In one of my EDC's (I have several I can choose from, because it's fun in life to mix things up a little, lol) I've got a pealess metal whistle clipped on to my black SAK Compact model, and with that a black Photon.

And in a hand-made pouch I threw together, I've got another pealess whistle I have from some type of a convention, along with a locking-blade SAK, a flint/steel, compass, and some petroleum jelly/cotton balls in a baggie.

I've never had the need to blow on them in an emergency but they're there for that purpose should the need arise. And for me that's all that matters.