7.7 Ballast Water Treatment Systems (1 July 2012) Where a ballast water treatment system is to be installed, it is to comply with the requirements in Sections 4 and 5 of the ABS Guide for Ballast Water Treatment and the same is to be verified by ABS.
9 Tank Vents and Overflows
9.1 General
9.1.1 Application
These requirements apply to vents and overflows of liquid and void tanks. Tanks containing flammable liquids, such as fuel oil and lubricating oil, are subject to additional requirements, which are provided in this Subsection. For hydraulic oil, see also 4-6-6/3.3.2. Vents and overflows, and inerting systems, as applicable, for liquid cargo tanks are provided in Part 5 of this Guide. Ventilators installed for ventilation of normally dry compartments, such as steering gear compartment, cargo hold, etc., are to comply with the provisions of 3-2-17/9.1.
9.1.2 Basic Requirements
9.1.2(a) Purposes of vents. All tanks served by pumps are to be provided with vents. Primarily, vents allow air or vapor from within the tank to escape when the tank is being filled, and take in air when the tank is being discharged. Vents are also needed for tanks in the storage mode to allow them to ‘breathe’. In general, vents are to be fitted at the highest point of the tanks so that venting can be achieved effectively.