Some Information about Plumbing and Plumbing tools
A check valve is a mechanical device, a valve, that normally allows fluid to flow through it in only one direction. A double check valve is often used as a backflow prevention device to keep potentially contaminated water from siphoning back into municipal water supply lines. A clapper valve is a type of check valve used in or with firefighting, and has a hinged gate (often with a spring urging it shut) that will only remain open in the outflowing direction.
Some Plumbing DOs and DON'Ts
DO - Keep these items away from the toilet.
DON'T - Let the children play in the bathroom with toys small
enough to go down your toilet trap.
DO - Get in the habit of putting the back of the toilet seat
down before flushing.
DO - If you have a water leak from below your bathroom directly
below Your bath tub shower, and it only leaks when YOU take a
shower, here's what to look for: