Pipe purging equipment seals the two ends of pipe on each side of the weld to ensure a clean, quality weld. Purging is done when TIG welding stainless steel and aluminum to ensure that welds don't adversely affect corrosion resistance. Oxygen purge monitors measure the amount of oxygen in a purge area to ensure levels are within limits to ensure quality welds. Purge bladders fill with air and can be reused. Purge dams made of dissolvable paper are preformed to fit pipe, speeding application. Purge gas retaining tape holds purge paper in place. Purge paper is cut to size to suit the application. Purge paper and tape dissolve with water or steam when work is complete. Purge plugs seal short runs of small diameter pipe.