Typical air vs. spike days
- Annual average PM2.5 (8.47 µg/m³) reflects usual daily exposure.
- Worst-day peak PM2.5 (38.01 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 Brunswick without contradicting EPA-aligned thresholds.
Coastal Humidity and Pollen Factors
Being a coastal area, the air in Brunswick carries a mix of salt spray, high humidity, and heavy seasonal pollen. Live oaks and local marsh grasses contribute to a high volume of airborne allergens. The humidity in Glynn County is a major factor for HVAC maintenance, as it encourages mold growth on damp coils and within ductwork if filtration is poor. Near the coast, moisture levels stay high, meaning filters can become damp and lose their structural integrity. This makes the choice of a synthetic, moisture-resistant filter media more important than in drier climates to prevent microbial growth on the filter itself.
Technician's Filter Recommendations
Because the PM2.5 max exceeds 25 µg/m³—hitting 38.01 µg/m³—I recommend a MERV 13 pleated filter for all local homes. This is the minimum grade required to effectively capture the fine particles seen during those peak events. Given the coastal humidity, ensure you choose a filter with a sturdy, moisture-resistant frame to prevent sagging or air bypass. Filters in this area should be inspected monthly and replaced every 60 to 90 days. If you notice a musty smell when the air conditioning kicks on, the filter may be loaded with organic material and moisture. For those sensitive to the 0.0617 ppm ozone peaks, a filter with an activated carbon layer can provide additional protection, though the priority remains managing the high particulate spikes.