If the other control room is contaminated now, wasn't it unsafe to work in after the explosion? They still had a few reactors in operation for a time.
Good to see the control room still runs Windows XP with default Teletubby background. I wonder whether this is a vulnerability and an upgrade is planned.
There are three control rooms mentioned, it seems - the current 'Arch' control room and the original control rooms for units 3 and 4. Article says that even the unit 4 control room was once decontaminated and stripped of equipment. The unit 3 one is the one that was used for years after.