Outside-air delivery among the 65,991 units with ventilation data; each square represents 1% (about 660 units)
Source: CalSHAPE assessment data; data reflect conditions at time of assessment, 2021–2024. Combines units failing the original (V1) protocol’s outside-air delivery test with current (V2) protocol units that had a documented reason the outside-air requirement could not be met. The two protocols measure the shortfall differently, so the combined share is an approximation; see the methods panel.