The Janus loop was a MACO training program in the 22nd century, which included extensive experience in an EV suit, as well as EV combat training.
Corporal Hawkins did six months in the Janus loop, a fact which led Lieutenant Malcolm Reed to select him for a mission to infiltrate a Delphic Expanse sphere in 2154. (ENT: "The Council")
It is unknown whether the Janus loop is related to the Saturnian moon
Janus. Titan, a neighboring moon, was used for training execrises on numerous occasions.