English to Spanish Science Medical: Pharmaceuticals

I'm looking for the right translation for the term dead legs, I´m not quite sure what it could mean in this case because there isn't much context. The doc. is a CAPA report on a compliance platform. Also the abbreviation DM is giving a headache :S

The sentence is this:
Supply line from DM generation to storage tank for micro lab to be disconnected to avoid dead legs

Proporcionar línea de generación de DM al tanque de almacenamiento para desconectar el laboratorio de microbiología a fin de evitar el entumecimiento de las piernas.