DMV
Stands for Drain, Waste, and Vent. Term used in plumbing to describe the system of pipes that remove wastewater while also venting the system to prevent the buildup of sewer gases and maintain proper air pressure in the pipes
what do the vent portions of DWV do
make sure that uneven air pressures don’t block the flow of water and waste, and they let harmful sewer gases escape safely out of the roof.
what does water supply piping do
it carries hot and cold domestic/potable water fixture throughout the house
what do metal nail guards do
protect DWV piping from future nail or screw damage after wallboard or other finishes are installed