Typical air vs. spike days
- Annual average PM2.5 (8.88 µg/m³) reflects usual daily exposure.
- Worst-day peak PM2.5 (37.16 µg/m³) is what filtration must handle during bad-air events.
Sections below reference one or both metrics on purpose — that is how HVAC vs. portable guidance differs for Campbell without contradicting EPA-aligned thresholds.
Local Allergen and Dust Load
Seasonal loads in Campbell are driven by the diverse vegetation of the Santa Clara Valley. Pollen from oak, sycamore, and various grasses creates a heavy biological load that can quickly saturate thin fiberglass filters. Areas near the Los Gatos Creek Trail contribute to high seasonal counts that often peak in the spring and fall. These allergens act as a physical pre-filter on your HVAC system, clogging the media and forcing the motor to work harder. In this environment, the filter's job is to manage both the microscopic PM2.5 and the much larger, high-volume pollen grains that circulate through the valley during peak bloom periods.
Technician's Filter Recommendations
Given the PM2.5 peak of 37.16 µg/m³ and the ozone spike of 0.0795 ppm, I recommend a MERV 13 filter as the standard for the city homes. A MERV 13 is specifically designed to capture the fine particles that characterize these peak pollution days. Because ozone levels also see significant increases, choosing a filter with an integrated activated carbon layer is highly effective for neutralizing gaseous pollutants that standard pleated filters miss. Change these filters every 60 to 90 days. In the Santa Clara Valley, dust and pollen accumulate quickly, and a loaded filter will drop your HVAC system's efficiency. If you have an older system that cannot handle the resistance of a MERV 13, use a MERV 11 and supplement it with a standalone HEPA air purifier in high-traffic rooms.