What Is the Air Quality in Catano, Puerto Rico?
Catano, Puerto Rico has an Air Quality Grade of D (poor) with a 5-year median AQI of 42. The dominant pollutant is Fine Particulate Matter (PM2.5), and air quality has been worsening over the past decade.
Catano, Puerto Rico Air Quality Snapshot
| Air Quality Grade | D44/100 |
| 5-Year Median AQI | 42 (Good) |
| Most Recent Median AQI (2023) | 52 (Moderate) |
| Dominant Pollutant | Fine Particulate Matter (PM2.5) |
| 10-Year Trend | Worsening (+3.27 AQI/yr) |
| Unhealthy Days (last 5 yr) | 48 |
| National Rank (cleanest = #1) | #604 of 1,020 (59th most polluted percentile) |
| Puerto Rico Rank | #11 of 11 |
What Does the D Grade Mean?
Catano, Puerto Rico earns a D — air quality falls below the U.S. average, with a 5-year median AQI of 42. Residents with asthma, COPD, heart disease, or young children should watch daily AQI forecasts and limit outdoor exertion when alerts go out.
Catano, Puerto Rico's 5-year median AQI of 42 is right around the national average of 41 across the 1,020 monitored U.S. cities tracked here. Within Puerto Rico, Catano, Puerto Rico runs more polluted than the state average of 23 — local sources or geography are concentrating pollution above the state's typical reading.
For context within Puerto Rico: Caguas, Puerto Rico currently holds the state's cleanest grade (A, AQI 10), while Mayagnez, Puerto Rico sits at the bottom (C, AQI 31).
What's in Catano, Puerto Rico's Air?
The dominant pollutant in Catano, Puerto Rico is Fine Particulate Matter (PM2.5). Fine particulate matter — particles less than 2.5 micrometers across — comes mostly from combustion: vehicle exhaust, wildfire smoke, residential wood burning, and industrial emissions. Because these particles are small enough to enter the bloodstream, PM2.5 is the pollutant most strongly linked to cardiovascular disease, respiratory illness, and premature death.
Days by Dominant Pollutant (2023)
| Pollutant | Days as Dominant | Share of Year |
|---|---|---|
| Fine Particulate Matter (PM2.5) | 156 | 75% |
| Coarse Particulate Matter (PM10) | 53 | 25% |
Is the Air Getting Better or Worse?
Air quality in Catano, Puerto Rico has been getting worse over the past decade, with median AQI climbing by roughly 3.3 points per year. That bucks the national trend of broad improvement, and most often reflects either growing wildfire smoke exposure (particularly across the West) or rising local emissions from population and freight growth.
In 2014, Catano, Puerto Rico posted a median AQI of 17. By 2023 that figure was 52 — a rise of 35 AQI points dirtier across 10 years of EPA records.
Year-by-Year AQI in Catano, Puerto Rico
| Year | Median AQI | Good Days | Unhealthy Days | Dominant Pollutant |
|---|---|---|---|---|
| 2014 | 17 | 346 | 0 | PM10 |
| 2015 | 19 | 337 | 1 | PM10 |
| 2016 | 24 | 339 | 2 | PM2.5 |
| 2017 | 33 | 190 | 2 | PM2.5 |
| 2018 | 47 | 158 | 2 | PM2.5 |
| 2019 | 45 | 194 | 11 | PM2.5 |
| 2020 | 28 | 207 | 12 | Ozone |
| 2021 | 50 | 151 | 13 | PM2.5 |
| 2022 | 35 | 228 | 0 | PM2.5 |
| 2023 | 52 | 96 | 12 | PM2.5 |
Health Context for Catano, Puerto Rico
Across the past five years, this area has logged 48 days where AQI rose into the "Unhealthy for Sensitive Groups" range or worse — about 10 days per year. That is roughly typical for a U.S. metro, with most caution days clustered in summer (ozone) or wildfire season.
Treat daily AQI forecasts as essential input. On flagged days, sensitive groups (asthma, COPD, heart disease, pregnancy, young children, older adults) should limit outdoor exertion and keep windows closed. A HEPA air cleaner sized to a bedroom or family room can cut indoor PM2.5 by 80%+ during smoke or pollution events. Because PM2.5 penetrates deep into the lungs and bloodstream, an N95 or KN95 mask provides meaningful protection on smoky or high-particulate days — surgical masks do not.
How This Grade Is Calculated
The AirHistory Air Quality Grade combines four signals: the 5-year median AQI (40% of the score), the 10-year trend direction (30%), the count of unhealthy days per year (20%), and the dominant pollutant type (10%). All four come directly from the EPA Air Quality System (AQS), which aggregates readings from federally certified monitors. Read the full methodology.
Catano, Puerto Rico has an Air Quality Grade of D (poor) with a 5-year median AQI of 42. The dominant pollutant is Fine Particulate Matter (PM2.5), and air quality has been worsening over the past decade.
This answer pulls from the EPA Air Quality System (AQS), the authoritative federal source for U.S. air quality and pollution monitoring. The headline number above is the direct answer; what follows is the additional context most readers need to use the answer for a real decision rather than just a fact lookup.
A practical caveat: the headline answer above reflects the most recent the EPA Air Quality System (AQS) vintage; underlying data is often revised for months after first publication, and the right reference for any specific decision is whichever vintage is current at the time of the decision. The as-of date is stamped on every page.
Source: EPA Outdoor Air Quality Data, 2026.