We have 3 hospitals, and a different setup at each hospital.
Hospital A, private hospital. PGY4 chief inhouse nightfloat, does the operating and overseeing, PGY2 midlevel nightfloat sees all ER consults, occasional operating, helps answer intern questions if not busy, and Intern "nightfloat" (which rotates one of the interns from the day teams every week to be this, so its not a dedicated night float, just one week from the month) which cares for all the floor patients, does the 10-20 post op checks a night, etc.
Hospital B, VA hospital, has a PGY2 or 3 which takes care of the "ICU" and oversees the intern, which is on a "nightfloat" system similar to the setup at hospital A, where the intern cares for the floor patients and sees ER consults. PGY5 is chief and is on home call
Hospital C, University public hospital has multiple different teams. Trauma is Q3 for everyone save interns. The 3 teams consist of: Team A is PGY4 and PGY2, Team B is PGY5 and PGY3 rotator from Columbia, and Team C is Trauma Fellow and PGY3. There are also various rotators from ER programs, which if not interns then get put into one of the above teams. Interns do essentially shift work, primarily night shifts, but no set pattern. For general surgery, there is an intern night float (true night float, 1 month assigned rotation of just nights), the midlevel (PGY2/3) takes call at Q3-Q6 depending on how many PGY2's and 3's are currently available for the call schedule (We have prelim 2's and plastic surgery 2's and 3's which get placed seemingly at random onto the teams there is not a standard amount of people covering the 4 teams that feed into this midlevel pool, but always atleast 3, and can be upwards of 5-6). Chiefs of the various services are on home call (which is a PGY5 for General, Oncology, and Vascular, and a PGY3 for thoracic). SICU is Q3, and the SICU has a PGY3, PGY2, and either a prelim2, plastics2, or 2 interns (which I'm not quite sure how the interns in the ICU will work, last year we were just Q3 but with the new hours, thats why it's 2 interns at a time...). There is a trauma attending in house all the time and the Trauma chief will serve as backup for whoever needs it in house as well, but if general surgery operating is to be done, the service chief comes in from home.
So thats how we have not gone to a pure night float system and have managed to stay compliant, or so I believe... not sure on the VA...