This document gives guidelines for fulfilling the requirements contained in ISO 6183:2022, 5.2.1 g) and 6.4.1, and ISO 14520-1:2023, 5.3 h) and 7.4, in respect to over- and under-pressurization venting and post-discharge extract. It considers the design, selection and installation of vents to safeguard the structural integrity of enclosures protected by fixed gaseous extinguishing systems and the post-discharge venting provisions where used.