BPI QCI cheat sheet

Inspection is a conformity evaluation by observation and judgment, with or without measurement, against specified requirements; it produces a pass/fail or accept/reject decision, not a diagnosis.

Three evidence types drive decisions: visual observation, non-invasive measurement, and destructive or invasive testing; escalation to a higher tier requires a documented reason.

Sampling follows a plan: random or representative selection, defined sample size, and a stated acceptance number; a single critical defect typically rejects the lot regardless of the acceptance number.

Measurement uncertainty must be smaller than the tolerance being judged; the rule of thumb is a test uncertainty ratio of at least 4:1 between tolerance width and measurement uncertainty.

Calibration traceability chain: instrument to working standard to reference standard to national or international standard; an out-of-tolerance instrument invalidates results since its last valid calibration.

Nonconformance handling sequence: identify, document, segregate or contain, disposition (rework, repair, use-as-is, reject), then verify effectiveness of the corrective action.

Inspection points are classified by hold point (work cannot proceed without sign-off), witness point (notify and proceed unless objection), and review point (documentation only).

First article or first-article inspection verifies the process before production volume; subsequent units are verified by surveillance and sampling, not repeated full inspection.

Pressure diagnostics use a reference pressure of 50 Pa (0.2 in. w.c.) for enclosure leakage comparison; a blower-door result in cfm50 is converted to an estimated natural leakage by dividing by roughly 15 to 20.

Normalized leakage is expressed as cfm50 per square foot of conditioned floor area or of envelope area; comparisons are only valid between buildings using the same metric and reference pressure.

Zone pressure testing measures pressure differentials between rooms or between conditioned space and attached zones (garage, attic, crawlspace); a target of roughly 3 Pa or less between conditioned and unconditioned zones indicates acceptable separation.

Duct leakage testing measures total leakage with all registers sealed and leakage to outside with the house pressurized, so leakage-to-outside is the difference between the two results.

Infrared thermography requires a steady-state temperature difference, typically at least 10 °F (5.5 °C) across the assembly, plus low solar loading and low wind; reflective surfaces require a low-emissivity-aware correction or a change of viewing angle.

Moisture measurement: pin-type meters report percent wood moisture content, pinless meters report relative density-based readings, and a reading above roughly 20 percent wood moisture content supports active decay risk.

Combustion safety: ambient carbon monoxide in the breathing zone should be near zero, with any sustained reading above 9 ppm in living space flagged; backdrafting is confirmed by a spillage or draft test under worst-case fan operation.

Airflow verification uses the sensible heat equation Q = 1.08 × cfm × ΔT for air at sea level, and static pressure budgets across the air handler, filter, and coil confirm whether the fan can deliver design airflow.

Scope verification compares installed work to three references in order: the contract or work order, the approved drawings and specifications, and the applicable code or program standard; the most stringent applicable requirement governs.

Quantities are verified by measurement or count against the scope line item; substitutions require written approval before installation, and undocumented substitutions are nonconforming regardless of quality.

Prescriptive versus performance paths must be identified up front; a measure credited on a performance path cannot also be double-counted as a prescriptive allowance.

Insulation verification checks R-value, installed thickness, coverage percentage, and alignment with the air barrier; compressed or gapped insulation fails even when the labeled R-value is correct.

Air sealing verification confirms the air barrier is continuous across transitions, penetrations, and framing intersections, and that it is in contact with or aligned to the insulation boundary.

Ventilation verification confirms the installed fan delivers the design airflow at the measured static pressure, not merely that a fan of the rated size was installed.

Code and standard edition matters: cite the year and section of the adopted code, because requirements for the same assembly change between editions.

Documented equivalency requires an engineer's or program administrator's written determination; field judgment alone cannot approve an alternative material or method.

A defensible report records what was inspected, the standard or specification used, the method and instrument, the result with units, and the disposition; missing any of these makes the finding contestable.

Photographs must be dated, identified by location and orientation, and tied to the specific finding they support; an unlabeled photo is not evidence.

Records must be traceable: unique report identifier, inspector identity and credentials, date and time, and revision history showing what changed and why.

Instrument records include serial number, calibration date, and calibration due date; results from an instrument past its due date are flagged, not silently accepted.

Corrective action closure requires objective evidence of re-inspection or retest, not a verbal assurance from the installing contractor.

Confidentiality and data handling: client information is disclosed only as authorized by the program agreement, and report retention follows the program's stated retention period.

Program compliance documentation typically includes eligibility verification, signed contractor and client acknowledgments, pre- and post-installation test results, and invoice reconciliation against verified scope.

Conflict of interest and independence: an inspector who has a financial interest in the contracting firm's outcome must disclose it and be recused from the final determination.