Drain nozzle (forward jet)

A forward-jet drain nozzle has one or more orifices directed in the direction of travel, typically with a small backward jet for propulsion. The forward jets cut into hard blockages such as compacted wipes, fat plugs or scale, allowing the nozzle to penetrate where a purely propulsion nozzle would stall. Forward-jet nozzles are used as a second-stage tool once a partial flow has been re-established, and are particularly useful in cast iron and clay drains. Working pressure depends on the host pipe condition, with engineers selecting the lowest pressure that achieves the cleaning result, in line with the Water Jetting Association Code of Practice. Forward jets should always be used with the operator in a safe position, since nozzle reaction can be significant.