The fan extracts atmospheric gases from the tin bath and also extracts SO₂-gas mixture from the opening between dross box and lehr. The fan is located above the tin bath and is switched on and off on-site. The fans must be connected by a trained professional only.

Bypass must be opened, when the throttle valves on the pipe are closed so far that there is not enough atmosphere is sucked. This serves to protect the fan.

The SO₂ exhaust duct extracts air mixed with sulfur from above the opening between dross box and lehr. The amount of air to be extracted can be regulated by the throttle valves that are located directly above the exhaust duct.

There is one thermocouple built into every venting pipe that measures the temperature of the gas to be extracted. The thermocouples must be connected by a trained professional only.

In addition to every thermocouple, there is one probe Annubar^® that measures the flow rate of gas to be extracted. The probe Annubar^® must be connected by a trained professional only.

A flow indicator is installed on each return line of the vent, to monitor the cooling water flow. The flow indicator must be connected by a trained professional only.

The pipelines move the extracted and purified atmospheric gases outside via the tin bath. The amount of the suctioned gas can be adjusted by the throttle valves, which are installed at several points throughout the piping. Expansion joints on the piping provide easy length compensation, which is caused by the heating of the pipes during operation.