Do soldering glasses protect eyes from capacitor explosion
If you're working with that sort of stuff and anticipate trouble you may wish to get chemical rated safety glasses eg. ANSI Z87.1–2010 with D3 splash protection. These have side shields as well. 

In some cases (very high power circuits) full face shield protection (or arc flash suits) may be called for. 



This would be somewhat of an extreme precaution for wiring up a typical solderless breadboard with 555s. It's impossible for us to really tell what your situation is. 

Unanticipated venting and explosions are very rare occurrences in most conditions. If you're working with (say) 5V DC circuits, it is exceedingly unlikely anything potentially harmful would happen unless you're doing something really silly like peering at a reversed capacitor from inches away.