Around the World, I go! | Riddle #6

Howdy, friends!  It has been a few weeks since I last did a riddle, so lets see who can wrap their minds around this little teaser.  If you think you have the knowledge, put your answer in the comment section below.

Here you guys go:

I am sent around the world,

Although people usually don’t ask for me,

I help protect the unprotected from unintentional harm,

I do not breath, but I use air,

With a sudden noise, it signals my demise.

What am I?

Do you know what it is?  This riddle took a little bit of thought to create, but it is a riddle, none the less (even if it is lackluster).

Have a great week, everyone!  I should be able to write more often then I have for the last couple weeks.  By the way, my last post “what I missed about childhood” did pretty well, even though I had been gone for over a week.  So thanks for your support, and I will see you later!