Salinity Refractometer – P/N C280225

The C280225 Salinity Refractometer provides salinity and specific gravity readings from a small liquid sample. The handheld optical instrument supports routine checks of prepared salt solution and collected fog solution in ASTM B117 laboratory work, using the scale conversion established in the laboratory’s procedure.

Measurement Features

• Salinity range: 0–100 ppt.
• Scales: salinity and specific gravity.
• Sample size: approximately 2–3 drops.
• Automatic temperature compensation: 10–30 °C.
• Reading method: manual optical reading through an adjustable-focus eyepiece.

Using the Refractometer for ASTM B117

Place a few drops on the clean glass measuring prism, close the cover, and allow the sample and prism to reach the same temperature. Look through the eyepiece and read where the light and dark areas meet the numbered scale.

Automatic temperature compensation corrects for temperature effects within the specified operating range. The sample still needs time to stabilize before taking the reading.

ASTM B117 requires the collected solution to contain 4–6% NaCl by mass. Follow the supplied instructions to establish how the instrument’s salinity or specific gravity readings correspond to NaCl concentration by mass. A reading in ppt must not automatically be treated as percent NaCl without confirming the scale’s basis.

Both scales derive from the same optical measurement. Displaying salinity and specific gravity is convenient, but does not provide two independent measurements.

Included Accessories

• Protective storage case.
• Calibration screwdriver.
• Plastic sample pipette.
• Distilled-water solution for zero adjustment.

Care and Verification

Follow the supplied zero-adjustment and verification instructions. Clean and dry the prism between samples using the manufacturer’s recommended method. Other dissolved substances, residue, and contamination can affect the reading. Establish verification and calibration checks appropriate to your laboratory procedure, customer requirements, and accreditation requirements.

Ordering and Related Supplies

This instrument is sourced from the manufacturer, and fulfillment may take longer than standard stocked items. Confirm current lead time when ordering.

Auto Technology also supplies
pre-mixed 5% salt solution — C173300,
the
Salimeter 11-606 Hydrometer — C280220,
and the
Specific Gravity Hydrometer — C280215.

View ASTM B117 salt, solution, water, and measurement supplies.