Blogs
Source for the APHA/Pt-Co/Hazen Color Standards
Posted on by Ganesh Ramanathan
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 […]
What standard do I use to verify Yellowness Index Performance?
Posted on by Ganesh Ramanathan
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 […]
What resources are available for making plaques and sheets from plastic pellets?
Posted on by Ganesh Ramanathan
Presses used for molding plastic plaques and sheets from pellets typically have heating/cooling platens and a programmable controller.
References for Hazen Color Scale
Posted on by Ganesh Ramanathan
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 […]
Where can Liquid Gardner Color Standards be ordered?
Posted on by Ganesh Ramanathan
APHA = Pt-Co = Hazen = PCU = Platinum Cobalt Color
Posted on by Ganesh Ramanathan
“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.
APHA/Pt-Co/Hazen vs Gardner color scales: What’s the difference?
Posted on by Ganesh Ramanathan
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.
What Path Length Cell should I use for APHA/Pt-Co/Hazen Color Measurement?
Posted on by Ganesh Ramanathan
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?”
Contrast Ratio Opacity
Posted on by Ganesh Ramanathan
When used with industrial and commercial products, there is more than one definition of “opacity” as an optical property.