Yeah, they're safe. You can search some previous threads on this. They don't explode. At most they will vent rapidly - think of a fire extinguisher. Might make a loud noise and make a bit of a mess, but no explosion, and no dangerous levels of CO2.
Take precautions such as restraining the tank during transit, don't leave it in the car over summer, and restrain it under your stand, and you should have nothing to worry about.
Take precautions such as restraining the tank during transit, don't leave it in the car over summer, and restrain it under your stand, and you should have nothing to worry about.