Not sure what you mean by rubber areas? Are you talking about
respirator required? same with Vaults?
Most commercial exposure in a BWR is received in the drywell, refuel
floor, or Rx Bldg rooms...such as RWCU or RHR.
In a PWR, it is inside the bioshields (which are called vaults at some
plants) where the primary side of Steam Generators are located along with Reactor cooling pumps, etc. There is also dose to be had in the reactor cavity, near the Rx Head and in the transfer canal.
Also RHR rooms, Heat exchangers, etc.
All this being said, my personal exposure is 28 REM and change...