How do I make a PIR sensor switch on mains power safely please?

Hi.

How do I make a PIR sensor switch and mains power safely please? I was thinking along the lines of LED strips and laser displays.

Currently I have a PIR wired up with a mosfet to turn on an Arduino, which turns on low voltage components. This is all connected to one battery pack. I would prefer that the same PIR sensor was used to turn on the mains, but no complaints if it's much easier to use a separate one.

Ta

A relay module ?