Firefighters would rotate on outside fire watch during the night, usually in two-hour shifts.
Twenty-minute and two-hour shifts have been used in the past.
It is no joke to do a two-hour shift at that depth.
Mr. Harris is working out a roster of two-hour shifts.
They decided to draw straws and keep watch in two-hour shifts.
Six men locked inside the building, two on patrol at a time, again in two-hour shifts.
But we slept in two-hour shifts, because the cell was too small for 20 of us to lie down together.
They also ordered everyone to work a two-hour shift helping produce the protective gear.
"Okay, you can take the first two-hour shift, starting as soon as the rest of the crew turns in."
He worked in two-hour shifts and then rested for two hours.