These APHA/Pt-Co/Hazen liquid color standards were originally developed as references for visual APHA/Pt-Co/Hazen Color comparison to samples. Their role with instrumental APHA/Pt-Co/Hazen Color measurement is primarily as a performance qualification check of the instrument prior to measuring liquid product samples, or to validate the instrumental-to-visual correlation. HunterLab instruments have their own internal diagnostic standards to verify […]
There are no physical liquid standards specifically designed to verify the Yellowness Index of liquid samples over time. Yellowness Index is defined as a mathematical function such that a perfect clear of 100% transmission, typically represented by the transmission cell filled with DI water, will have a YI value of 0. However, a good workaround solution […]
Presses used for molding plastic plaques and sheets from pellets typically have heating/cooling platens and a programmable controller.
The original references were written by Allen Hazen, a chemist who first defined APHA/Pt-Co/Hazen color scale for the evaluation of water quality on behalf of the American Public Health Association: Hazen, A. A new color standard for natural waters, American Chemist Journal (14:300), 1892. Hazen, A. The measurement of the colors of natural waters, American […]
“APHA” stands for American Public Health Association Color Scale, the organization responsible for the original definition and implementation of this visual color scale as a standard method for rating water quality.
The APHA/Pt-Co/Hazen and Gardner visual color scales were both originally based on liquid chloroplatinate color standards but have different history and intended use.
FAQ: ” We are currently using a 10 mm path length and read in the 0 – 50 region for APHA/Pt-Co/Hazen Color, usually in the area of 10. Would you recommend a 10 mm path length with our equipment for this application?”
When used with industrial and commercial products, there is more than one definition of “opacity” as an optical property.