What is isolating hazard?

If you isolate a hazard you place it where it is not possible to a person to be exposed to it. You do this by putting it out of reach or by enclosing it or placing other barriers between it and the people it might hurt.

You might place moving belts with pinch points near the ceiling where they are our of reach. You might enclose a noise source in such a way that the sound cannot get to people. These are examples of isolation.