Combined service notification


I´ve defined two ping services to different public sites to verify if my internet connection is workin properly.
Both notifies when the link is down, or when the ping response times out, so it sends several false-positive.

So, it is possible to define the notification to take effect when both services are in a faulty state?
I guess that would be a workaround for this situation, does anyone suggest any better?

Thanks in advance!