There is no way of doing it other than using an oscilloscope to check for clipping (or in rare cases some amps have a clipping indicator).
Volume control position is completely irrelevant as is any sort of display on the amp. A SPL meter is also useless for this.
The most common problem is tweeters blowing and this is usually because the amp is not powerful enough for the volumes being used and is clipping. This causes ultrasonic distortion at a power level which will blow the tweeter. At such high frequency all this distortion is fed to solely the tweeter and a tweeter on it's own will usually only handle say 10W even if the speaker says "200W power handling" on the back. This is why a clipping indicator can be useful.
The other speaker blowing issue is the more intuitive "too much power". This can blow any drive unit but bass drivers are the most likely. As pointed out by others above, there is not much you can do beyond common sense and having bit of "mechanical sympathy" by listening out for a speaker under distress, "end stops" being hit by woofer excursion etc...
It is generally far safer to use an amp rated at say 200W into a speaker rated for 50W than to use an amp of 20W into a speaker rated at 200W. Yes this is counter intuitive... but correct.
An add-on clipping indicator is not particularly difficult or expensive to make but the problem is it must be adjusted for a particular amp which needs test gear...
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