Smoke is the most fatal factor in the event of switchgear room fire in power plants. As it reduces visibility and can cause fatalities by asphyxiation. This research presents a numerical study of smoke spread in switchgear rooms. This research investigates the effect of heat release rate resulted from High Energy Arcing Fault (HEAF) on studied parameters which include visibility, carbon monoxide concentration, and temperature at human level Z=1.8 m. Also, effect of exhausting smoke by multi point extraction on the same studied parameters. Fire Dynamics Simulator (FDS) is utilized to simulate 7 case studies in 16 m long, 10 m wide and 4.5 m height for switchgear room. The fire is caused by High Energy Arcing Fault (HEAF) led to damage switchgear. Results show that, as a result of increasing heat release rate the tenable conditions are worsened where the visibility is reduced, carbon monoxide concentration is increased and the temperature as well increased at the human level. Also, results show that increasing of smoke exhaust rate worsen the visibility at the human level although the CO concentration reduces with increase of smoke exhaust rate.