Jumper
Jumper turns up in 2 fields: nuclear, fiber optics. Here is what it means to the people in each one.
Jumper in nuclear
A worker who makes brief entries into very high radiation spaces, absorbing a large dose allowance in minutes.
A worker assigned to quick, choreographed entries into extremely high dose-rate locations, classically the steam generator channel head, to install nozzle dams, plug tubes or place equipment. With fields in the tens of rem per hour, a jumper's allowance is used up in minutes, so crews send several jumpers in short turns. Robots and remote tooling take over much of this work, and mock-up rehearsal cuts every second inside.
"Nozzle dam install needs four jumpers, two minutes each in the bowl, so rehearse it on the mock-up first."
Jumper in fiber optics
A short fiber cable with connectors on both ends, used to patch equipment to panels or panels to each other.
A factory-made fiber cord with connectors at each end, usually simplex or duplex zipcord in 1 to 30 m lengths. Jumpers connect transceivers to patch panels and link panels in cross-connects. Their connector type, polish, fiber type and polarity must match both ends, and they are the cheapest and most often replaced part of a link.
"Port's down, swap the jumper for a new one from the bag before we start chasing the backbone."