“If you can not measure it, you can not improve it.”

– Lord Kelvin, pioneer in absolute temperatures


Polishing concrete can be thought of as an art as much as a science. To be blunt, there are techniques that might be used to make a floor “appear” to be within agreed upon specs, even when it’s not. Most importantly, one cannot possibly verify that a job has been done correctly without consistent means to precisely measure results. That’s where the Runyon Data Service comes in, the best way to accurately score a floor.


Gloss is an aspect of the visual perception of objects that is as important as color when considering the psychological impact of products on a consumer. It has been defined as: the attribute of surfaces that causes them to have shiny or lustrous, metallic appearance.

The gloss of a surface can be greatly influenced by a number of factors, for example the smoothness achieved during polishing, the amount and type of coating applied or the quality of the substrate. Because of this, it is imperative that we have a way to define “quality,” or a job well done. This requires a measurement. And it is for these reasons that many businesses monitor the gloss of their floors to achieve excellence and consistency.


Gloss is measured by shining a known amount of light at a surface and quantifying the reflectance.

The angle of the light and the method by which the reflectance is measured are determined by surface, and also aspect of the surface appearance to be measured. ISO 2813 and ASTM D523 (the most commonly used standards) describe three measurement angles to measure gloss across all surfaces. Gloss is measured in gloss units (GU) and is traceable to reference standards held at NIST.

Universal Measurement Angle: 60°

All gloss levels can be measured using the standard glossmeter measurement angle of 60°. This is used as the reference angle with the complimentary angles of 85° and 20° often used for low and high gloss levels respectively.

Low Gloss: 85°

For improved resolution of low gloss, a grazing angle of 85° is used to measure the surface. This angle is recommended for surfaces which measure less than 10GU when measured at 60º. This angle also has a larger measurement spot which will average out differences in the gloss of textured or slightly uneven surfaces.

High Gloss: 20°

The acute measurement angle of 20° gives improved resolution for high gloss surfaces. Surfaces that measure 70GU and above at the standard angle of 60° are often measured with this glossmeter geometry. The 20° angle is more sensitive to haze effects that affect the appearance of a surface.

Runyon Data Services will define the shine!