The error code indicates heap corruption. That means that, barring a hardware issue, Explorer is loading something that is causing it to crash. You said this is happening on multiple machines so a hardware issue seems unlikely.
Personally I would take a look at the reliability monitor in Windows. Identify when the crashes started happening and then look to see what changed on the system at that time. Most likely either an application was installed or an update occurred and that is causing the error. If you can identify what it is then remove it and confirm Explorer is stable again.
The next thing to do might be to run in safe mode for a while. Try to replicate the problem. If you are unable to do so then it is more likely something that is running as either part of the user's profile or something that doesn't run while in safe mode. If it still crashes then it is more likely either a system file or something that does run in safe mode like anti-virus or something.
Unfortunately it doesn't look like the event details has the stack trace. That would narrow things down quite a bit. Otherwise you're going to need a crash dump. This requires some effort but the steps to do so are described here. Once you have a crash dump you can figure out what is causing the failure.
