I have a small facility with multiple rooms, each of which is equipped with a sensor alarm that run independent of one another, all are 110V AC. If the alarm is triggered in one room only that room will alarm. I need to install an outside alarm that will sound if any of the 4 rooms are triggered while still keeping each room independent. Currently, each alarm works perfectly. If I tie into each of the rooms hot wire then tie them back together at the outside alarm, it will either trigger all the alarms or create a loop and trip the breaker (not sure). I thought I could use a relay like this Problem is I do not know if this would actually work or if there is another device I can use. Essentially what I need is a 'check valve' for 110V AC electrical so I'm a bit lost. Below is the layout. Blue boxes are the smart plugs that will switch on if triggered, the red ovals are the alarms (plugged into the smart outlets). Green lines represent tying into the wiring to the alarms so it would energize the outside alarm. Any advice would be greatly appreciated.
Thank you.

Thank you.
