Our technicians are not monitoring the screen at all times and the sound playing allow with the pop-up would alert us to look at the screen.

Let me add this to the question.

We would like the audible tone on the web client, because our technicians migrate from computer to computer and change their areas of responsibility, using business views to control what is seen based on log-ins. 

Because of this, we can't use the "play a sound" notification because it only plays on the server machine. nor can we run a script on a target computers, because one day technician "bob" may be monitoring sensors 1-10 and the next he may be monitoring sensor 11-30.  We don't want to have notifications pop-up on his computer for sensors 1-10 when he is monitoring 11-30 on the screen. 

-Chuck