Pretty much what Moosebunk said. I did 8 hr shifts(9 days on-6 days off)1972-77 for about the first 5 years, then 12hr shifts from 77 to about 2007. Some were 3D-2N, 4 off, 2D-3N, 5 off. Unless all the others at home understand your need for sleep in the daytime, it can be holy hell. Fortuntely back then the kids were good about it. When I got to straight days about 5 years ago, it was unbelieveable, bacon and eggs at the right time of day, poop at the right time of day, you get the picture. Your body will hate you..often.