What is a device history record?

The production record for one lot: build steps, components, tests, deviations and release signatures. It is the objective evidence that the lot was made to its specifications. Section 820.35 applies ISO 13485 Clause 4.2.5, so entries must be legible, identifiable and retrievable.

Why does review and approval take longer than entry?

Reviewers read the whole record, not only the newest entry, so their time grows with the record's length rather than the operator's typing speed. Corrections and missing values add follow-up on top of the reading.

Where does the entry rate come from?

From record timestamps in an MES or eQMS, or from timing a full lot with a stopwatch. Use a real lot with its interruptions, because a rate measured on a clean demonstration is faster than production.

Can one shift finish a lot's record work?

Compare total minutes against the shift length. When the total is under the shift, the remainder is buffer for corrections. When it is over, the record sits unfinished and release waits, so plan the review into the next shift.

MedTech Manufacturing calculator

Device History Record Time Calculator

Find how long device history record work takes per lot and whether it fits inside a shift. You need entries per lot, an entry rate, a review allowance and the shift length.

What this calculator does

Minutes to complete and approve a lot's device history record, and the share of one shift that work takes.

Formula used

Base documentation minutes = DHR entries per lot ÷ entries completed per minute
Review and approval minutes = base documentation minutes × allowance percent ÷ 100
Total completion minutes = base documentation minutes + review and approval minutes
Share of shift = total completion minutes ÷ shift minutes

Inputs explained

DHR Entries per Lot: Records per lot: build steps, components, tests and release signatures.
Entries Completed per Minute: Typical completed entries per minute, from a time study or record audit.
Review and Approval Allowance: QA review and approval time as a share of entry time.
Shift Minutes: Shift minutes available for record completion and review.

How to use the result

Best suited to sizing DHR work for a new line, deciding if review needs a second reviewer, fitting record completion into one shift.
Deviations, missing data chases and corrections can add more time than the allowance covers. A record finished across two shifts needs both shifts added together and split carefully.

Current U.S. benchmarks

U.S. manufacturing runs at 75.7% of capacity with new factory orders at $663B per month (Federal Reserve and Census, Aug 2026).
The U.S. has 8,825 medical equipment and supplies establishments employing about 308,388 workers (Census County Business Patterns, 2023).

Common questions

What is a device history record? The production record for one lot: build steps, components, tests, deviations and release signatures. It is the objective evidence that the lot was made to its specifications. Section 820.35 applies ISO 13485 Clause 4.2.5, so entries must be legible, identifiable and retrievable.
Why does review and approval take longer than entry? Reviewers read the whole record, not only the newest entry, so their time grows with the record's length rather than the operator's typing speed. Corrections and missing values add follow-up on top of the reading.
Where does the entry rate come from? From record timestamps in an MES or eQMS, or from timing a full lot with a stopwatch. Use a real lot with its interruptions, because a rate measured on a clean demonstration is faster than production.
Can one shift finish a lot's record work? Compare total minutes against the shift length. When the total is under the shift, the remainder is buffer for corrections. When it is over, the record sits unfinished and release waits, so plan the review into the next shift.

Last reviewed 2026-10-01.