My nights are 15 hours though. 
I did shift work all of my working life and legally we had to have a clear 11 hours rest time between shifts, so a maximum shift of 13 hours.
On some jobs you can sign away that right, but we were bound by the rules. 
When I did the 6-2, 2-10, 10-6 shifts, we were sometimes asked to cover for someone who hadn't turned up, so a 16 hour shift. You would get time and a half for the second 8 hours and, because you had to turn up again 8 hours later for your normal shift, time and a half again. You can manage it when you're young, I'd have no chance now.
Pah .....!
I trained and worked in the Steel Mill at Ravenscraig Steel Plant covering the same shift pattern as yourself for some years .
What you describe was a "doubler " where you stayed on to cover your absent relief . Also ,The rules were that you could "claim " the shift if he was over 60mins late .
That was a fairly common event in the 70's .
The more uncommon , but not unknown , was the " Ghoster " where if you were unlucky or lucky depending on your viewpoint , and your relief and the relief that followed did not turn up you had to stay on for 24 hours .
I had this occur twice in my years at the plant and indeed one of them followed two doublers in one week ......
I can vividly recall being awakend by two Police officers after a member of the public reported me slouched over the steering wheel after I fell asleep in a car park after stopping for an errand on the way home .
In the event of a Ghoster the management were by the third shift aware of your situation and you were given 24 hours off to recuperate .
Payment was time and a half for the 8-16 hours and double time for the 16-24 hours .
It was rough because my/our responsibilities were the Process and Control Instrumentation over the Strip Mill and you could not just hide in a corner so by the end of the 24 hours you really were at a point of hallucinating .
Health and safety .........nah we never needed that mate ......
