Control room habitability during severe accidents is assessed. The potential levels of radiation hazards to control room personnel are evaluated in terms of magnitude and occurrence probability. The cumulative probability distributions of control room doses, and the expected values for the probabilities of exceeding appropriate dose limits, are determined. The control room types analyzed include designs with filtered local intakes only, filtered recirculation only, filtered local intakes with recirculation, and filtered dual remote intakes with recirculation.