EnviroNearby

Humacao, Puerto Rico air quality history

Daily Air Quality Index summaries from EPA monitors in Humacao, Puerto Rico, 1997–2014.

96%
Good days in 2014
21
Median daily AQI, 2014
0
Days above 100 in 2014
51
Days with an AQI in 2014 (of 365)

In 2014, EPA reported a daily Air Quality Index (AQI) for Humacao, Puerto Rico on 51 days. 49 of those days (96%) were in the Good range, and the median daily AQI was 21. That median is about the same as the typical monitored county in Puerto Rico (median 19 across 7 counties), and lower than the typical monitored U.S. county (42). The main pollutant was fine particles (PM2.5) on 51 days.

EPA did not report an AQI for every day of 2014 here (51 of 365 days). Figures describe monitored days only; seasonal monitoring (for example, ozone measured only in warmer months) can make a county look cleaner or dirtier than a full-year record would.

The most recent year with data for this county is 2014; EPA's files for 2015–2025 contain no row for it, which usually means its monitors stopped reporting.

Years with fewer than 120 monitored days (2007, 2008, 2011, 2012, 2013, 2014…) are shown in the table but left out of comparisons and trend statements.

How the days broke down each year

Each bar is one year. The colored segments show the share of monitored days that fell in each AQI category.

Share of monitored days in each AQI category, by year0%25%50%75%100%1997: Good 34 of 37 days1997: Moderate 3 of 37 days19971998: Good 45 of 47 days1998: Moderate 2 of 47 days1999: Good 43 of 47 days1999: Moderate 4 of 47 days19992000: Good 83 of 93 days2000: Moderate 10 of 93 days2001: Good 97 of 112 days2001: Moderate 15 of 112 days20012002: Good 85 of 94 days2002: Moderate 9 of 94 days2003: Good 100 of 111 days2003: Moderate 11 of 111 days20032004: Good 99 of 108 days2004: Moderate 9 of 108 days2005: Good 102 of 116 days2005: Moderate 14 of 116 days20052006: Good 95 of 108 days2006: Moderate 13 of 108 days2007: Good 91 of 102 days2007: Moderate 11 of 102 days20072008: Good 1 of 1 days2011: Good 17 of 18 days2011: Moderate 1 of 18 days20112012: Good 94 of 109 days2012: Moderate 15 of 109 days2013: Good 104 of 110 days2013: Moderate 6 of 110 days20132014: Good 49 of 51 days2014: Moderate 2 of 51 days2014
  • Good
  • Moderate
  • Unhealthy for Sensitive Groups
  • Unhealthy
  • Very Unhealthy
  • Hazardous

Typical and high-end AQI over time

The median is the middle day of the year. The 90th percentile is the level that only the highest 10% of days exceeded.

Median and 90th-percentile daily AQI, by year0501001997: 90th percentile AQI 391998: 90th percentile AQI 321999: 90th percentile AQI 402000: 90th percentile AQI 512001: 90th percentile AQI 522002: 90th percentile AQI 492003: 90th percentile AQI 482004: 90th percentile AQI 452005: 90th percentile AQI 542006: 90th percentile AQI 522007: 90th percentile AQI 512008: 90th percentile AQI 202011: 90th percentile AQI 362012: 90th percentile AQI 542013: 90th percentile AQI 412014: 90th percentile AQI 441997: Median AQI 191998: Median AQI 161999: Median AQI 162000: Median AQI 242001: Median AQI 282002: Median AQI 242003: Median AQI 232004: Median AQI 212005: Median AQI 222006: Median AQI 242007: Median AQI 262008: Median AQI 202011: Median AQI 132012: Median AQI 212013: Median AQI 212014: Median AQI 21199719992001200320052007201120132014
  • Median daily AQI
  • 90th-percentile daily AQI

Main pollutant by day, 2014

On each monitored day, the AQI reflects whichever measured pollutant had the highest index. This counts how many days each pollutant set the AQI. A pollutant that was not measured here cannot appear.

PollutantDays as main pollutantShare of monitored days
Fine particles (PM2.5)51100%

Year-by-year data

Annual AQI summary by year
YearDays with AQIGoodModerateUnhealthy for Sensitive GroupsUnhealthyVery UnhealthyHazardousMedian AQI90th pct.Max AQIMain pollutant
2014514920000214458PM2.5
201311010460000214158PM2.5
201210994150000215468PM2.5
2011181710000133661PM2.5
20081100000202020PM2.5
200710291110000265184PM2.5
200610895130000245272PM2.5
2005116102140000225473PM2.5
20041089990000214563PM2.5
2003111100110000234879PM2.5
2002948590000244966PM2.5
200111297150000285273PM2.5
20009383100000245175PM2.5
1999474340000164057PM10
1998474520000163285PM10
1997373430000193988PM10

What this data can and can’t tell you

It is a county-level summary. EPA reports one AQI per day for the county, based on the monitors operating there. Air at a particular street, school or home can differ, especially near roads, industry or wildfire smoke.

It is not a health assessment. The AQI is EPA’s scale for communicating daily air quality. A county’s history can’t tell you what the health risk is for any particular person. For daily conditions and health guidance, see AirNow.

Rules change over time. EPA has revised AQI breakpoints, most recently for fine particles in 2024, so some year-to-year change can reflect the scale rather than the air.

All monitored counties in Puerto Rico

Source: U.S. EPA AirData, “Annual AQI by County” files for 1997–2014 (EPA download page). EPA file dates: 2026-06-26. Imported into EnviroNearby November 5, 2026. How we use this data · Report a problem