Conducting ‘hot work’ on the longwall face with the risk of the presence of goaf gas is a problem for conducting ongoing maintenance and repairs on equipment underground.

Mine site personnel at the Southern operation developed the concept of a portable enclosure with the aim of providing a safe environment to conduct ‘hot work’ without the risk of gas being present. Originated by previous general manager, Mitch Jakeman, the design was implemented by Mark Parcell and Sean Cross.

A positively ventilated, portable, flexible enclosure was designed to reduce the risk of a sudden release of gas into the mine ventilation network at the hot work site.

The structure was designed using fire resistant double strength canvass sections, joined with Velcro and an adjustable frame, allowing it to be modified to fit the profile of any equipment under repair.

A filtered compressed air supply supplies workers inside the enclosure while a positive pressure prevents air from the ventilation circuit entering the enclosure. A venturi air mover and flexible ducting is the fume extraction system.

To date, the welding enclosure has not yet been used in practice but it is on site and available, Parcell said.