Typical air vs. spike days
- Annual average PM2.5 (8.66 µg/m³) reflects usual daily exposure.
- Worst-day peak PM2.5 (37.26 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 Pflugerville without contradicting EPA-aligned thresholds.
Regional Pollen and Mold Loads
Seasonal loads in Travis County are driven heavily by cedar, oak, and ragweed cycles. The Colorado River and local greenbelts contribute to mold spores that thrive in the humidity. These biological particles are often larger than PM2.5 but can quickly clog a high-efficiency filter, reducing airflow and straining your blower motor. During cedar season, the sheer volume of pollen can overwhelm low-grade fiberglass filters, allowing fine dust to settle on your cooling coils and reduce system efficiency.
Technician Filter Recommendations
Because PM2.5 peaks exceed 25 µg/m³, I recommend a MERV 13 pleated filter for your central system. This rating is dense enough to capture the fine combustion particles and smoke that characterize those worst-day spikes. Since ozone also hits high peaks of 0.0813 ppm, look for a filter with an activated carbon layer to help neutralize odors and gaseous pollutants. In Central Texas, humidity and high pollen counts mean you should check these filters every 30 days and replace them at least every 60 to 90 days. A clogged MERV 13 filter will restrict airflow, which can lead to frozen evaporator coils during a Pflugerville summer. For residents with asthma, supplementing the HVAC filter with a standalone HEPA unit in high-traffic rooms is the best way to manage the 9.1% community sensitivity rate.