What is the origin of "Panama schedule"?
Solution 1:
I just have a hunch here and I don't have a lot to back it up but:
The Panama Canal operates with "3 locks up and 3 locks down per transit" per, the Panama Canal Wikipedia page, on the sidebar.
BMS Central has this helpful chart for visualizing the Panama schedule.
As you can see for each 2 week period, a given team has a set of 3 consecutive days working and another set of 3 consecutive days not working. I believe the Panama part of the schedule comes from the canal having 3 locks up and 3 locks down.
This Reddit thread of people in the Air Force who actually worked these hours mentioned Panama 8s and Panama 12s. Both seem to stick to the all important 3223 and I would imagine have a gap of 3 days off in between the 2s just like the above chart has. Still not a source for why they're called Panamas, but I think this supports my hunch.
Solution 2:
In Comparison of Two Watch Schedules for Personnel at the White House Military Office President's Emergency Operations Center, a 16-page article published in 2015 by the U.S. Defense Technical Information Center (DTIC), the authors compared two different shift schedules to assess their effectiveness. One of these was the "Panama schedule, a slow rotating system of four teams covering two 12-hr shifts each day" (p. 3). Because this is a scholarly research paper, it contains an extensive reference list.
One of the references is James C. Miller's 2006 paper, Fundamentals of shiftwork scheduling, also published by DTIC. This paper describes the Panama schedule in depth and mentions its use by the United States Air Force (USAF) Security Forces.
For example, there is a shift plan used by many USAF Security Forces operations called the “Panama” or “every-other-weekend-off” plan. This plan is presented in more detail in Chapter 4. The shift plan cycle length is 14 days (a multiple of 7) and it uses nominal 12-hr shifts (without overlap; see Chapter 4). The rotation between day and night shifts usually occurs once every 28 days (a “slow” rotation). Working days or nights, you follow this work-rest sequence for each 14-day cycle: 2 days on, 2 days off, 3 days on, 2 days off, 2 days on, and 3 days off. The 3 days on and the 3 days off both fall on Friday, Saturday and Sunday, giving you every other weekend off. (The Fridays “off” during the night shift month should be viewed as recovery days.) Thus, across 364 days (26 of these 14-day cycles), you would have 26 weekends, or 52 weekend days, off per year. That is only half the number recommended by Principle 5. Thus, the plan is quite weak in this regard and you should expect shiftworker complaints about inequity with people with weekday jobs and 52 weekends off per year.
Other online references (forum threads etc.) have also alluded to the schedule's use by law enforcement and security teams.
I've checked various physical books in my local university library in and around the HD 5106 and following sections (Library of Congress classification for Industries / Labor / Hours of labor; Including overtime, shift work, sick leave, vacations), and I've not been able to find any references to Panama schedule, Panama plan, or Panama shift. I think the term may be more recent than the publications I was looking at.
In particular, I examined Colquhoun & Rutenfranz (1980), which is a 468-page collection of scholarly articles about shiftwork. The collection contains descriptions of many different shift schedules, but none of these was named Panama, and more importantly, none of these was the specific 2 on, 2 off, 3 on, 2 off, 2 on, 3 off pattern of 12-hour shifts used by the Panama schedule.
Likewise, Folkard & Monk (1985) contains several chapters about shiftwork, watches at sea, and air crews, but not security. Again, there is no mention of the Panama schedule or one that looks like it.
In all, I examined about 10 books about shiftwork, all published approximately 1955 - 1985, and did not find any mention of the Panama schedule. Many of these books contained graphical depictions to explain various shift schedules, but none of them looked exactly like the Panama schedule.
Theory: The term originated with the military law enforcement, and surfaced into general usage sometime in the 1980s.
References:
- Colquhoun, W. P., & Rutenfranz, J. (1980). Studies of shiftwork. London: Taylor & Francis.
- Folkard, S., & Monk, T. H. (1985). Hours of work: Temporal factors in work-scheduling. Chichester [West Sussex]: Wiley.