  Near infrared-blocking capabilities are important for reducing solar heat gain whereas far infrared-blocking capabilities are important for improving emissivity.

Luminous Efficacy

The ratio of visible light transmission to shading coefficient.  Luminous efficacy greater than 1.0 is defined to be “spectrally selective”.

Shading Coefficient

The ratio of solar heat gain through a given glazing system to the solar heat gain of clear glass.  (similar to Solar Heat Gain Coefficient).   Lower is better when heat rejection is an important consideration.

Solar Heat Gain Coefficient

The ratio of solar heat gain through a given glazing system to the solar heat gain of clear glass.  (similar to Solar Heat Gain Coefficient).   Lower is better when heat rejection is an important consideration.

Total Solar Energy Absorbed

Percentage of total solar energy absorbed by a glazing system.  Glass breakage due to application of window film is typically rare but solar absorption and uneven glass thermal expansion would contribute to potential for breakage.

Total Solar Energy Rejected

Percentage of total solar energy (heat) rejected by a glazing system.  Higher is better when heat rejection is an important consideration.

Ultraviolet Rejected

Percentage of total ultraviolet (UV) radiation that is prevented from passing through a glazing system.  Check Tintbuyer.com FREE GUIDES for more information about UV light, fading, and skin cancer.

Visible Light Reflected Exterior

Percentage of total visible light reflected by a glazing system to the outside.

Visible Light Reflected Interior

Percentage of total visible light reflected by a glazing system to the inside.

Visible Light Transmitted

Percentage of total visible light passing through a glazing system.  Higher visible light transmission is important when trying to keep the appearance of the glass the same after film installation.  Lower visible light transmission is important when glare reduction is important.

Term

Definition

ANSI

The American National Standards Institute – a private non-profit organization that oversees the development of voluntary consensus standards for products, services, processes, systems, and personnel in the United States.

Ceramic

An inorganic, nonmetallic film.

CPSC

The Consumer Products Safety Commission – an independent agency of the U.S. government  created to protect against unreasonable risks of injuries associated with consumer products.

Insulated Glass Unit (IGU) Seal Failure

Windows manufactured of two or more pieces of glass with a sealed airspace typically have desiccant to keep moisture out of the airspace.  When the seal is broken, moisture can build up between the panes.

IWFA

The International Window Film Association has an industry mission of increasing consumer awareness and demand for all types of professionally-installed window film products.

NFRC

A  nonprofit, public/private organization created by the window, door, and skylight industry that has developed a window rating system.

Radio Frequency (RF) Interference

The tendency of a film to interfere with radio frequencies (whether desired in the case of stopping electronic eavesdropping or undesired in the case of causing GPS or Tire Pressure Monitor malfunction) is an important consideration.

U-Factor

The measure of tendency for conductive heat transfer – window films in general have very little effect on U-Factor.