MRB Cycle Time

MRB Cycle Time commonly refers to the elapsed time it takes for a nonconforming item, material, or event to pass through the Material Review Board (MRB) process from a defined starting point to a defined end point.

In manufacturing and regulated quality environments, the term is used as a process metric for how long MRB-related decisions take. It usually covers the period from identification or submission of a nonconformance through review, disposition, and administrative closure, depending on how an organization defines the clock. Because start and stop points vary, the metric is only comparable when those rules are clearly stated.

What it includes and excludes

MRB Cycle Time typically includes waiting time, review time, routing time, and decision time associated with MRB processing. In digital workflows, it may also include time spent in status queues such as pending review, engineering input, quality approval, or disposition release.

It does not automatically mean total production delay, total repair time, or customer response time. A part can have a short MRB Cycle Time but still experience long downstream rework or replacement delays. Likewise, production hold time may begin before MRB review starts or continue after the MRB decision is made.

How it appears in operations

This metric is often tracked in NCR, QMS, MES, or ERP-connected quality workflows to monitor how quickly nonconforming material is being reviewed and dispositioned. Common dispositions may include use-as-is, rework, repair, return to supplier, or scrap, subject to the organization’s procedures.

Teams may analyze MRB Cycle Time by product line, defect type, supplier, site, disposition type, or reviewer group to understand where review queues or handoff delays occur.

Common confusion

• MRB Cycle Time vs. NCR Cycle Time: NCR Cycle Time may cover the broader nonconformance record lifecycle, including containment, investigation, corrective action, and closure. MRB Cycle Time is narrower and focuses on the review and disposition portion.

• MRB Cycle Time vs. rework turnaround time: Rework turnaround measures execution after disposition. MRB Cycle Time measures the decision path leading to that action.

• MRB Cycle Time vs. lead time: Lead time usually refers to the end-to-end time to produce or supply something, not specifically the nonconformance review process.

Why definition discipline matters

Organizations often define the start of MRB Cycle Time differently, such as when a defect is detected, when an NCR is opened, when the case enters MRB status, or when all required evidence is complete. The endpoint may be disposition approval, release to execution, or formal record closure. For that reason, the term is most useful when paired with a documented calculation rule.