Many sinks, toilets, geysers and washing machines have small shut-off valves (also called angle valves) on the pipes that feed them. If a hose bursts, a tap fails or a toilet runs uncontrollably, knowing how to turn off just that one valve lets you stop the immediate problem without cutting water to the whole house.
In a stressful moment – water spraying or overflowing – being able to quickly reach under the basin or behind the toilet and turn a small knob can limit damage to a few towels’ worth instead of a full flood.
It’s worth taking a few minutes when things are calm to locate these valves, test that they actually turn, and explain them to other adults in the home. Then, if something goes wrong, you’re not panicking and hunting for the main shut-off in the middle of the chaos.
It’s a tiny piece of knowledge that can make a huge difference on a bad day.