RMS Titanic Passenger Liner

• F Deck, the Middle Deck, was the last complete deck and mainly accommodated Second and Third Class passengers and several departments of the crew. The Third Class dining saloon was located there, as were the swimming pool and Turkish bath.
• G Deck, the Lower Deck, was the lowest complete deck that carried passengers, and had the lowest portholes, just above the waterline. The squash court was located there along with the travelling post office where mail clerks sorted letters and parcels so that they would be ready for delivery when the ship docked. Food was also stored there. The deck was interrupted at several points by orlop (partial) decks over the boiler, engine and turbine rooms.
• The Orlop Decks and the Tank Top were on the lowest level of the ship, below the waterline. The orlop decks were used as cargo spaces, while the Tank Top—the inner bottom of the ship's hull—provided the platform on which the ship's boilers, engines, turbines and electrical generators were housed. This area of the ship was occupied by the engine and boiler rooms, areas which passengers would not be permitted to watch. They were connected with higher levels of the ship by flights of stairs; twin spiral stairways near the bow provided access up to D Deck.