Typical air vs. spike days
- Annual average PM2.5 (8.74 µg/m³) reflects usual daily exposure.
- Worst-day peak PM2.5 (32.21 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 New Albany without contradicting EPA-aligned thresholds.
Regional Pollen and Mold Load
In the Ohio River Valley, humidity and heavy seasonal pollen are the primary drivers of indoor air quality issues. Mold spores thrive in the damp Indiana summers, while tree and grass pollen create a heavy biological load in the spring and fall. These particles are much larger than PM2.5 but they clog filters just as effectively. When the wind picks up near the river, it carries a mix of organic debris that settles into ductwork. Keeping a clean filter is less about smog and more about managing this constant influx of local allergens that can accumulate on your HVAC coils.
Technician's Filter Recommendations
Based on the peak PM2.5 exceeding 25 µg/m³, I recommend a MERV 13 pleated filter for most New Albany homes. A MERV 13 is dense enough to capture the fine particulates seen during those worst-day spikes without putting excessive strain on a modern blower motor. Because ozone peaks also hit 0.0781 ppm, consider a filter with an activated carbon layer if you notice chemical smells or stale air during the summer. In this region, humidity makes filters get heavy and loaded faster than in drier climates. Follow these maintenance rules:
- Check your filter every 30 days.
- Replace it at least every 60 to 90 days.
- If the filter looks grey or is beginning to bow, replace it immediately to protect the blower motor.
- Use a standard MERV 11 as a bare minimum if MERV 13 causes too much static pressure.