Isorem
An isorem was a measurement of radiation.

In 2376, the Vaadwaur homeworld was heavily contaminated with radiogenic particles with levels starting at 3,000 isorems.  entered the planet's thermosphere, hoping that a pursuing Turei vessel's shields would not be able to withstand that level of radiation. At 6,000 isorems the pursuing vessel's shields began to weaken forcing them to withdraw their pursuit. ()

In 2378, antimatter radiation levels on Otrin's homeworld were also found to be at 6,000 isorems. ()

de: Isorem
Radiation
Measurements