First things first: what is a shift? The definition of the word shift will change according to the environment you are in. For some, it represents the span of a day where everyone is scheduled to work at the same time (the day shift in a manufacturing shop). For others, a shift represents the start and end time of continuous work presence for one employee. In this section, the shift means the latter: a continuous work presence that has a commitment from the employee to be ready for work until the end of the presence.
The constraints surrounding are measurable either in time or in occurrences:
- Minimum shift duration: When an employee comes in to work, their presence will be for a minimum time. You would not ask someone to come in just for 15 minutes to clean the floor and then go home. You’ll have to determine the best minimal shift duration that makes sense for your business (some are as low as 3 hours for part-time employees).
- Maximum shift duration: Obviously, you can’t ask someone to be present at work for eternity. They will eventually have to go home and sleep. Although some environments schedule employees for up to 36 hours (doctors in a hospital have very long shifts), this maximum rarely surpasses 12 hours. Some businesses give high bonuses when the shift needs to exceed 12 hours. Other areas are controlled by law (for example truck drivers can’t drive for more than 10 hours in a row) and impose constraints for public safety. All in all, you’ll need to establish a maximum.
- Maximum duration before a break: An employee will require a coffee break at some point. So within a shift, you need to define how long someone can work without a break. Note that breaks are not necessarily scheduled.
- Minimum break duration: A two-minute break won’t do. There is a minimum amount of break is required which is usually around 10 to 15 minutes.
- Maximum duration doing the same activity: Some activities are harder to do than others. In order to reduce the strain on employees and also reduce the risk of injuries, some organizations have established maximum durations for the same activity. This applies mostly to manufacturing areas where some jobs are physically demanding.
The constraints listed above are imposed by the fact that humans need rest and common sense requires keeping them safe from injury and productive for the business.
Other constraints about the shift can be driven by the business to keep the employees productive:
- Maximum break duration: In order to keep employees productive, you need to split the total break time into multiple breaks. Having long breaks have showed that employees come back less productive and take more time to get back up to their regular productivity level. How many times have you gone out for a long lunch and come back feeling drowsy, no matter what you ate?
- Maximum number of different activities in a shift: There is a limited number of things an employee can do within a day. If too many activities are scheduled, that employee will become non-productive at some point. The mental change required to start a new activity makes that activity non-productive for the first minutes until the brain gets into gear. Too many activities simply multiply this non-productive time.
- Minimum activity duration: Although this constraint could be seen as reaching the same goal as the previous one, it’s actually listed for a different reason. An activity that requires a long time to setup or longer preparation time will be constrained by a minimum duration. You wouldn’t want to repeat that long non-productive time too many times so you would want to leave an employee on that activity as long as possible.