Abstract: A method of testing the integrity of a membrane of at least one filter located along a dialysis solution circuit. The method includes the steps of wetting the test membrane with an aqueous solution, expelling the aqueous solution from the filter, filling a fill chamber of the filter with a given quantity of gas after closing the gas flow lines from the fill chamber, and detecting gas flow through the membrane, which bounds the fill chamber.

Abstract: The differential mass flowmeter comprises two U-shaped tubes, arranged side by side, mutually rigidly coupled, and having their ends inserted into a support. The tubes are adapted for conveying fluid in countercurrent and are provided with an electromagnet adapted for producing oscillation of the tubes about an axis passing through the portions inserted into the support, and with at least two coils, each facing a permanent magnet for generating a signal proportional to the angle of inclination of the portion of the small tubes which is opposite to the support, to thus permit continuous measurement of mass flow rate differences between two sections of a tube.