|Profession:||Engineer, San Gabriel Island nuclear power plant|
|Died:||Lethal radiation exposure|
|Played by:||Todd Kimsey|
|Episode:||"Day 4: 3:00pm-4:00pm"|
Rosner contacted CTU Los Angeles via videophone and told them that the radiation levels in the plant were at 500 rem, which is 10,000 times the dose of an x-ray. He warned that the radiation would soon spill into the atmosphere and continue to spread until the plant's core exhausted itself.
Secretary Heller and Erin Driscoll saw that he and his co-workers were covered in radiation burns, prompting Secretary Heller to tell him to get out of the building. Rosner explained that evacuating wouldn't make any difference at that point, and the visual and audio feed went dead.
He and his co-workers died as a result of their exposure.
- James Heller: Son, you've done everything you can. Now get the hell out of there!
- Derek Rosner: Evacuating won't make any difference, sir. We've already been exposed. ("Day 4: 3:00pm-4:00pm")
Background information and notes
- In a deleted scene from Day 4: 4:00pm-5:00pm, the total casualties at the power plant were confirmed to be 12, with survivors likely to develop cancers in 5 years.
- Rosner bears resemblance to John Brunner in Day 7. Both men were in charge of the facilities targeted by terrorists and ultimately gave their lives to prevent total catastrophe.