Guy's, We are presently preparing to carry out a welding task within a pressurised habitat within a process area of an oil and gas installation. During a discussion with one of my colleagues he is of the opinion that the habitat should be classified as a confined space due to the introduction of vapors from the welding equipment and gasses being used for any cutting etc. I personally have never seen or experienced this type of control being put in place in the past and I am curious to know whether this is overkill or whether I have been incorrectly risk assessing the use of pressurized habitats over the last 25 ears? Any advice and/or constructive opinions would be greatly appreciated. Regards

As a pressurised habitat is designed to force breathable air through the enclosure, dilute fumes from welding processes and keep potentially flammable / explosive fumes and gasses away from the point source of ignition it would not be termed a Confined Space. If the air transport system was not functioning then yes you would be working in an area where oxygen could be depleted and dangerous fumes could accumulate but then I don't perceive it would be permitted by the risk controls to allow cutting / welding in such circumstances

In my experience pressurised welding habitats are NOT classed as confined spaces. As others have said, it probably academic anyway, as the required control measures are already in place. Classification of confined spaces is usually restricted to there being a defined confined space situation as given in the Confined Spaces Regs. Typically vessel entry, sewers/drains, trenches, enclosed structures etc