ALTANA LCM III - Manual (Page 36)

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Standard Operations
cuvettes/sample cells. Hazen values below 50 are measured in 50 mm
cuvettes/sample cells. Hazen values below 10 are only be measured with
the 50 mm cuvette/sample cell used for calibration, because nearly
water-clear products can easily give faulty measuring results due to
cuvette/sample cell tolerances.
5.5.4 Determine the Gardner color value
The Gardner color value is defined in DIN-ISO 4630.The lighter
Gardner color values (1 to 8) are based on
potassium-chloroplatinate solutions, while the darker ones (9 to 18)
are based on solutions of iron(III)chloride, cobalt(II)chloride and
hydrochloric acid. The LCM III can determine Gardner values at all
cuvette/sample cell path lengths (only values 0 to 4 in 50 mm
cuvettes/sample cells).
The 10 mm and 11 mm cuvettes/sample cells provide sufficient
accuracy.
5.5.5 Mineral oil color value (ASTM D 1500 and ISO 2049)
The mineral oil color scale is used to evaluate the color of mineral
oil products such as lubricating oils, fuel oil, diesel fuel and paraffin.
The color scale starts at color value 0 for water-white, non-colored
oils and ends at 8 for very dark brown oils. Substances are visually
evaluated in multiples of 0.5 (0.5; 1.0; 1.5 etc.).The LCM III displays
the results in multiples of 0.1. For samples whose color value is
higher than 8,*** is displayed.
Note: Because of the intensive color of the ASTM D 1500 color value, it is
calculated only for 11 mm round or 10 mm square cuvettes/sample cells.
No calculation is carried out for the 50 mm path length.
5.5.6 Determine the Saybolt color number (ASTM D 156)
The Saybolt color scale is used to evaluate refined oil products
such as petrol and kerosene, as well as for petroleum waxes and
pharmaceutical white oils.
The Saybolt color properties are comparable to those of the Hazen
scale (APHA). The Saybolt color scale starts at color number +30
(lightest color, equivalent to approximately 8 to 10 Hazen) and ends
at -16 (strongest color, equivalent to approximately 350 Hazen).
Note: The measurements can be carried out with 10 mm, 11 mm or 50 mm
cuvette/sample cell path lengths. A longer path length increases the degree
of accuracy associated with the measurements (50 mm recommended).