Manual bps should be taken BEFORE the ambulance rolls or at a stop. We use nibps, but they fail a lot. If it's not a code 3, there's no reason to not get a manual at the scene. If all else fails, palate.
I literally just passed my practicals and I was scared to death I'd failed it because I did NOT admin 02 on a non hypoxic pt with acute MI and said why I wasn't doing it.... My proctor told me after that he was impressed that I didn't and knew why even though this wasn't a critical fail. ON...
I'm just really learning 12-lead and my experience is limited to ED and one agency... BUT... outside the ed (non-emergent) its all torso.
I've actually been told NOT to put leads on the legs. A lot seems to depend on transport times, and it's very rare for us to have more than 5-7 minutes on...