Mean Time Between Interruptions is the simplest vital sign a line has, how long it runs, on average, before something stops it. Across 62 lines we measured a pulse of just 1 minute and 14 seconds. Here's why that number should worry you, and what a healthier one is worth.
Every production line runs, stops, and runs again. Measure the average length of those runs and you have its pulse: Mean Time Between Interruptions. It is the most honest one-number summary of how stable a line really is, and unlike a shift total it can't be flattered by a good hour.
Across the 62 lines in our study, the weighted-average MTBI was 1 minute and 14 seconds. Seventy-four seconds of running, then a stop. Then seventy-four more. That is not a line producing with the occasional hiccup, it is a line trapped in a constant cycle of micro-stops, forced to spend its operational life decelerating or ramping back up, never hitting a steady state.
Performance losses on a fragmented line don't come from a slow machine. They come from a machine that is never allowed to run. MTBI is the metric that makes that visible, where a shift total hides it.
The stable cohort in the study ran at an MTBI of about 3 minutes 27 seconds, nearly three times longer between stops. That is the benchmark worth chasing. On one studied site, moving from the 1m 14s stutter toward that benchmark reclaimed 5.64% of total plant capacity, with no change to the machine's rated speed.
One caution: a raw MTBI can mislead if you ignore the line's stop threshold, the delay before a pause is counted. A lenient threshold can make a chronically stuttering line look calm. That's why MTBI should always be read against the Threshold Exposure Index. Read together, they tell you both how fast the pulse is and whether you can trust the reading.
MTBI is one of the central metrics in the Interruption Whitepaper, and the raw material of the Speed Tax.
Mean Time Between Interruptions is the average length of time a line runs before it is interrupted. A high MTBI means long, stable runs; a low MTBI means the line is constantly stopping and restarting.
At roughly seventy-four seconds between stops, a line never reaches kinetic equilibrium. It spends its operational life decelerating and ramping back up, which caps performance regardless of the machine's rated speed.
Mean Time Between Failures counts breakdowns, the longer stops that get a reason code. MTBI counts interruptions, including the short, high-frequency micro-stops that never trigger a code but do the most cumulative damage.
Yes. A raw MTBI can be flattered or hidden by the line's stop threshold. Always read it alongside the Threshold Exposure Index so you know whether the number reflects reality.