St. Lawrence, Pennsylvania Air Quality
St. Lawrence has a median AQI of 44, earning an air quality grade of A- — excellent air quality that ranks better than 31% of US cities. Air quality has been improving steadily over the past decade, a positive sign for residents. Ground-level ozone is the primary concern, typically peaking on warm sunny days due to vehicle and industrial emissions. In 2025, St. Lawrence recorded 139 good air quality days (66% of monitored days) and 2 unhealthy days.
Population: 1,851 • County: Berks
Current AQI
Quick Facts
| Current AQI | 16 — Good |
| Air Quality Grade | A- |
| Median AQI (2025) | 44 |
| vs. U.S. Cities | Better than 31% |
| Primary Pollutant | Ozone |
| Unhealthy Days/Year | 2 |
| 10-Year Trend | ↑ Improving |
| Data Source | EPA AQS (historical) · AirNow (live) |
Health Recommendation
Air quality is satisfactory, and air pollution poses little or no risk.
It's a great day to be active outside!
5-Day AQI Forecast
Last 90 Days
Current Pollutant Levels
Real-time data from EPA AirNow
Local Air Quality Context
Air quality data for St. Lawrence is sourced from the Reading Airport monitoring area, located approximately 7 miles from city center. This EPA-certified station continuously tracks ground-level ozone, the primary driver of air quality alerts in this area.
St. Lawrence has relatively consistent air quality throughout the year without a strong seasonal peak. Air quality is primarily influenced by local traffic, industrial activity, and regional weather patterns rather than a single seasonal driver.
AQI Trend (10 Years)
Air Quality Days by Year
St. Lawrence Median AQI by Year
Annual EPA air quality data for St. Lawrence — median AQI, day-category breakdown, and primary pollutant per year.
| Year | Median AQI | Good Days | Unhealthy Days | Max AQI | Primary Pollutant |
|---|---|---|---|---|---|
| 2025 | 44 | 139 | 2 | 122 | Ozone |
| 2024 | 43 | 254 | 2 | 105 | Ozone |
| 2023 | 48 | 205 | 12 | 287 | PM2.5 |
| 2022 | 44 | 240 | 2 | 101 | PM2.5 |
| 2021 | 48 | 198 | 5 | 133 | PM2.5 |
| 2020 | 44 | 227 | 1 | 102 | PM2.5 |
| 2019 | 44 | 230 | 6 | 170 | PM2.5 |
| 2018 | 44 | 226 | 5 | 117 | PM2.5 |
| 2017 | 49 | 184 | 5 | 122 | PM2.5 |
| 2016 | 54 | 136 | 7 | 129 | PM2.5 |
Source: EPA Air Quality System (AQS) annual summaries. "Unhealthy Days" includes Unhealthy for Sensitive Groups, Unhealthy, Very Unhealthy, and Hazardous categories.
2025 Air Quality Summary
Primary Pollutant Days (2025)
Days when each pollutant was the primary driver of AQI. Learn about pollutants →
Frequently Asked Questions About St. Lawrence Air Quality
What is the air quality in St. Lawrence today?
The current AQI in St. Lawrence is 16, rated "Good". Air quality is good — outdoor activity is safe for everyone today. Air quality is satisfactory, and air pollution poses little or no risk.
Is air quality in St. Lawrence getting better or worse?
Air quality in St. Lawrence has been improving. The median AQI has dropped 10 points (from 54 in 2016 to 44 in 2025), a positive trend for residents.
What is the most common air pollutant in St. Lawrence?
Ozone is the primary air pollutant in St. Lawrence, responsible for 116 days (55% of monitored days) in 2025. Ground-level ozone forms when sunlight reacts with emissions from vehicles and industry, typically peaking on hot summer afternoons.
How many unhealthy air days does St. Lawrence have per year?
In 2025, St. Lawrence recorded 66% good air quality days (139 days) out of 212 monitored days. There were 2 Unhealthy for Sensitive Groups days and 0 Unhealthy days (AQI above 100). The highest single-day AQI recorded was 122.
What air quality grade does St. Lawrence receive?
St. Lawrence receives an air quality grade of A-, placing it better than 31% of US cities. This is based on a median AQI of 44 in 2025, with 139 good air quality days. The EPA monitors air quality in this area continuously using certified monitoring stations.
Air Quality Grade
Better than 31% of US cities
Nearby Cities
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National Rankings
See how St. Lawrence compares to every other US city by air quality.
Best Air Quality Cities →All city rankingsRecommended Air Purifiers for St. Lawrence
Ozone is St. Lawrence's primary pollutant. Standard HEPA filters don't capture ozone molecules — you need activated carbon or PECO technology to chemically break them down. We highlight those units here.
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Other Great Options
Molekule Air Pro
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Honeywell HPA300
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