Intry Verified receipt
Is the Intry Duct Size Calculator accurate?
The provenance receipt for the Intry Duct Size Calculator: the exact authority its values derive from, the edition they are keyed to, who has final say, and what our automated checks hold them against, rebuilt from their cited source.
The receipt
- Calculated from
- ASHRAE Fundamentals duct-friction model (Darcy-Colebrook) · ASHRAE Fundamentals 21.3.1 equivalent diameter (Huebscher) · Standard manufactured duct sizes (McGill AirFlow / SMACNA) · Advisory design targets (Manual D basis, a secondary's velocity bands). Reused verbatim from the locked engine, never re-written for this page. The documents it rests on are listed in the source receipt on the tool page.
- Edition
- not a code table
- Checked
- Before any release, an automated check runs the locked engine that produces these figures and holds its answers against values written from the source it cites, so a checked number answers to its source and not merely to itself. The check covers the cases someone wrote a check for, not every input the tool accepts: it tells you where a number comes from, and it is not a proof of every value. As of the current build that suite holds 31163 checks, and this page has to clear them too. This is our own deterministic gate, not a third-party audit.
- Runnable
- A reference engine behind the published numbers on this site. Runnable access is offered on the calculators exposed at the Intry MCP endpoint.
- Final say
- A full ACCA Manual D duct design and the equipment's blower data have final say.
Frequently Asked Questions
Is the Intry Duct Size Calculator accurate?
It computes from the sources listed in the source receipt on its tool page, and our automated checks hold its answers against values written from those sources for the cases the checks cover, not for every input you can enter. A full ACCA Manual D duct design and the equipment's blower data have final say. Every figure an Intry calculator computes comes from a locked source module, not hand-typed. 31163 automated checks, one suite for the whole site rather than a per-tool count, re-derive the numbers before each deploy from the tables this site transcribed from the ASHRAE Fundamentals and ACCA Manual D duct-design standards it was computed from. This is our own deterministic gate, not a third-party audit. The per-tool receipt is public at https://www.intrysys.com/verified.