March 8, 2026 · Engineering Update · Change-Control Note
Material Substitution Risk Checklist Introduced
The substitution checklist defines when material change should start and how release risk should be judged with evidence.
When sourcing alternatives are proposed, teams now evaluate compatibility, odor, color drift, and mold-fit impact in one standard checklist before approval.
When To Start A Substitution Review
Supplier shortage, cost shock, or compliance updates can trigger substitution, but each trigger must be documented with expected impact.
If interface fit or odor sensitivity is involved, substitution should be treated as a structural risk item, not only a purchasing item.
Release Gate Should Include Three Views
A practical gate includes: compatibility test, appearance stability, and process repeatability in pilot lot.
Release reports should compare old and new material side by side to support buyer approval efficiency.
Substitution Gate Checklist
1. Document trigger reason and impact scope.
2. Compare old and new materials in one report.
3. Complete pilot repeatability verification before release.
Source Note
Prepared from Yaoshun toy, tube, and equipment project practices plus public product modules. Snapshot date: April 12, 2026.