Atmosphere conditioning pump
The atmosphere conditioning pump was a component of a starship's life support system. To prevent life support failure, atmosphere conditioning pumps were regulated by seven independent safety interlocks. If these interlocks failed, the pumps entered into negative mode and life support terminated.

When the  was hijacked by Data in 2367, he was able to set the atmosphere conditioning pumps on deck 1 to negative mode to terminate life support on the deck. ()
Life support technology