Reddit reviews Trapped at Pearl Harbor: Escape from Battleship Oklahoma (Bluejacket Books)

Similarly, there were over 400 men lost on the USS Oklahoma, second only to the 1,100+ on the Arizona. Unlike WV, the Oklahoma was not counter-flooded in time and did capsize -- within about 12 minutes -- leaving only her bottom and part of the starboard side above water once her superstructure hit the bottom. This is visible in the photo referenced earlier. She was due to have an inspection, so the internal hatches to her protective torpedo blisters along her hull were opened, which caused very fast catastrophic flooding after being hit by five torpedoes. Some trapped crew escaped by swimming down and out of the ship. Others were trapped deep in the ship’s hull which, unlike those men trapped in the water pump room on West Virginia, placed them near the surface once she turned over. Rescuers immediately began trying to save the men inside Oklahoma by cutting into the shell plating and bottom. The rescuers tried oxyacetylene torches but ended up causing the deaths of trapped sailors when the cutting torches allowed the escape of the pressurized air pockets in which the men were awaiting rescue. The thick steel plate and armor could not be cut fast enough to prevent drowning. These torches cutting into the ship also consumed the oxygen in the internal compartments and caused the interior red lead-based paints and bulkhead insulation to catch on fire, causing poisonous gases to form. (The workers at Pearl did not have oxygen electrode cutting torches until well into the salvage operations.) Thirty-two men ultimately were rescued from the Oklahoma on Dec 8 and 9, largely cut out of the ship by workers using pneumatic air tools to cut the heavy steel. As the last men were removed from the ship, the water was lapping up to the top of the rescue holes, forcing the men to hold their breath as they waited to be rescued. A great book for this is Trapped at Pearl Harbor: Escape from Battleship Oklahoma by Stephen Bower Young. Mr Young was one of the 32 men rescued and his experience was nothing short of harrowing. The rest of the men on Oklahoma could not be reached and the banging from inside the ship stopped after Dec 10. The salvage of Oklahoma and recovery of the bodies of the lost crew is discussed in the Raymer book. (Many of the parbuckling and refloating techniques used for the Okie were used recently to salvage the cruise ship Costa Concordia at Giglio.) Many of these men were buried in common graves in Hawaii because their remains were in such poor condition. However, they were exhumed this year and new DNA ID techniques are proving successful in giving these men their names back so they can finally go home to their families. Several media stories have been published recently about this identification effort.

TL;DR - Thirty-two sailors were rescued from USS Oklahoma. Some trapped crewmen died when air escaped during the rescue. Others asphyxiated when torches consumed oxygen or started toxic smoke and fires. (Added as edit)