The Critical Chain in Action
An animation to understand the critical chain: tasks move along the Gantt, the buffer absorbs delays and recovers with early finishes, and the fever chart fills in alongside.
KairoProject
What the animation shows
The animation follows a simple project on a Gantt chart. As tasks progress, two things happen at once: the schedule changes, and the project buffer reacts.
- A delay on a critical chain task consumes part of the buffer.
- An early finish reduces that consumption: the buffer recovers.
- The fever chart, shown in the inset, fills in as these events unfold.
Why look at the buffer rather than every task
In a traditional schedule, each task carries its own margin, and everyone tries to hit their own date. With the critical chain, protection is pooled into a single buffer placed at the end of the project. The question is no longer whether this task is late, but how much buffer is left to absorb what comes next.
The right reflex
A delay is not a problem as long as the buffer consumed does not bring the project into the critical area. The signal to watch is how fast the buffer is being consumed compared with the progress of the chain.
Reading the fever chart in the inset
The fever chart puts two pieces of information side by side: critical chain progress and buffer consumption. Its colour code tells you when to step in.
- Green zone: buffer consumption is in line with progress. No action needed.
- Orange zone: consumption is speeding up. Time to prepare a response.
- Red zone: too much of the buffer is gone. Act now.
To go further, read the guide on the fever chart explained and the one on critical chain vs critical path.
Frequently asked questions
The delay is absorbed by the project buffer, which gets consumed. As long as some buffer remains, the project end date is not at risk: that is exactly what the buffer is there to protect.
When a task finishes ahead of schedule, buffer consumption goes down. The gain is not lost: it protects the end date against future uncertainty.
The fever chart compares critical chain progress with buffer consumption. While the point stays in the green zone, let the work flow; in the orange zone, prepare an action; in the red zone, act.