Fermentation Explosion

I went out last night, leaving my one day old bucket of beer fermenting in my room. It was an imperial pale ale, bubbling like crazy with a little beer coming out of the airlock, but when i came home that night, the lid was blown off and it looked like a wort hand grenade went off in my room, with chunks of wart plastered to everything.
im wondering:
A: why did this happen?

B: how do I make sure it never happens again?

C: is my beer ruined because the lid was blown off for "X" amount of hours (one long night of drinking).

I cleaned the lid and the airlock with water, replaced everything and now it is bubbling again, I just want to know if i should dump this batch out because its ruined or not.

thanks

Welcome to HBT!
Your beer is not ruined. You ceiling may be but not your beer. It happened because you have some really good fermentation going on and your airlock got clogged with krausen. Krausen, as you discovered, does not like to be confined without an outlet.

Next time rig up a blow off tube so the krausen has a place to go.

I wouldn't dump it. It will probably be okay.

As to the explosion something plugged so you built up pressure. This is why people use blow off tube for very active fermentation (or always as is my practice). Beer in the airlock is a sure indication you need a blow off tube IMHO.

So for next time be sure you know how to rig a blow off on your set up.

Happy cleaning.

Don't worry!

It'll be OK, and will probably turn out just fine!

Take the airlock off...fit a couple, or three, feet of plastic tubing from the grommet in the lid, or the stopper in the carboy, to a jug or bucket with a few inches of water in it, and it will not happen again.

Assuming that your tubing is big enough to pass any solid chunks of hops, grain, etc., that may be in your wort.

Pogo