An emergency shut off system for a workspace enclosure, wherein a sensor array is provided for detecting hazardous conditions within the workspace enclosure. A control module is coupled to the sensor array. A pneumatic shutoff line is provided, extending between the control module and a hot work apparatus used in connection with the workspace enclosure. The hot work apparatus is responsive to pressurization of the pneumatic shutoff line to remain in an operational state. The control module is responsive to a signal from the sensor array indicating the existence of a hazardous condition inside the workspace enclosure to depressurize the pneumatic shutoff line. The hot work apparatus is responsive to depressurization of the shutoff line to be rendered non-operational.