A Brooklyn firefighter says he was seriously hurt after he slid down a fire pole that was too slick, smashing into the floor and fracturing a vertebra in his lower spine, according to a lawsuit.

Lt. Christopher Cooke, 50, of Engine Co. 254, was on the second floor of the firehouse one day last March when a report of a blaze came in.

He leaped into action and onto the pole — and found himself unable to control his descent, he claims in a Brooklyn Supreme Court lawsuit.

The Avenue U firehouse was being cleaned when someone splashed the fire pole with water, said Cooke’s lawyer, Vito Cannavo.

Cooke is seeking unspecified damages.