The colour is an important indicator for product quality and process control

• An important property of a cargo to assess the required cleaning intensity
• A key indicator for Wall Wash Test
• A quick check on contamination of cargoes

APHA or Hazen or PtCo Colour

“APHA” stands for American Public Health Association Color Scale. The scale ranges from distilled water at 0 (distilled water) to 500 (pale yellow). Intermediate Pt-Co colour standards are made by dilution of the Pt-Co stock solution as described in ASTM D1209.   APHA/Pt-Co/Hazen is used in the chemical and plastics industries to differentiate trace amounts of yellowness in near colourless liquid samples.

ASTM Colour

ASTM Colour scale is specified in ASTM D 1500 and ASTM D 6045 and is widely used for petroleum products including lubricating oils, heating oils and diesel fuel oils with colour characteristics ranging from standard white to dark red/brownish.
Units: 0 – 0,5 – 1,0 – 1,5 – 2,0 – 2,5 – 3,0 – 3,5 – 4,0 – 4,5 – 5,0 – 5,5 – 6,0 – 6,5 – 7,0 – 7,5 – 8