What the cleaner does in the moment
Contact the monitoring provider with the site password so a patrol is not dispatched unnecessarily, notify the client's after-hours contact, and stay on site. That last item matters: leaving the building after setting off an alarm creates a far worse situation than remaining and explaining. The cleaner does not reset the panel, does not investigate which zone triggered, and does not attempt to silence it by any means other than the agreed procedure.
Those instructions are written into the site instruction with the actual numbers and the actual password arrangement, because trying to remember a procedure while an alarm is sounding is not realistic. Testing that arrangement during mobilisation, including confirming the password works, is a small exercise that prevents a genuine problem on the first occasion it is needed. Testing it during mobilisation is a five-minute exercise with a disproportionate payoff.
