Typical air vs. spike days
- Annual average PM2.5 (8.81 µg/m³) reflects usual daily exposure.
- Worst-day peak PM2.5 (36.36 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 Peoria without contradicting EPA-aligned thresholds.
Local Allergen Load
The Illinois River valley tends to trap moisture and airborne irritants, creating a prime environment for mold spores and heavy pollen counts. Trees like oak, hickory, and maple contribute to a heavy spring load, while late summer brings ragweed and agricultural dust. This biological load puts a physical strain on your HVAC system. When pollen and mold counts rise, the 'dust' you see on your furniture is often the overflow that your filter couldn't catch because it was already at capacity. This makes regular filter maintenance critical during the transition between seasons.
Professional Filtration Advice
I recommend a MERV 13 filter for the city homes to handle those PM2.5 spikes that exceed 35 µg/m³. A MERV 13 is specifically designed to capture the fine particles that pass right through the cheap fiberglass or MERV 8 filters found at most hardware stores. If your HVAC system has a 1-inch filter slot, be aware that MERV 13 filters can be restrictive; you must change them every 60 days to prevent pressure backup and system wear. If you have a 4-inch or 5-inch media cabinet, you can usually extend this to 90 days. Given the 10.6% asthma prevalence in the area, a MERV 13 is the professional standard for maintaining a healthy baseline indoors. If you cannot upgrade the main filter due to the age of your furnace, a MERV 11 paired with a high-quality HEPA air scrubber in the main living area is the most effective alternative.