Typical air vs. spike days
- Annual average PM2.5 (9.71 µg/m³) reflects usual daily exposure.
- Worst-day peak PM2.5 (53.70 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 Nampa without contradicting EPA-aligned thresholds.
Local Allergen Load
Seasonal shifts bring a heavy load of pollen and mold spores to Canyon County. The proximity to the Boise River and surrounding agricultural lands means dust and biological allergens are constant variables. These particles accumulate on your evaporator coils and inside ductwork if your filtration isn't up to the task. During the transition into spring and the dry heat of late summer, the sheer volume of airborne debris can quickly saturate a standard filter, reducing its efficiency and potentially stressing your HVAC motor.
Technician's Filter Recommendations
Because PM2.5 peaks in Nampa exceed 25 µg/m³, a MERV 13 filter is the professional recommendation. Standard fiberglass or low-grade pleated filters will not capture the fine particulates seen during the city's worst air days.
- Primary Filter: MERV 13 pleated filter for the main HVAC return.
- Replacement Schedule: Every 60 to 90 days. If you notice a heavy dust load or have high indoor traffic, check it monthly.
- Supplemental Support: A dedicated HEPA unit in sleeping areas is the most effective setup for this specific data profile.