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How to run a first-article inspection and mock-up

A first-article inspection is a complete, feature-by-feature check of the first item off a run before the rest is allowed to proceed. A mock-up is its site-built cousin: a full-scale sample of a repeating assembly, approved before production, that becomes the workmanship standard. Both share one idea — inspect one thing in full while a mistake is still a single mistake, not a whole run of them. This guide covers running both and turning the approved sample into the reference for the work that follows.

For QC managers, superintendents, and fabricator liaisons setting the standard for a fabricated item or a repeating field assembly before full production.

Step by step

  1. Decide whether it's a first article, a mock-up, or both

    Use a first article for fabricated or manufactured items — the first weldment, the first panel. Use a mock-up for repeating site assemblies — an exterior wall section, a masonry panel, a bathroom, a window-and-flashing detail. Some scopes need both.

  2. Pull every requirement the sample must meet

    Assemble the drawings, specification, approved submittals, and tolerances that apply. A first article is checked against all of them, item by item — every dimension, material, and requirement, not a spot check.

  3. Build or produce the first item under production conditions

    The sample only means something if it's made the way the real work will be — same crew, methods, materials, and equipment. A mock-up built by the A-team with special care sets a standard the production run can't hit.

  4. Inspect it feature by feature and record each result

    Go requirement by requirement: state the requirement, the measured or observed result, and the disposition. This item-by-item record is what makes a first article different from a general once-over.

  5. Walk it with the parties who accept it

    Bring the architect, owner, and engineer to the mock-up or first article, mark it up, correct it, and get formal acceptance. Their sign-off is what converts a sample into the standard.

  6. Establish the approved sample as the reference

    Once accepted, the sample stops being a sample. Keep the mock-up standing on site or the first article on file as the benchmark, and measure the initial phase of the real feature against it.

  7. Carry the record into the turnover package

    The documented first article or approved mock-up travels with the fabricated or installed work as proof the standard was set and met. It settles later 'is this acceptable' questions with a physical answer.

What gets missed

  • Building the mock-up to a higher standard than the production crew can realistically repeat, so the real work looks like a failure against it.
  • Sampling a few features of the first article instead of checking every requirement, which is the whole point of a first article.
  • Tearing down or losing the approved mock-up, so there's nothing to measure the initial phase against.
  • Producing the full run before the first article is accepted, so a bad detail is already reproduced everywhere.
  • Skipping the architect's and owner's formal acceptance, leaving 'acceptable' undefined when the argument comes later.

Questions people ask

What's the difference between a first article and a mock-up?
They share the same intent — set the standard on the first one. A first article is a full inspection of the first fabricated or manufactured item against every requirement; a mock-up is a full-scale physical sample of a repeating site assembly, built and approved to become the workmanship reference.
How does a first article relate to the initial phase inspection?
They're closely related. The initial phase inspects the first completed portion of a feature to set the benchmark; a first article does the same for fabricated items, and an approved mock-up or first article is often exactly what the initial phase is measured against.

Terms worth knowing

Checklists that make this a one-tap job

Free, field-ready checklists, each with the photo every item needs before it can be submitted.

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Related guides

Reading the steps is one thing. Proving you walked them is the job.

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