Plumbing ventilation means to ______.
A. carry sewer gas out and relieve pressure of the drainage system
B. discourage corrosion in the drainage piping
C. maintain the trap seals
D. give pressure differentials in the public sewer
Answer:A
Plumbing ventilation means to ______.
A. carry sewer gas out and relieve pressure of the drainage system B. discourage corrosion in the drainage piping C. maintain the trap seals D. give pressure differentials in the public sewer