How do you calculate change notice review workload?

Divide the number of notices by the review rate to get base hours, then multiply by the allowance factor. For 120 notices at 12 per minute the base is 10 hours, and a 10% allowance yields 11 required hours.

Why add an allowance on top of the base time?

Base time assumes continuous reviewing; the allowance covers setup, pulling supporting documents, coordination emails, and interruptions. A 10% allowance turns 10 base hours into 11 realistic hours.

What is a realistic SCN review rate?

It varies widely by change complexity. The 12-per-minute figure here reflects fast triage of simple notices; detailed engineering reviews of a form-fit-function change run much slower, so calibrate the rate to your mix.

How do I use this to staff the review queue?

Divide the required hours by available reviewer hours per period. Eleven hours is under two shifts for one reviewer, but a spike of hundreds of notices quickly justifies a second person.

Base time vs required time — what's the difference?

Base time is pure review at the stated rate (10 hours); required time adds the allowance for real-world overhead (11 hours). Always staff to the required figure.

Should complex and simple notices use the same rate?

No. Averaging masks the risk that a few complex PCNs consume most of the time. If your mix is uneven, run the calculator separately for simple triage and detailed reviews.

Supplier Quality, Development & Audits calculator

Supplier Change Notice Workload Calculator

Supplier Change Notice (SCN/PCN) workload is the reviewer time needed to assess and disposition change notices before altered parts reach production. SQEs and quality engineering managers use it to staff the change-review queue so PCNs don't pile up and force uncontrolled changes onto the line. The calculator converts a backlog of notices and a per-notice review rate into base hours, then adds an allowance for setup, coordination, and inevitable delays. It turns a vague 'we're drowning in change notices' into a defensible hours figure for planning.

What this calculator does

Estimate supplier change notice workload for supplier quality, development and audits using production-ready inputs so teams can plan labor hours, schedule the work, or check whether the job fits the available shift time.
Use it when supplier change notice workload in supplier quality, development and audits is changing rate or allowance and you want to see the impact.
It converts a count of change notices and a review rate into required reviewer hours, including a setup and delay allowance.

Formula used

Base supplier change notice workload time = supplier change notice workload workload ÷ supplier change notice workload completion rate
Required supplier change notice workload time = base supplier change notice workload time × allowance factor

Inputs explained

Change notices to review this period:
SCN review throughput per reviewer:
Setup, handling, and delay allowance:

How to use the result

Use it for staffing the SCN/PCN review queue, sizing an audit or campaign, or forecasting a change-heavy quarter.
It assumes an average review rate; a batch of complex safety-related PCNs will take far longer per notice than the average implies.

Current U.S. benchmarks

U.S. manufacturing runs at 75.6% of capacity (Federal Reserve, May 2026). New factory orders are up 2.3% year over year (Census).

Common questions

How do you calculate change notice review workload? Divide the number of notices by the review rate to get base hours, then multiply by the allowance factor. For 120 notices at 12 per minute the base is 10 hours, and a 10% allowance yields 11 required hours.
Why add an allowance on top of the base time? Base time assumes continuous reviewing; the allowance covers setup, pulling supporting documents, coordination emails, and interruptions. A 10% allowance turns 10 base hours into 11 realistic hours.
What is a realistic SCN review rate? It varies widely by change complexity. The 12-per-minute figure here reflects fast triage of simple notices; detailed engineering reviews of a form-fit-function change run much slower, so calibrate the rate to your mix.
How do I use this to staff the review queue? Divide the required hours by available reviewer hours per period. Eleven hours is under two shifts for one reviewer, but a spike of hundreds of notices quickly justifies a second person.
Base time vs required time — what's the difference? Base time is pure review at the stated rate (10 hours); required time adds the allowance for real-world overhead (11 hours). Always staff to the required figure.

Last reviewed 2026-05-12.