I had to do the same thing this summer. What I did was split the bombing into a 2 day event. One the first day, I did the basement (which is where my bed room is). I moved my snake upstairs, and placed in him in a room at the far end of the house with all the windows opened, and a placed a towel over his lid. I then sealed off all the vents with plastic and duct tape and ran 2 fans blowing air form the room out the window.
I then did the upstairs the second day, and pretty much repeated the process above. The snake was fine.
On a different note however... I found bug bombs do nothing for fleas. Within 48 hours, all the fleas were back. After doing some reading, I found out that to effecitvely kill the flea population, you have to use an agent that inhibits the development of the eggs (apparently the dang things are near indestructible).The stuff I ended up using was called Spectracide. It can be bought at Wally World and is safe for pets once it drys.
In addition fleas can live under your carpet and survive off of the dead skin and hair. So a major cleaining of your carpet is also needed. I ended up having to use a heavy duty shop vac. If you have tile floors, your best bet would be to bleach the crap out of it.
Either way, if your using a pesticide, and/or alot of bleach, its best to keep all of your pets in an area away from cleaning with plenty of ventilation and clean water.