I stumbled across this article today on which explains how caffeine works in our brains and why it does what it does.
http://gizmodo.com/5713564/what-caffeine-actually-does-to-your-brain
Original source: http://www.gizmodo.com
I stumbled across this article today on which explains how caffeine works in our brains and why it does what it does.
http://gizmodo.com/5713564/what-caffeine-actually-does-to-your-brain
Original source: http://www.gizmodo.com
Sometimes it is sufficient to schedule a minimum of employees during the night and then staff up during the day time.
Maintenance departments can be an application of this concept. Coverage needs to be provided around the clock – but many projects and improvements are usually done during the day time.
An easy way to achieve this could be the following:
One could divide the existing employees into 6 teams instead of the standard 4 teams normally required to staff around the clock. For an example 2-3-2 12-hr schedule the 6-week/6-crew cycle could then look like this:
In the example above the 6-week cycle results in 2 crews on Days for every 1 crew on Nights 7 days a week. For each individual it would mean 4 weeks on Days for every 2 weeks on Nights – which may make this concept more attractive than balanced staffing as well.
How do staffing, vacation, training and relief work on 4-crew vs 5-Crew systems?
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:
A 5-Crew system with the same 60 employees works like this:
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.
Circadian’s work with the trucking company Dupre Logistics was recently featured in a documentary shown on Australian TV. The program “Dead Tired” is also available on DVD.
Enjoy the excerpt of the program about Circadian’s work.
Probably the most asked question in our industry schedule projects is: What is the best schedule out there?
Understandably many managers would like to pick a proven schedule that is sanctioned to be “the best” and simply implement that. Case closed. Next.
In reality the case is not that simple. Our answer to the best-schedule question is: “There is no such thing as a best schedule. The best schedule for your operation is a schedule that works best for your operational requirements and the social preferences of this specific group of employees at your site at this time.”
In other words, a schedule that works fine at the place down the street may not work well in your environment. And even within the same corporation there can be different social preferences from site to site. No two demographics are the same, and different people are at different stages in their life and want different things out of a schedule.
The following is an example of a schedule project that demonstrates this point:
In general we found that the way a schedule is implemented has a big impact on how well it will perform.
Every year CIRCADIAN invites managers of shiftwork operations to tell us about their operations in an online survey. The information is used to identify trends and a snapshot of the current state of the shiftwork world.
One of the questions we ask is: “What shift length is worked by the majority of your shiftworkers?”
Below are the answers of about 400 facilities from the last survey:

What shift length is worked at your facility?
As the chart above shows 8s and 12s are about equally common followed by combinations of 8s and 12s. We see 10-hr shifts used mostly in operations that do not run 24 hours a day, e.g. food manufacturing and processing which requires a daily shutdown of production and cleaning of the equipment.
A big source of concern for managers and employees when entertaining the idea of 12-hr schedules is the question of how absentee shifts will be covered in both systems.
Coverage on 8-hr schedules normally means that a person from the previos shift has to stay 4 hours beyond their 8-hr shift and a person from the following shift has to come in 4 hours early. Together the two people cover the 8 hours left uncovered by the absence. Both people were already schedule to be at work that day anyway.
The image below shows an example of a typical 8-hr schedule with 4 crews and 4 people per crew. If employee #5 reports sick on Wednesday and Thursday (red), one employee of the day crew has to stay 4 hours later and one employee from the night crew has to come to work 4 hours early (orange).

Coverage on 8-hr schedules
On a 12-hr schedule it is not feasible to work half of another shift to cover for an absent co-worker. Instead someone from a crew that was scheduled to be off work that day has to fill the shift.

Coverage on a 12-hr schedule
As shown in the example above only one person has to work the absent shift on Wednesday and Thursday. In the example 3 employees from the day crew keep their day off and the 4 people from the night crew were also unaffected by this change.
So how do companies manage this system?
As with any problem, there are various solutions. What we often see with clients is a voluntary sign-up system where employees can make themselves available to work overtime on their scheduled days off.
Some companies develop call-out schedules which then designate which individual is responsible for vacant shifts on any day. Obviously not all off days are scheduled as cover days – only enough to provide coverage for expected levels of absenteeism.
Both systems work and we have seen clients that utilized both systems in different areas of the same plant. Which system can work in your environment depends a lot on your workforce and the managers in charge of the areas.
One question that is often raised and the cause of confusion is the question about overtime on 8s vs 12s.
Will the amount of overtime change when changing from 8s to 12s?
The answer is: It depends on what is driving your overtime on the current schedule.
If your absenteeism is driven by a mismatch between the social needs of the employees and the schedule pattern, a schedule pattern that involved the employees in the selection can result in a reduction in absenteeism and therefore overtime.
On an 8-hr schedule that is designed to cover the 168 hours of the week, one would typically need 4 people per position – or 4 crews for the entire operation. Each person/crew works an average of 42 hours a week (168 hours / 4 people). This average is achieved by working 40 hours a week 3/4 of the time and 48 hours per week 1/4 of the time.

8-hr schedule
The schedule in the graph above shows a typical 8-hr schedule. On any given weekday 3 out of 4 people/crews are scheduled to work. Each person/crew has 7 days off per 28-day cycle.
During the entire year, each crew is scheduled to work 273 days/shifts for a total of 2184 hours. Each crew is schedule to be off work for 91 days per year.
On a 12-hr schedule that is designed to cover the same 168 hours of the week, one also typically needs 4 people/crews. Each person/crew is still scheduled to work an average of 42 hours per week (168 hours / 4 people). On a 12-hr schedule this is achieved by working 36 hours a week 1/2 of the time, and 48 hours per week the other 1/2 of the time.

12-hr schedule
The schedule in the graph above shows an example for a 12-hr schedule. On any given weekday 2 out of 4 people/crews are scheduled to work. Each person/crew has 14 days off per 28-day cycle.
During the entire year, each crew is scheduled to work 182 days/shifts for a total of 2184 hours. Each crew is scheduled to be off work for 182 days per year.
For both schedules, Sunday 7 AM (start of day shift) was used as start of the pay week.