Archive for January, 2010

Staffing on 4-Crew vs 5-Crew Systems

January 13th, 2010

How do staffing, vacation, training and relief work on 4-crew vs 5-Crew systems?

4-Crew vs 5-Crew

4-Crew vs 5-Crew

The image above shows 2 schedules: a 4-crew system in the top schedule and a 5-crew system in the schedule below.

If we assume that the group scheduled here consists of 60 employees, the 4-crew system works out to:

  • 15 employees per crew
  • On any given day there are 15 employees scheduled for the D12 shift, 15 employees for the N12 shift and 30 employees are scheduled to be off work.

A 5-Crew system with the same 60 employees works like this:

  • 12 employees per crew
  • On any given day there are 12 employees scheduled for the D12 shift, 12 employees for the N12 shift.
  • Mon through Fri 12 employees are scheduled for the D8 shift and 24 employees are scheduled to be off work.
  • Sat and Sun 36 employees are scheduled to be off work.

The difference between the two systems is the way that relief coverage is provided.

In the 5-crew system the 12 employees on the D8 shift provide coverage for any absences. If no absences occur the 12 employees can be trained or assigned to special project work. Often employees are encouraged to take their personal holidays during this 5th week.
Since the 5th week is often scheduled as day week, it can be challenging to reschedule employees on short notice to cover unscheduled absences on the N12 shift or the weekends.

In the 4-crew system there are 3 additional employees on shift at any day and up to 3 absences per shift can be absorbed without calling in other workers on their days off on all 7 days of the week. Scheduling training can be more challenging in the 4-crew system. Employees may have more flexibility to take personal holidays since there is no dedicated “extra” week.

In the end you need the same number of employees to cover all positions, absences, and training hours in a 4-crew and a 5-crew system. In a 4-crew system each crew should consist of more people than there are positions in order to absorb absences and training. In a 5-crew system each crew can be staffed to the number of positions and each week one of the 5 crews is responsible for relief coverage.