Urine Hydrometer

The Jolles-type urine hydrometer is a laboratory instrument designed for the precise determination of relative density in urine samples, making it a fundamental tool in routine clinical analysis.

Made entirely of glass, it has a robust structure and a length of 145 mm, which facilitates its handling and reading. Its measuring range covers from 1.000 to 1.060 kg/m³, with subdivisions of 1 unit, allowing for a detailed evaluation of the urine concentration status.

The instrument is calibrated at 20 °C, so, in case of working at different temperatures, it is necessary to apply corrections using compensation tables to ensure the accuracy of the results.

Its operation is based on the principle of flotation: the hydrometer is introduced into the sample contained in a suitable cylinder and its immersion level varies depending on the density of the liquid. The reading is taken at the point of intersection of the meniscus with the graduated scale.

This method allows for the evaluation of the kidney's concentration and dilution capacity, as well as the detection of alterations in the patient's hydration status, without the need for additional reagents.

To obtain reliable measurements, it is recommended to use bubble-free samples, at a homogeneous temperature, and in containers that allow for the vertical flotation of the instrument.

As an alternative or complement, clinical refractometers with automatic temperature compensation (ATC) can be used, which allow for rapid determinations from small sample quantities.