How do you calculate Device History Record completion time?

Divide entries per lot by the entry rate, then add the review allowance. With 45 entries at 1.5 entries/min the base is 30 minutes; a 25% review allowance brings the total to 37.5 minutes per lot.

What is a good DHR completion time per lot?

There is no universal target, but under 30-45 minutes for a routine lot is healthy for paper records. The 37.5-minute example is typical; electronic DHRs often cut this by half through auto-population and built-in checks.

Why add a review and approval allowance?

Raw data entry is only part of the work — a QA reviewer must check completeness, verify sign-offs, and approve release. The 25% allowance reflects that oversight, adding 7.5 minutes to the 30-minute base here.

How can I reduce DHR time?

Increase the entry rate with electronic records and dropdowns, reduce redundant entries, and design right-first-time forms to shrink the review allowance. Each lever moves a different term in the formula.

Does this include deviation and exception handling?

No. The flat allowance covers routine review only. A single deviation or missing signature can add far more time than the percentage assumes, so treat the result as a best-case baseline.

DHR vs DMR — what is the difference?

The Device Master Record (DMR) is the recipe and specification for the device; the Device History Record (DHR) is the as-built proof that a specific lot followed that recipe. This calculator times the DHR.

MedTech Manufacturing calculator

Device History Record (DHR) Time Calculator

Device History Record (DHR) time is how long it takes operators and quality staff to complete the production record that proves a medical device lot was made per its Device Master Record, as required by 21 CFR 820.184. It captures every data-entry point — process parameters, sign-offs, label reconciliation, and inspection results — plus the review and approval buffer that real records always carry. Production supervisors and manufacturing engineers use it to size documentation labor, set realistic lot-release timelines, and find where electronic batch records would pay off. It matters because DHR time is pure non-value-added labor that directly delays product release.

What this calculator does

Estimate time to complete Device History Record (DHR) documentation per production lot including entries, review, and approval.
Use this when planning production schedules that include documentation time, justifying electronic batch record (eBR) systems, or estimating QA review backlog.
It converts the number of DHR entries per lot and the entry rate into a base documentation time, then adds a percentage allowance for review and approval.

Formula used

Base device history record time = DHR entries per lot ÷ entries completed per minute
Required device history record time = base device history record time × allowance factor

Inputs explained

DHR entries per lot:
Entries completed per minute:
Review and approval allowance:

How to use the result

Use it when staffing documentation labor, estimating lot-release lead time, or building the business case for an electronic DHR system.
It assumes a steady entry rate and a flat review percentage; complex exception handling, deviations, or missing-data chases can add far more time than the allowance covers.

Current U.S. benchmarks

U.S. manufacturing runs at 75.6% of capacity with new factory orders at $657B per month (Federal Reserve and Census, May 2026).
The U.S. has 8,825 medical equipment and supplies establishments employing about 308,388 workers (Census County Business Patterns, 2023).

Common questions

How do you calculate Device History Record completion time? Divide entries per lot by the entry rate, then add the review allowance. With 45 entries at 1.5 entries/min the base is 30 minutes; a 25% review allowance brings the total to 37.5 minutes per lot.
What is a good DHR completion time per lot? There is no universal target, but under 30-45 minutes for a routine lot is healthy for paper records. The 37.5-minute example is typical; electronic DHRs often cut this by half through auto-population and built-in checks.
Why add a review and approval allowance? Raw data entry is only part of the work — a QA reviewer must check completeness, verify sign-offs, and approve release. The 25% allowance reflects that oversight, adding 7.5 minutes to the 30-minute base here.
How can I reduce DHR time? Increase the entry rate with electronic records and dropdowns, reduce redundant entries, and design right-first-time forms to shrink the review allowance. Each lever moves a different term in the formula.
Does this include deviation and exception handling? No. The flat allowance covers routine review only. A single deviation or missing signature can add far more time than the percentage assumes, so treat the result as a best-case baseline.

Last reviewed 2026-05-12.