Electrochemical device for producing biocide solutions

A device for producing biocidal solutions comprising a flow through undivided electrochemical cell for electrochemically activating an electrolyte to produce an electrochemically activated solution which is biocidal, the electrochemical cell having an anode and a cathode, wherein the separation between the anode and the cathode is less than 3.2 mm and the electrochemical cell having a capacity to hold no more than 20 ml of electrolyte within the electrochemical cell, the device further comprising a voltage control for maintaining a voltage of between 2 and 7.5 volts across the electrochemical cell and wherein the voltage control is configured to control the current drawn by the electrochemical cell so that a constant current is maintained.