Typical air vs. spike days
- Annual average PM2.5 (8.38 µg/m³) reflects usual daily exposure.
- Worst-day peak PM2.5 (29.79 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 Augusta without contradicting EPA-aligned thresholds.
Savannah River Basin Environmental Factors
The Savannah River basin contributes to high localized humidity, which directly impacts how long particulates stay trapped in the lower atmosphere. Augusta's heavy pollen counts from local hardwoods and pines add a thick layer of biological dust to the air. This material does more than trigger allergies; it coats your HVAC blower motor and clogs the cooling coils. This reduces the system's efficiency and can lead to expensive repairs if the filtration isn't changed frequently enough to handle the organic load.
Technician's Filter Recommendations
Because the PM2.5 max exceeds 25 µg/m³, I recommend a MERV 13 pleated filter for Augusta homes. This rating is specifically designed to capture the fine particles measured in the 29.79 µg/m³ spikes. Because of the humidity and heavy pollen load near the river, these filters should be swapped every 60 days. If you use a lower MERV 8 filter, you are likely letting the finest, most damaging dust pass right through your system and back into your living space. For households with respiratory issues, supplementing the central system with a bedroom HEPA unit is a smart move.