Check out this cobra video....

Nitrous is totally safe if used properly & as long as you don't get carried away with putting in bigger jets, etc. Pretty much all systems these days have a fuel pressure safety switch which shuts off the flow of nitrous if the volume of incoming fuel, or the fuel pressure drops too low. So they are almost fool proof as long as you upgrade your fuel system. Just make sure that you have plenty of fuel, one or two steps colder spark plug & retard the timing 2-3 degrees for every 50hp of the shot you are running and you're good to go. An aftermarket ignition is a good idea too. That guy with the Cobra had to be running a big shot &/or didn't take the necessary precautions when using nitrous. You might not send your intake through the hood...but engine damage can happen to supercharged or turbo cars too, just as easily IMO.