Puerto Rico · County air quality · 2025
Catano County, Puerto Rico
Median AQI 45 (Good). 60.6% of monitored days rated Good, direct from EPA Air Quality System stations.
- 45
- Median AQI
- 60.6%
- Good-air days
- 0
- Unhealthy days
- 16%
- Cleaner than US counties
Catano County's 2025 annual median AQI is 45 (Good), with 60.6% Good days
According to the U.S. EPA Air Quality System, Catano County, Puerto Rico posted a 2025 median AQI of 45 (Good) across 345 monitored days, with 60.6% rated Good and 0 unhealthy or worse. This is an annual comparison, not today's advisory.
Data source EPA Air Quality System (AQS)
- Cleaner than US
- Catano County's 60.6% Good-day share places it cleaner than 16% of US counties in 2025.
- Closest median-AQI peer
- Baltimore County (64.7% Good, median AQI 45) is the closest nationwide median-AQI peer to Catano County.
- 2020–2025 trend
- Catano County's floor-qualifying Good-day share is worsening from 2020 to 2025 (76.7% → 60.6%).
- Median AQI
- Median AQI: 45
According to the 2025 EPA AQS county release on PlainAirData, Catano County, Puerto Rico ranks #750 of 951 by median AQI (45) and #799 by good-day share (60.6%). Ponce County, Puerto Rico is #1 of 951 by median AQI (3, 91.4% Good days) at good-day-share #159 ≠ largest of 7 at 100.0% Good days #1 by good-day share (100.0%, median AQI 9) at median-AQI #7.
Annual release change
What changed in the 2025 EPA annual release
- Catano County's Good-day share rose from 49.6% to 60.6% between the 2024 and 2025 EPA annual releases, a change of +11.0 percentage points.
- Catano County's Unhealthy-category days fell from 11 to 0 between the 2024 and 2025 EPA annual releases, a change of -11 days.
- Catano County's peak single-day AQI fell from 162 to 99 between the 2024 and 2025 EPA annual releases, a change of -63 points.
- Catano County's median AQI fell from 51 to 45 between the 2024 and 2025 EPA annual releases, a change of -6 points.
Data updated August 2026
- Good · 209 d · 60.6%
- Moderate · 136 d · 39.4%
How did Catano County's air break down in 2025?
Across 345 monitored days, 209 fell in the Good band (AQI 0–50) and 0 reached Unhealthy or worse. The worst single day peaked at AQI 99 (Moderate).
EPA AQS →Share of monitored days at AQI 0-50 (Good band).
Share of monitored days above AQI 150 (Unhealthy or worse). Bar maxes at 10% (worst-county ceiling).
Where Catano County sits nationally
COUNT-derived placement among 951 US counties with at least 100 monitored days in 2025. Catano County's Good-day share is 60.6% - cleaner than 16% of that comparison set.
Catano County Good-day share vs. every US county
Share of monitored days in the Good band (AQI 0–50) - EPA AQS annual release
60.6% 16th percentile higher than 16% of 951 US counties
Each bar is a band; taller bars hold more US counties. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count, share, and where it sits relative to this entry.
Source U.S. Environmental Protection Agency, Air Quality System (AQS) · 2025
Pollutant Breakdown
Days where each pollutant was the primary driver of AQI readings in Catano County.
- PM2.5 · 328 days · 95.1%
- PM10 · 17 days · 4.9%
2024 daily-monitor rhythm in Catano County
Month-by-month median AQI from EPA day-level county monitors (339 reported days in 2024). May posted the highest typical readings (median AQI 124, peak 155); Nov was cleanest at median 26. Summer months (Jun–Aug) averaged median AQI 48 vs 54 in Dec–Feb. 11 days crossed Unhealthy (AQI >150) at least once that year.
Five-year seasonal record
EPA day-level county files · 2020–20241,428 daily readings show a recurring local pattern: May has the highest matched-month median AQI (59), while Jan is lowest (29). Each cell is that month’s median daily AQI, not a current-air forecast.
Lower AQI is better. The colors summarize EPA AQI bands; gaps mean the county had no day-level record for that month.
Health Impact Assessment
Catano County's air quality is rated Moderate based on 60.6% good air days. No unhealthy air days were recorded in 2025.
Air quality was acceptable on 60.6% of monitored days in 2025, with a median AQI of 45. Unusually sensitive people can check real-time conditions at AirNow.gov during high-pollution events.
The dominant pollutant is PM2.5, driving AQI on 328 of 345 monitored days.
5-Year Air Quality Trend
Air quality is worsening in Catano County. Highest Good-day share: 2020 (76.7%, 207 of 271 monitored days).
| Year | Good | Moderate | USG | Unhealthy | Median AQI | Max AQI |
|---|---|---|---|---|---|---|
| 2020 | 207 | 52 | 5 | 6 | 28 | 332 |
| 2021 | 151 | 136 | 12 | 1 | 50 | 151 |
| 2022 | 228 | 81 | 0 | 0 | 35 | 86 |
| 2023 | 96 | 101 | 10 | 2 | 52 | 155 |
| 2024 | 168 | 130 | 30 | 11 | 51 | 162 |
| 2025 | 209 | 136 | 0 | 0 | 45 | 99 |
How does Catano County compare?
How Catano County compares
Data Sources
Primary Source: U.S. Environmental Protection Agency (EPA), Air Quality System (AQS), Annual AQI by County dataset, 2020–2025 (aqs.epa.gov). For current conditions (not shown here — this page is historical annual data), see EPA AirNow (airnow.gov). See our methodology for how AQI, median, and coverage figures are computed.
Informational only, not professional advice. Data from EPA AQS. See our disclaimer. Spotted a figure that looks wrong? Report a correction.
Source: U.S. EPA Air Quality System (AQS) Annual AQI by county summary files for Catano County, Puerto Rico · 2020–2025
Download this county's annual AQI row as CSV , with the same EPA fields and denominator shown on this page.
Every figure on PlainAirData is rendered directly from EPA AQS air-quality monitoring data, no number is typed in by an editor. This page draws directly on EPA AQS air-quality monitoring data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.