Total Oil and Grease (OGH) is a gravimetric analysis of oil and grease in water samples through extraction with hexane. It is applicable to the determination of relatively non-volatile hydrocarbons, animal fats, vegetable oils, waxes, soaps and greases from surface waters or industrial, domestic and aqueous wastes.
OG by IR (TPHIR/MOG)
In Oil and Grease analysis using Infrared Spectrometry (Oil and Grease by IR, OGIR), samples are extracted using the organic solvent tetrachloroethylene. The oil and grease will be any material extracted. The infrared method is designed for samples that might contain volatile hydrocarbons that otherwise would be lost in the solvent-removal operations of the gravimetric procedure. Also the IR method provides sensitivity for low levels of oil and grease.
OGH – Sheen (visual)
Oil and Grease (Sheen) is a visual inspection made by senior staff in sample reception, typically when handling gas plant water samples. The senior staff member inspects a sample container with a wide mouth lid for any oil, grease or otherwise petroleum-related sheen on top of the water, and the result of the visual sheen test is noted in the final report.