What regulation defines applicable civilian tech certs for the PPW?

After searching high and low, I've got my hands on my EMT-B cert and my BLS card (expired). However, I keep seeing folks say that tech certs are only applicable if your MOS is pertinent to the cert. I'm MI, not medical, so this proposes a problem.
I wanna read it for myself, so if anyone can point me in the right direction to the doctrine, that would be great. I need to know if my former education is still valid or if I should let it go and accept the Army doesn't care.