Typical air vs. spike days
- Annual average PM2.5 (14.18 µg/m³) reflects usual daily exposure.
- Worst-day peak PM2.5 (81.69 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 Lemoore without contradicting EPA-aligned thresholds.
Seasonal Load and Dust
Seasonal shifts bring a heavy dust and pollen load to this part of the Central Valley. In the area surrounding Lemoore, the proximity to the Kings River and expansive agricultural lands means high concentrations of organic matter and mold spores throughout the year. These particles do more than just irritate the lungs; they settle in your ductwork and coat your evaporator coils, which can lead to system failure if not managed. The dust load here is significantly higher than in coastal regions, requiring more frequent filter inspections.
Technician Filter Recommendations
Given the 81.69 µg/m³ PM2.5 peak, a MERV 13 pleated filter is the minimum requirement for local HVAC systems. Standard MERV 8 filters are designed to protect the equipment from large dust bunnies, but they will not capture the fine particulates seen during Lemoore's peak events. Because ozone peaks also reach 0.0835 ppm, I recommend filters with an activated carbon layer to help neutralize gases and odors. Change these filters every 60 days. If you notice a gray film on your supply vents, it is a sign that the dust load is bypassing your current filter or your ductwork has leaks that need sealing.