zoomImage Courtesy: Evac Cathelco, now part of the Evac Group, has received Type Approval for its ballast water management system (BWMS) from the US Coast Guard (USCG).The coast guard issued the 20th Type Approval certificate after a detailed review of the manufacturer’s type approval application determined the system met relevant requirements.The treatment principle of the Evac Evolution BWMS consists of filtration with UV treatment during uptake and discharge. This approval covers models with maximum treatment rated capacities between 55 m3/h and 1,500 m3/h, according to the coast guard.Evac Group already attained USCG alternate management systems (AMS) acceptance for its BWMS over four years ago.When it became apparent that the USCG’s definition of ‘non-viable’ would become the universal standard for testing systems, Cathelco said it redesigned their equipment and embarked on another round of land-based and shipboard testing which was successfully completed last autumn.This is said to be the first USCG certificate to show UV transmission (as opposed to UV intensity) as a real measurement of water quality. UV transmission data for ports around the world is readily available.The news follows the IMO Type Approval which was received in May 2019. This was to the revised G8 standard and the recently introduced Ballast Water Management Code which has much more robust definitions of the design limitations of the equipment.The Evac Evolution BWMS incorporates a feedback ‘loop’ based on the measurement of UV transmission which determines precise dosage. It automatically adjusts to different seawater qualities in harbors and estuaries ensuring the optimum UV dosage is applied at all times, but saving on power whenever possible.“We set the objective of achieving effectiveness down to 55% UVT in all salinities and we have adopted linear scaling which means that it will work on all types of vessels,” Robert Field, Cathelco’s Technical Director, explained.