# Risks

| ID | Category | Risk | Verification test | Mitigation |
| --- | --- | --- | --- | --- |
| ADF-AC-01 | Acoustic | Duct/window geometry does not speak below high breath pressure | First-sound test before drilling holes | Keep block removable; tune windway/window first |
| ADF-AC-02 | Acoustic | Tone-hole formula misses because effective open point shifts | Drill undersize and log final diameters | Tune from foot upward and update design table |
| ADF-ST-01 | Structural | Labium edge chips in hardwood | Cut window coupon first | Use PVC proof body and sharp tools |
| ADF-ER-01 | Ergonomic | Hole spacing is too wide on low member | Paper reach test and mock grip | Start with G4 before lower tarka body |
| ADF-SU-01 | Supply | Nominal PVC ID differs from formula assumptions | Measure ID at intake | Recalculate length with measured bore |
| ADF-FI-01 | Fit/finish | Removable block leaks or shifts after reinstall | Tuner before/after block reinstall | Shim/wax block; reject loose fit |