What is the Gardner Scale for Color Testing?

When it comes to flooring products do you ever wonder, how clear is clear?

Industrial flooring specialists rely on tests like the Gardner Color Scale to determine the level of clarity in a topcoat and other products used to finish a high-performance floor. With a standardized color measurement to grade the amount of transparency in a liquid, we can achieve the look our customers want, when the finished floor is revealed.

The Gardner Scale Defined

Since the 1920’s, manufacturers use a visual scale called the Gardner Scale to describe the color of resin solutions and varnishes as well as other chemical liquids such as drying oils, fatty acids and polymerized fatty acids. For about 40 years, the scale consists of 18 liquid standards arranged in sealed glass tubes for visual comparison, from light yellow (1) to dark brown (18). At this time, the Gardner Scale also relies on human analysis to grade the degree of transparency, clarity and consistency of color, making the measurements subject to inaccuracies and difficulties in maintaining uniformity. The liquids are vulnerable to instable color variation and are eventually are replaced by glass filters.

The Gardner Scale Evolves

In 1997, scientists introduce a new spectrophotometer-based Gardner Scale methodology that accurately determines the translucent quality of a liquid, providing the reliability and level of consistency the flooring industry needs. The new Gardner Scale correlates with colorimetric scales such as the CIE Chromaticity Coordinates, which leads to the development of ASTM D1544, Standard Test Method for Color of Transparent Liquids – otherwise known as the Gardner Color Scale. The use of spectral analysis and the detailed chromatic data it provides allows manufacturers to identify divergences from color standards that warn of potential issues with the raw material or the manufacturing process of a product.

How a Topcoat’s Color Affects a Floor

If you think the sole purpose of a topcoat sealer is to protect a floor, think again. Degrees of yellow to brown coloring in a topcoat can change the finished look and color of an industrial floor, especially one with a decorative technique. Reviewing a product’s Gardner Color Scale rating before application will help anticipate its aesthetic affect.

The Beauty of a Polyaspartic Topcoat

Rather than penetrate into concrete, polyaspartic topcoats seal the floor at the surface, filling small cracks, smoothing already-damaged areas and providing long-lasting protection against damage due to high traffic, abrasions and spills. The one- or two-component urethane product bond well with the concrete substrate and offer excellent hardness. Some call it a miracle product.

Another of the many miracles of polyaspartic topcoats is an excellent rating on the Gardner Color Scale. Our self-branded topcoat, SS449, is a two-component 95% solids polyaspartic aliphatic sealer that is virtually transparent and provides superior aesthetic results. It is more durable than epoxy sealers and can be used on everything from standard industrial color flooring, resinous concrete floors, heavy traffic commercial surfaces, seamless flake and monolithic quartz systems. Its rapid curing rate dries in a matter of hours, guaranteeing a short downtime. SS449 is recommended for the installation of medium build broadcasted floors or where a thin to medium build sealer is needed over a troweled system. Our customers love SS449 for its durability, great appearance and lightning fast drying time – an important attribute when quick turnaround time is a priority, such as jobs in the food and beverage industry, manufacturing or retail. SS449 can be applied overnight, so the business is up and running the next morning.

Get a look at successful industrial flooring system installations completed by Surface Solutions by visiting our Work Showcase.


Recognized as a top UCRETE® Master Contractor since 2012, Surface Solutions, Inc. is an independent industrial floor contractor specializing in seamless, polymer flooring systems utilizing the most trusted brands in the industry. As a Flowcrete STAR Contractor, Surface Solutions, Inc. is a leading provider of industrial flooring solutions for the Food & Beverage industry. From testing to consultation and complete installation services, Surface Solutions is your premier source of non-toxic, safe and environmentally friendly flooring systems, offering turnkey installations using only in-house personnel. All installations come with a complete single source warranty. To learn more about how Surface Solutions can help provide the highest quality industrial flooring solutions for your business, contact us today!