um, the LA Times needs a machining editor. plasma cutters do not operate with any containerized gases. They use a stream of compressed air passing through a electric arc. and this line:

"a water jet does the job using sand"

...makes my head asplode. A WATER JET uses a highly pressurized stream of WATER to cut materials. Damned al Queda loving liberal media, telling lies about america's strategic metal cutting systems.