The best location for the vent is the riser.
ECS uses the patented “fill and purge” breathing process to remove oxygen from the fire sprinkler system. Fill and purge (pressure cycling) thoroughly mixes and homogenizes incoming nitrogen with the air in the piping to dilute the oxygen concentration as it is vented to 98% nitrogen purity. This allows for placement of the venting device anywhere on the system piping.
The best location for the vent is the riser as this provides easier installation, commissioning, and serviceability throughout the life of the corrosion management system.