During Khazid Kro you will reach a point where you must hold out in the brewery while the engineer gives you instructions of which valves to turn. He will direct you from valve to valve until things are corrected and he opens the door. The brewery is not large, the only things truly that will slow you down are the waves of enemies that pour into it.
He will give the valve locations all within the 240 seconds if you go directly from valve to valve as he calls them out. On easy I had to turn four until he had fixed the brewery.