APHA/Pt-Co/Hazen vs Gardner color scales, which parameter should I choose?

APHA/Pt-Co/Hazen vs Gardner color scales, which parameter should I choose?

Gardner Color Scale

The Gardner color scale is used to differentiate between yellow samples of higher chromaticity that also vary in brightness and hue. Originally based on liquid chloroplatinic acid standards, the Gardner color scale definition was reset in 1958 with a set of 18-color filters designed to match the colors of the original liquid standards.

The Gardner color scale ranges from 0 (distilled water) to 1 (light yellow) and then all the way up to a deep, dark 18. In the 0 to 18 range, the yellowness increases, the brightness decreases, and the hue changes from reddish yellow to greenish yellow. Most applications have a Gardner color between 0 and 8.

APHA/Pt-Co/Hazen Color Scale

In the chemical, pharmaceutical and plastics industries, APHA/Pt-Co/Hazen is used to distinguish trace amounts of yellowness in samples of near colorless or low chroma liquids.APHA/Pt-Co/Hazen ranges from 0 (distilled water) to 500 (pale yellow) and is used to distinguish trace amounts of yellowness in near “water white” liquids. .

What's The Difference Between APHA/Pt-Co/Hazen & Gardner?

The intersection of the APHA/Pt-Co/Hazen and Gardner Colorimetric Chromaticity is at the high end of the APHA/Pt-Co/Hazen Colorimetric Chromaticity scale and the corresponding low end of the Gardner Colorimetric Chromaticity scale.The APHA/Pt-Co/Hazen 500 Colorimetric Chromaticity scale is considered to be slightly lower than the Gardner 2 Colorimetric Chromaticity scale.

In some applications, it is possible to combine APHA and Gardner colorimetry to assess color quality during processing. A material may start out as a high yellow liquid with a medium Gardner Colorimetry. After refining, the color quality improves to a Gardner's Chromaticity of 2 or 1 with a reduced degree of yellow. As the refining process continues, the product takes on a more watery white color. As the product is further refined to near the desired color endpoint of water, it can be measured using the APHA. The final measurement can also be used to document the “APHA color less than 30” sales quality specification.

Which instrument should I choose?

CHNSpec DS-816N can measure Hazen and Gardner at the same time, which will be your best choice.