Curious about AFCI

[safarisailor]

The other day I was reading about how many (most?) electrical fires are from arc faults (loose connection causing arcing, or broken wires, etc...), and wondered why there isn't a device to detect it. So I googled, and learned about AFCI (arc fault circuit interrupters).

Apparently these are being installed in houses, specifically in bedrooms.

I haven't been able to find any information about AFCI with DC circuits. I couldn't find any vendors either.

Can anyone with more electrical-systems knowledge than I have tell me if AFCIs can work with DC? And if yes, considering DC electrical arcs cause a very large percentage of boat fires, why isn't this a more common device on boats?

Thanks much!