What is the PM10 level in Connecticut, USA at the moment?

The PM10 concentration in Connecticut, USA is 14.006 μg/m3 at the moment.

What is the sulfur dioxide (SO2) level in Connecticut, USA at the moment?

Currently, Connecticut, USA has a sulfur dioxide (SO2) concentration of 0.324 ppb.

What is the ozone (O3) level in Connecticut, USA at the moment?

The current ozone (O3) level in Connecticut, USA at the moment is 14.083 ppm.

What is the nitrogen dioxide (NO2) level in Connecticut, USA at the moment?

Nitrogen dioxide (NO2) level in Connecticut, USA at the moment is 18.335 ppb.

Live air quality index in Connecticut, USA today

Q: What is the PM2.5 level in Connecticut, USA at the moment?

PM2.5 levels in Connecticut, USA are currently 4.429 μg/m3.

Stay updated with real-time air quality in Connecticut, USA featuring accurate data on AQI, PM_2.5, PM₁₀, O₃, NO₂, SO₂, and CO levels. Use our interactive map and detailed forecasts to monitor pollution trends, manage health risks, and plan your daily activities with confidence.

Live AQI (Air Quality Index)

Good

Connecticut, USA

Last updated: ... (Local time)

Major air pollutants in Connecticut, USA

Good

Fine

Moderate

Poor

Very poor

Hazardous

Particulate Matter_2.5 (PM_2.5)

4.77 μg/m³

12.1

35.5

55.5

250.5

500.5+

Particulate Matter₁₀ (PM₁₀)

15.30 μg/m³

155

255

425

605+

Ozone (O₃)

11.66 ppb

201

201+

Sulfur Dioxide (SO₂)

0.37 ppb

186

605

1005+

Nitrogen Dioxide (NO₂)

17.56 ppb

101

361

1250

2050+

Carbon Monoxide (CO)

0.43 ppm

4.5

9.5

12.5

230.5

50.5+

Pollen Level

Low

Connecticut, USA

Get Live Pollen Counts

Connecticut, USA

Scroll To Air Quality Map

Track live Connecticut, USA air quality forecast and history

Time	AQI	PM_2.5	PM₁₀	O₃	SO₂	NO₂	CO
2026-10-07T14:00:00.000Z	40 \| good	6.025 \| good	43.102 \| good	11.943 \| good	0.446 \| good	16.969 \| good	0.414 \| good
2026-10-07T15:00:00.000Z	33 \| good	5.642 \| good	33.481 \| good	14.143 \| good	0.558 \| good	16.875 \| good	0.393 \| good
2026-10-07T16:00:00.000Z	27 \| good	4.679 \| good	27.892 \| good	16.241 \| good	0.496 \| good	11.053 \| good	0.288 \| good
2026-10-07T17:00:00.000Z	22 \| good	3.858 \| good	24.302 \| good	18.46 \| good	0.634 \| good	11.083 \| good	0.225 \| good
2026-10-07T18:00:00.000Z	22 \| good	3.165 \| good	19.169 \| good	24.197 \| good	0.515 \| good	8.708 \| good	0.202 \| good
2026-10-07T19:00:00.000Z	29 \| good	3.095 \| good	17.547 \| good	31.196 \| good	0.478 \| good	9.427 \| good	0.258 \| good
2026-10-07T20:00:00.000Z	29 \| good	3.551 \| good	22.059 \| good	31.112 \| good	0.6 \| good	8.102 \| good	0.258 \| good
2026-10-07T21:00:00.000Z	33 \| good	3.243 \| good	19.617 \| good	36.187 \| good	0.512 \| good	7.346 \| good	0.222 \| good
2026-10-07T22:00:00.000Z	33 \| good	3.09 \| good	15.304 \| good	35.961 \| good	0.379 \| good	8.542 \| good	0.251 \| good
2026-10-07T23:00:00.000Z	35 \| good	3.275 \| good	14.372 \| good	37.913 \| good	0.495 \| good	10.548 \| good	0.23 \| good
2026-10-08T00:00:00.000Z	31 \| good	3.475 \| good	12.614 \| good	33.141 \| good	0.507 \| good	10.994 \| good	0.23 \| good
2026-10-08T01:00:00.000Z	30 \| good	3.686 \| good	11.745 \| good	31.624 \| good	0.405 \| good	10.364 \| good	0.23 \| good
2026-10-08T02:00:00.000Z	31 \| good	3.983 \| good	10.924 \| good	32.868 \| good	0.287 \| good	8.533 \| good	0.222 \| good
2026-10-08T03:00:00.000Z	38 \| good	6.854 \| good	30.553 \| good	30.896 \| good	0.895 \| good	7.867 \| good	0.167 \| good
2026-10-08T04:00:00.000Z	29 \| good	4.197 \| good	10.962 \| good	30.607 \| good	0.299 \| good	8.463 \| good	0.251 \| good
2026-10-08T05:00:00.000Z	27 \| good	4.011 \| good	10.079 \| good	29.144 \| good	0.396 \| good	5.175 \| good	0.244 \| good
2026-10-08T06:00:00.000Z	25 \| good	3.795 \| good	9.079 \| good	26.541 \| good	0.255 \| good	6.106 \| good	0.244 \| good
2026-10-08T07:00:00.000Z	30 \| good	3.803 \| good	9.052 \| good	32.157 \| good	0.159 \| good	5.664 \| good	0.201 \| good
2026-10-08T08:00:00.000Z	31 \| good	3.966 \| good	9.049 \| good	33.316 \| good	0.259 \| good	6.147 \| good	0.251 \| good
2026-10-08T09:00:00.000Z	30 \| good	4.041 \| good	9.819 \| good	31.94 \| good	0.273 \| good	6.419 \| good	0.244 \| good
2026-10-08T10:00:00.000Z	26 \| good	4.159 \| good	9.844 \| good	27.505 \| good	0.483 \| good	8.907 \| good	0.243 \| good
2026-10-08T11:00:00.000Z	25 \| good	4.458 \| good	12.502 \| good	26.862 \| good	1.13 \| good	10.853 \| good	0.273 \| good
2026-10-08T12:00:00.000Z	33 \| good	6.082 \| good	33.333 \| good	29.588 \| good	1.097 \| good	11.985 \| good	0.324 \| good
2026-10-08T13:00:00.000Z	33 \| good	6.125 \| good	33.761 \| good	27.106 \| good	1.435 \| good	11.128 \| good	0.284 \| good
2026-10-08T14:00:00.000Z	33 \| good	5.93 \| good	22.989 \| good	26.652 \| good	0.406 \| good	12.079 \| good	0.31 \| good
2026-10-08T15:00:00.000Z	33 \| good	5.567 \| good	22.977 \| good	27.409 \| good	0.384 \| good	8.883 \| good	0.31 \| good
2026-10-08T16:00:00.000Z	37 \| good	6.102 \| good	40.469 \| good	29.626 \| good	0.278 \| good	7.99 \| good	0.295 \| good
2026-10-08T17:00:00.000Z	49 \| good	6.312 \| good	53.436 \| good	31.315 \| good	0.177 \| good	2.522 \| good	0.251 \| good
2026-10-08T18:00:00.000Z	47 \| good	5.897 \| good	50.97 \| good	36.499 \| good	0.18 \| good	2.739 \| good	0.261 \| good
2026-10-08T19:00:00.000Z	56 \| moderate	6.082 \| good	64.971 \| fine	37.744 \| good	0.181 \| good	3.162 \| good	0.272 \| good
2026-10-08T20:00:00.000Z	44 \| good	4.75 \| good	47.789 \| good	39.522 \| good	0.256 \| good	3.482 \| good	0.263 \| good
2026-10-08T21:00:00.000Z	36 \| good	3.744 \| good	32.808 \| good	39.156 \| good	0.164 \| good	2.919 \| good	0.254 \| good
2026-10-08T22:00:00.000Z	37 \| good	3.304 \| good	23.182 \| good	39.603 \| good	0.267 \| good	4.693 \| good	0.254 \| good
2026-10-08T23:00:00.000Z	33 \| good	3.066 \| good	15.332 \| good	36.145 \| good	0.281 \| good	8.96 \| good	0.316 \| good
2026-10-09T00:00:00.000Z	31 \| good	3.204 \| good	12.697 \| good	33.53 \| good	0.222 \| good	14.144 \| good	0.326 \| good
2026-10-09T01:00:00.000Z	24 \| good	4.115 \| good	14.405 \| good	26.327 \| good	0.154 \| good	18.602 \| good	0.329 \| good
2026-10-09T02:00:00.000Z	25 \| good	4.497 \| good	14.483 \| good	26.609 \| good	0.179 \| good	21.662 \| good	0.407 \| good
2026-10-09T03:00:00.000Z	19 \| good	2.545 \| good	10.532 \| good	19.52 \| good	0.425 \| good	5.846 \| good	0.16 \| good
2026-10-09T04:00:00.000Z	27 \| good	4.947 \| good	14.357 \| good	24.796 \| good	0.313 \| good	20.553 \| good	0.296 \| good
2026-10-09T05:00:00.000Z	22 \| good	4.347 \| good	10.02 \| good	21.522 \| good	0.341 \| good	22.618 \| good	0.429 \| good
2026-10-09T06:00:00.000Z	22 \| good	4.32 \| good	9.963 \| good	21.771 \| good	0.499 \| good	19.67 \| good	0.273 \| good
2026-10-09T07:00:00.000Z	22 \| good	4.168 \| good	9.905 \| good	17.646 \| good	0.327 \| good	18.307 \| good	0.287 \| good
2026-10-09T08:00:00.000Z	22 \| good	4.186 \| good	9.101 \| good	12.761 \| good	0.317 \| good	18.178 \| good	0.327 \| good
2026-10-09T09:00:00.000Z	22 \| good	4.199 \| good	9.145 \| good	16.066 \| good	0.392 \| good	20.361 \| good	0.269 \| good
2026-10-09T10:00:00.000Z	22 \| good	4.28 \| good	13.377 \| good	13.537 \| good	0.377 \| good	19.6 \| good	0.348 \| good
2026-10-09T11:00:00.000Z	22 \| good	4.446 \| good	19.46 \| good	14.299 \| good	0.506 \| good	20.028 \| good	0.414 \| good
2026-10-09T12:00:00.000Z	33 \| good	5.049 \| good	35.893 \| good	11.178 \| good	0.342 \| good	18.839 \| good	0.408 \| good
2026-10-09T13:00:00.000Z	33 \| good	5.041 \| good	36.262 \| good	21.051 \| good	0.379 \| good	17.695 \| good	0.36 \| good
2026-10-09T13:00:00.000Z	27 \| good	4.77 \| good	15.296 \| good	11.657 \| good	0.371 \| good	17.561 \| good	0.434 \| good
2026-10-09T12:00:00.000Z	27 \| good	5.175 \| good	22.66 \| good	16.598 \| good	0.443 \| good	5.143 \| good	0.159 \| good
2026-10-09T13:00:00.000Z	19 \| good	3.483 \| good	15.127 \| good	20.3 \| good	0.426 \| good	4.002 \| good	0.163 \| good
2026-10-09T14:00:00.000Z	24 \| good	2.77 \| good	11.724 \| good	26.172 \| good	0.458 \| good	2.465 \| good	0.146 \| good
2026-10-09T15:00:00.000Z	27 \| good	2.36 \| good	9.84 \| good	29.042 \| good	0.488 \| good	1.436 \| good	0.136 \| good
2026-10-09T16:00:00.000Z	28 \| good	3.468 \| good	15.24 \| good	29.971 \| good	0.508 \| good	0.866 \| good	0.132 \| good
2026-10-09T17:00:00.000Z	30 \| good	4.384 \| good	18.829 \| good	32.099 \| good	0.519 \| good	0.657 \| good	0.133 \| good
2026-10-09T18:00:00.000Z	29 \| good	3.314 \| good	14.565 \| good	31.045 \| good	0.536 \| good	0.595 \| good	0.134 \| good
2026-10-09T19:00:00.000Z	27 \| good	2.248 \| good	9.264 \| good	29.389 \| good	0.55 \| good	0.567 \| good	0.136 \| good
2026-10-09T20:00:00.000Z	27 \| good	0.948 \| good	3.656 \| good	28.733 \| good	0.557 \| good	0.621 \| good	0.138 \| good
2026-10-09T21:00:00.000Z	26 \| good	0.364 \| good	1.15 \| good	28.086 \| good	0.556 \| good	0.955 \| good	0.143 \| good
2026-10-09T22:00:00.000Z	23 \| good	0.399 \| good	1.636 \| good	24.825 \| good	0.549 \| good	2.12 \| good	0.156 \| good
2026-10-09T23:00:00.000Z	20 \| good	0.957 \| good	3.639 \| good	22.461 \| good	0.556 \| good	4.556 \| good	0.18 \| good
2026-10-10T00:00:00.000Z	19 \| good	1.984 \| good	8.272 \| good	21.289 \| good	0.581 \| good	5.767 \| good	0.188 \| good
2026-10-10T01:00:00.000Z	17 \| good	1.769 \| good	7.253 \| good	18.459 \| good	0.598 \| good	5.673 \| good	0.182 \| good
2026-10-10T02:00:00.000Z	17 \| good	2.321 \| good	9.524 \| good	18.281 \| good	0.614 \| good	6.011 \| good	0.182 \| good
2026-10-10T03:00:00.000Z	16 \| good	2.687 \| good	11.189 \| good	17.474 \| good	0.618 \| good	6.228 \| good	0.183 \| good
2026-10-10T04:00:00.000Z	16 \| good	2.803 \| good	11.79 \| good	16.108 \| good	0.603 \| good	5.527 \| good	0.18 \| good
2026-10-10T05:00:00.000Z	16 \| good	3.406 \| good	14.855 \| good	15.423 \| good	0.59 \| good	4.624 \| good	0.175 \| good
2026-10-10T06:00:00.000Z	22 \| good	3.575 \| good	15.798 \| good	15.593 \| good	0.593 \| good	4.342 \| good	0.173 \| good
2026-10-10T07:00:00.000Z	22 \| good	3.701 \| good	16.334 \| good	16.414 \| good	0.602 \| good	4.449 \| good	0.173 \| good
2026-10-10T08:00:00.000Z	22 \| good	3.881 \| good	17.223 \| good	16.581 \| good	0.609 \| good	4.751 \| good	0.175 \| good
2026-10-10T09:00:00.000Z	22 \| good	4.102 \| good	18.029 \| good	14.39 \| good	0.612 \| good	5.152 \| good	0.179 \| good
2026-10-10T10:00:00.000Z	22 \| good	4.17 \| good	18.312 \| good	14.259 \| good	0.613 \| good	5.89 \| good	0.184 \| good
2026-10-10T11:00:00.000Z	27 \| good	5.256 \| good	23.078 \| good	13.943 \| good	0.62 \| good	7.632 \| good	0.198 \| good
2026-10-10T12:00:00.000Z	22 \| good	4.093 \| good	17.742 \| good	13.57 \| good	0.632 \| good	8.79 \| good	0.227 \| good
2026-10-10T13:00:00.000Z	22 \| good	4.192 \| good	18.374 \| good	16.658 \| good	0.545 \| good	5.525 \| good	0.217 \| good
2026-10-10T14:00:00.000Z	19 \| good	3.028 \| good	12.882 \| good	20.712 \| good	0.509 \| good	2.223 \| good	0.169 \| good
2026-10-10T15:00:00.000Z	21 \| good	1.157 \| good	4.725 \| good	23.306 \| good	0.446 \| good	1.294 \| good	0.156 \| good
2026-10-10T16:00:00.000Z	22 \| good	0.616 \| good	2.176 \| good	24.481 \| good	0.413 \| good	0.925 \| good	0.151 \| good
2026-10-10T17:00:00.000Z	23 \| good	0.521 \| good	2.027 \| good	25.217 \| good	0.396 \| good	0.76 \| good	0.148 \| good
2026-10-10T18:00:00.000Z	23 \| good	1.193 \| good	4.746 \| good	24.967 \| good	0.391 \| good	0.711 \| good	0.146 \| good
2026-10-10T19:00:00.000Z	22 \| good	0.912 \| good	3.421 \| good	24.354 \| good	0.392 \| good	0.748 \| good	0.146 \| good
2026-10-10T20:00:00.000Z	21 \| good	1.449 \| good	5.75 \| good	22.63 \| good	0.398 \| good	0.881 \| good	0.146 \| good
2026-10-10T21:00:00.000Z	19 \| good	1.802 \| good	7.245 \| good	21.386 \| good	0.393 \| good	1.836 \| good	0.158 \| good
2026-10-10T22:00:00.000Z	19 \| good	2.02 \| good	8.478 \| good	21.161 \| good	0.429 \| good	6.916 \| good	0.211 \| good
2026-10-10T23:00:00.000Z	19 \| good	2.95 \| good	12.455 \| good	20.484 \| good	0.519 \| good	13.928 \| good	0.275 \| good
2026-10-11T00:00:00.000Z	20 \| good	3.35 \| good	14.601 \| good	21.944 \| good	0.622 \| good	18.967 \| good	0.324 \| good
2026-10-11T01:00:00.000Z	22 \| good	3.996 \| good	17.248 \| good	19.582 \| good	0.719 \| good	21.291 \| good	0.349 \| good
2026-10-11T02:00:00.000Z	33 \| good	5.518 \| good	24.264 \| good	19.188 \| good	0.792 \| good	22.567 \| good	0.352 \| good
2026-10-11T03:00:00.000Z	33 \| good	6.136 \| good	26.789 \| good	18.113 \| good	0.855 \| good	22.439 \| good	0.338 \| good
2026-10-11T04:00:00.000Z	33 \| good	6.353 \| good	28.188 \| good	16.602 \| good	0.929 \| good	21.998 \| good	0.319 \| good
2026-10-11T05:00:00.000Z	38 \| good	6.779 \| good	30.008 \| good	14.937 \| good	1.003 \| good	21.577 \| good	0.306 \| good
2026-10-11T06:00:00.000Z	38 \| good	6.692 \| good	29.725 \| good	14.562 \| good	1.085 \| good	21.096 \| good	0.296 \| good
2026-10-11T07:00:00.000Z	44 \| good	7.595 \| good	33.306 \| good	13.851 \| good	1.152 \| good	20.535 \| good	0.286 \| good
2026-10-11T08:00:00.000Z	44 \| good	8.135 \| good	35.815 \| good	12.607 \| good	1.193 \| good	19.772 \| good	0.274 \| good
2026-10-11T09:00:00.000Z	49 \| good	9.212 \| good	40.889 \| good	13.631 \| good	1.213 \| good	18.945 \| good	0.26 \| good
2026-10-11T10:00:00.000Z	49 \| good	8.902 \| good	39.099 \| good	13.729 \| good	1.209 \| good	18.292 \| good	0.252 \| good
2026-10-11T11:00:00.000Z	54 \| moderate	11.11 \| good	48.91 \| good	13.72 \| good	1.191 \| good	17.936 \| good	0.252 \| good

Connecticut

Get reliable air quality data to drive your business

Connecticut, USA air quality map: Stay updated on AQI near you

Air quality in cities of Connecticut, USA

City	AQI	PM_2.5	PM₁₀	O₃	SO₂	NO₂	CO
Bethel, Connecticut	33 Good	5.95μg/m³ Good	13.70μg/m³ Good	8.17ppb Good	0.69ppb Good	20.40ppb Good	0.37ppm Good
Avon, Connecticut	22 Good	4.38μg/m³ Good	15.21μg/m³ Good	14.00ppb Good	0.30ppb Good	18.49ppb Good	0.45ppm Good
Berlin, Connecticut	27 Good	4.78μg/m³ Good	16.08μg/m³ Good	13.37ppb Good	0.33ppb Good	20.60ppb Good	0.45ppm Good
Bloomfield, Connecticut	33 Good	5.81μg/m³ Good	17.48μg/m³ Good	5.26ppb Good	0.29ppb Good	20.79ppb Good	0.48ppm Good
Ansonia, Connecticut	27 Good	5.06μg/m³ Good	13.29μg/m³ Good	7.48ppb Good	0.52ppb Good	22.89ppb Good	0.47ppm Good
Cheshire, Connecticut	33 Good	5.51μg/m³ Good	16.71μg/m³ Good	8.76ppb Good	0.49ppb Good	21.49ppb Good	0.44ppm Good
Branford, Connecticut	33 Good	5.66μg/m³ Good	14.87μg/m³ Good	4.37ppb Good	0.52ppb Good	24.41ppb Good	0.57ppm Good
Brookfield, Connecticut	33 Good	5.80μg/m³ Good	14.40μg/m³ Good	8.83ppb Good	0.69ppb Good	20.41ppb Good	0.37ppm Good
Bridgeport, Connecticut	22 Good	4.01μg/m³ Good	10.10μg/m³ Good	18.67ppb Good	0.66ppb Good	22.34ppb Good	0.43ppm Good
Bristol, Connecticut	27 Good	5.18μg/m³ Good	12.77μg/m³ Good	20.41ppb Good	0.39ppb Good	20.43ppb Good	0.39ppm Good
Canton, Connecticut	26 Good	3.06μg/m³ Good	28.06μg/m³ Good	21.79ppb Good	0.35ppb Good	16.09ppb Good	0.38ppm Good
Coventry, Connecticut	22 Good	3.82μg/m³ Good	9.71μg/m³ Good	18.38ppb Good	0.28ppb Good	16.39ppb Good	0.44ppm Good
Danbury, Connecticut	33 Good	6.09μg/m³ Good	13.04μg/m³ Good	7.45ppb Good	0.69ppb Good	20.38ppb Good	0.37ppm Good
East Lyme, Connecticut	24 Good	4.01μg/m³ Good	11.64μg/m³ Good	26.35ppb Good	0.31ppb Good	14.58ppb Good	0.45ppm Good
Clinton, Connecticut	27 Good	3.61μg/m³ Good	29.21μg/m³ Good	26.01ppb Good	0.35ppb Good	16.23ppb Good	0.46ppm Good
Darien, Connecticut	22 Good	3.17μg/m³ Good	23.52μg/m³ Good	20.88ppb Good	0.75ppb Good	7.47ppb Good	0.37ppm Good
Derby, Connecticut	27 Good	5.06μg/m³ Good	13.29μg/m³ Good	7.48ppb Good	0.52ppb Good	22.89ppb Good	0.47ppm Good
Colchester, Connecticut	22 Good	3.87μg/m³ Good	14.28μg/m³ Good	24.17ppb Good	0.30ppb Good	16.45ppb Good	0.44ppm Good
Cromwell, Connecticut	27 Good	4.63μg/m³ Good	14.71μg/m³ Good	13.64ppb Good	0.33ppb Good	20.63ppb Good	0.46ppm Good
Shelton, Connecticut	27 Good	5.06μg/m³ Good	13.29μg/m³ Good	7.48ppb Good	0.52ppb Good	22.89ppb Good	0.47ppm Good
East Hartford, Connecticut	27 Good	5.08μg/m³ Good	14.09μg/m³ Good	5.08ppb Good	0.29ppb Good	16.81ppb Good	0.48ppm Good
East Windsor, Connecticut	27 Good	4.72μg/m³ Good	17.26μg/m³ Good	5.68ppb Good	0.26ppb Good	18.43ppb Good	0.44ppm Good
East Haven, Connecticut	33 Good	5.94μg/m³ Good	14.99μg/m³ Good	2.29ppb Good	0.51ppb Good	25.66ppb Good	0.59ppm Good
East Hampton, Connecticut	22 Good	3.78μg/m³ Good	11.58μg/m³ Good	13.27ppb Good	0.32ppb Good	17.04ppb Good	0.45ppm Good
Fairfield, Connecticut	22 Good	4.19μg/m³ Good	15.05μg/m³ Good	18.08ppb Good	0.67ppb Good	20.50ppb Good	0.42ppm Good
Ellington, Connecticut	27 Good	4.57μg/m³ Good	26.46μg/m³ Good	14.51ppb Good	0.26ppb Good	18.98ppb Good	0.43ppm Good
Farmington, Connecticut	22 Good	3.52μg/m³ Good	11.11μg/m³ Good	16.55ppb Good	0.32ppb Good	20.21ppb Good	0.43ppm Good
Enfield, Connecticut	27 Good	4.51μg/m³ Good	18.76μg/m³ Good	11.90ppb Good	0.28ppb Good	18.20ppb Good	0.39ppm Good
Guilford, Connecticut	22 Good	4.46μg/m³ Good	19.35μg/m³ Good	21.53ppb Good	0.44ppb Good	22.12ppb Good	0.47ppm Good
Greenwich, Connecticut	22 Good	4.40μg/m³ Good	20.17μg/m³ Good	23.20ppb Good	0.79ppb Good	8.44ppb Good	0.36ppm Good
Hamden, Connecticut	33 Good	5.71μg/m³ Good	15.81μg/m³ Good	4.26ppb Good	0.49ppb Good	24.72ppb Good	0.56ppm Good
Glastonbury, Connecticut	27 Good	5.26μg/m³ Good	15.68μg/m³ Good	5.37ppb Good	0.29ppb Good	18.30ppb Good	0.47ppm Good
Groton, Connecticut	25 Good	3.99μg/m³ Good	8.07μg/m³ Good	26.51ppb Good	0.30ppb Good	9.46ppb Good	0.43ppm Good
New London, Connecticut	25 Good	3.99μg/m³ Good	8.07μg/m³ Good	26.51ppb Good	0.30ppb Good	9.46ppb Good	0.43ppm Good
Hartford, Connecticut	38 Good	6.51μg/m³ Good	19.66μg/m³ Good	5.12ppb Good	0.30ppb Good	23.86ppb Good	0.50ppm Good
Griswold, Connecticut	22 Good	3.56μg/m³ Good	17.30μg/m³ Good	18.14ppb Good	0.28ppb Good	15.78ppb Good	0.42ppm Good
Granby, Connecticut	19 Good	2.83μg/m³ Good	21.32μg/m³ Good	16.98ppb Good	0.31ppb Good	15.37ppb Good	0.38ppm Good
Killingly, Connecticut	24 Good	3.37μg/m³ Good	16.52μg/m³ Good	26.12ppb Good	0.34ppb Good	15.85ppb Good	0.37ppm Good
Ledyard, Connecticut	23 Good	3.77μg/m³ Good	10.30μg/m³ Good	24.52ppb Good	0.32ppb Good	10.26ppb Good	0.41ppm Good
Manchester, Connecticut	27 Good	5.08μg/m³ Good	14.54μg/m³ Good	5.52ppb Good	0.28ppb Good	17.45ppb Good	0.45ppm Good
Mansfield, Connecticut	22 Good	3.85μg/m³ Good	14.55μg/m³ Good	20.42ppb Good	0.27ppb Good	15.81ppb Good	0.43ppm Good
Milford, Connecticut	27 Good	4.91μg/m³ Good	12.64μg/m³ Good	12.22ppb Good	0.60ppb Good	20.23ppb Good	0.47ppm Good
Middletown, Connecticut	22 Good	4.00μg/m³ Good	13.49μg/m³ Good	12.52ppb Good	0.34ppb Good	20.79ppb Good	0.46ppm Good
Madison, Connecticut	22 Good	3.93μg/m³ Good	14.78μg/m³ Good	23.95ppb Good	0.36ppb Good	19.97ppb Good	0.47ppm Good
Meriden, Connecticut	27 Good	5.18μg/m³ Good	15.56μg/m³ Good	15.99ppb Good	0.41ppb Good	21.47ppb Good	0.44ppm Good
Monroe, Connecticut	27 Good	4.63μg/m³ Good	20.86μg/m³ Good	12.60ppb Good	0.64ppb Good	20.36ppb Good	0.41ppm Good
New Milford, Connecticut	28 Good	3.92μg/m³ Good	29.54μg/m³ Good	14.14ppb Good	0.67ppb Good	16.26ppb Good	0.32ppm Good
North Haven, Connecticut	33 Good	5.75μg/m³ Good	15.45μg/m³ Good	3.77ppb Good	0.50ppb Good	25.15ppb Good	0.57ppm Good
Old Saybrook, Connecticut	25 Good	3.68μg/m³ Good	27.12μg/m³ Good	24.74ppb Good	0.34ppb Good	15.55ppb Good	0.45ppm Good
New Fairfield, Connecticut	33 Good	5.57μg/m³ Good	14.98μg/m³ Good	9.47ppb Good	0.69ppb Good	19.84ppb Good	0.35ppm Good

City	AQI	PM_2.5	PM₁₀	O₃	SO₂	NO₂	CO
No results found

0.14ppm

How accurate is Connecticut, USA air quality data?

Air quality and pollutant data for Connecticut, USA are sourced from ground-based monitors and satellites, adhering to US EPA standards. Machine learning and advanced algorithms enhance the data by incorporating local variables like traffic and population density, ensuring high accuracy and dependability.

Source: Ambee Data Sources

Air quality levels in US

Check live rankings of places in the USA affected by air pollution.

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Check live rankings of places in the USA with the cleanest air.

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Frequently asked questions

How often is air quality information updated for Connecticut, USA?

The air quality information for Connecticut, USA is updated every hour for accuracy.

What time in the last 24 hours was the air quality in Connecticut, USA at its worst?

In the past 24 hours, the air quality in Connecticut, USA was at its worst at 07:00:00 on 2026-10-08.

When did Connecticut, USA experience the best air quality in the last 24 hours?

In the last 24 hours, the best air quality in Connecticut, USA was observed at 03:00:00 on 2026-10-09.

What is the AQI in Connecticut, USA right now?

As of now, the AQI in Connecticut, USA is 22, indicating Good conditions.

What is the most common type of pollution in Connecticut, USA?

Connecticut, USA air has the highest levels of PM2.5.

What should I do in case of poor air quality in Connecticut, USA?

Poor air quality in Connecticut, USA means it's advisable to stay indoors and wear a mask for your protection.

What is the PM_2.5 level in Connecticut, USA at the moment?

PM_2.5 levels in Connecticut, USA are currently 4.429 μg/m³.

What is the PM₁₀ level in Connecticut, USA at the moment?

The PM₁₀ concentration in Connecticut, USA is 14.006 μg/m³ at the moment.

What is the carbon monoxide (CO) level in Connecticut, USA at the moment?

The current carbon monoxide (CO) concentration in Connecticut, USA is 0.365 ppm.

What is the sulfur dioxide (SO₂) level in Connecticut, USA at the moment?

Currently, Connecticut, USA has a sulfur dioxide (SO₂) concentration of 0.324 ppb.

What is the ozone (O₃) level in Connecticut, USA at the moment?

The current ozone (O₃) level in Connecticut, USA at the moment is 14.083 ppm.

What is the nitrogen dioxide (NO₂) level in Connecticut, USA at the moment?

Nitrogen dioxide (NO₂) level in Connecticut, USA at the moment is 18.335 ppb.

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Time	AQI	PM_2.5	PM₁₀	O₃	SO₂	NO₂	CO
2026-10-07T14:00:00.000Z	40 \| good	6.025 \| good	43.102 \| good	11.943 \| good	0.446 \| good	16.969 \| good	0.414 \| good
2026-10-07T15:00:00.000Z	33 \| good	5.642 \| good	33.481 \| good	14.143 \| good	0.558 \| good	16.875 \| good	0.393 \| good
2026-10-07T16:00:00.000Z	27 \| good	4.679 \| good	27.892 \| good	16.241 \| good	0.496 \| good	11.053 \| good	0.288 \| good
2026-10-07T17:00:00.000Z	22 \| good	3.858 \| good	24.302 \| good	18.46 \| good	0.634 \| good	11.083 \| good	0.225 \| good
2026-10-07T18:00:00.000Z	22 \| good	3.165 \| good	19.169 \| good	24.197 \| good	0.515 \| good	8.708 \| good	0.202 \| good
2026-10-07T19:00:00.000Z	29 \| good	3.095 \| good	17.547 \| good	31.196 \| good	0.478 \| good	9.427 \| good	0.258 \| good
2026-10-07T20:00:00.000Z	29 \| good	3.551 \| good	22.059 \| good	31.112 \| good	0.6 \| good	8.102 \| good	0.258 \| good
2026-10-07T21:00:00.000Z	33 \| good	3.243 \| good	19.617 \| good	36.187 \| good	0.512 \| good	7.346 \| good	0.222 \| good
2026-10-07T22:00:00.000Z	33 \| good	3.09 \| good	15.304 \| good	35.961 \| good	0.379 \| good	8.542 \| good	0.251 \| good
2026-10-07T23:00:00.000Z	35 \| good	3.275 \| good	14.372 \| good	37.913 \| good	0.495 \| good	10.548 \| good	0.23 \| good
2026-10-08T00:00:00.000Z	31 \| good	3.475 \| good	12.614 \| good	33.141 \| good	0.507 \| good	10.994 \| good	0.23 \| good
2026-10-08T01:00:00.000Z	30 \| good	3.686 \| good	11.745 \| good	31.624 \| good	0.405 \| good	10.364 \| good	0.23 \| good
2026-10-08T02:00:00.000Z	31 \| good	3.983 \| good	10.924 \| good	32.868 \| good	0.287 \| good	8.533 \| good	0.222 \| good
2026-10-08T03:00:00.000Z	38 \| good	6.854 \| good	30.553 \| good	30.896 \| good	0.895 \| good	7.867 \| good	0.167 \| good
2026-10-08T04:00:00.000Z	29 \| good	4.197 \| good	10.962 \| good	30.607 \| good	0.299 \| good	8.463 \| good	0.251 \| good
2026-10-08T05:00:00.000Z	27 \| good	4.011 \| good	10.079 \| good	29.144 \| good	0.396 \| good	5.175 \| good	0.244 \| good
2026-10-08T06:00:00.000Z	25 \| good	3.795 \| good	9.079 \| good	26.541 \| good	0.255 \| good	6.106 \| good	0.244 \| good
2026-10-08T07:00:00.000Z	30 \| good	3.803 \| good	9.052 \| good	32.157 \| good	0.159 \| good	5.664 \| good	0.201 \| good
2026-10-08T08:00:00.000Z	31 \| good	3.966 \| good	9.049 \| good	33.316 \| good	0.259 \| good	6.147 \| good	0.251 \| good
2026-10-08T09:00:00.000Z	30 \| good	4.041 \| good	9.819 \| good	31.94 \| good	0.273 \| good	6.419 \| good	0.244 \| good
2026-10-08T10:00:00.000Z	26 \| good	4.159 \| good	9.844 \| good	27.505 \| good	0.483 \| good	8.907 \| good	0.243 \| good
2026-10-08T11:00:00.000Z	25 \| good	4.458 \| good	12.502 \| good	26.862 \| good	1.13 \| good	10.853 \| good	0.273 \| good
2026-10-08T12:00:00.000Z	33 \| good	6.082 \| good	33.333 \| good	29.588 \| good	1.097 \| good	11.985 \| good	0.324 \| good
2026-10-08T13:00:00.000Z	33 \| good	6.125 \| good	33.761 \| good	27.106 \| good	1.435 \| good	11.128 \| good	0.284 \| good
2026-10-08T14:00:00.000Z	33 \| good	5.93 \| good	22.989 \| good	26.652 \| good	0.406 \| good	12.079 \| good	0.31 \| good
2026-10-08T15:00:00.000Z	33 \| good	5.567 \| good	22.977 \| good	27.409 \| good	0.384 \| good	8.883 \| good	0.31 \| good
2026-10-08T16:00:00.000Z	37 \| good	6.102 \| good	40.469 \| good	29.626 \| good	0.278 \| good	7.99 \| good	0.295 \| good
2026-10-08T17:00:00.000Z	49 \| good	6.312 \| good	53.436 \| good	31.315 \| good	0.177 \| good	2.522 \| good	0.251 \| good
2026-10-08T18:00:00.000Z	47 \| good	5.897 \| good	50.97 \| good	36.499 \| good	0.18 \| good	2.739 \| good	0.261 \| good
2026-10-08T19:00:00.000Z	56 \| moderate	6.082 \| good	64.971 \| fine	37.744 \| good	0.181 \| good	3.162 \| good	0.272 \| good
2026-10-08T20:00:00.000Z	44 \| good	4.75 \| good	47.789 \| good	39.522 \| good	0.256 \| good	3.482 \| good	0.263 \| good
2026-10-08T21:00:00.000Z	36 \| good	3.744 \| good	32.808 \| good	39.156 \| good	0.164 \| good	2.919 \| good	0.254 \| good
2026-10-08T22:00:00.000Z	37 \| good	3.304 \| good	23.182 \| good	39.603 \| good	0.267 \| good	4.693 \| good	0.254 \| good
2026-10-08T23:00:00.000Z	33 \| good	3.066 \| good	15.332 \| good	36.145 \| good	0.281 \| good	8.96 \| good	0.316 \| good
2026-10-09T00:00:00.000Z	31 \| good	3.204 \| good	12.697 \| good	33.53 \| good	0.222 \| good	14.144 \| good	0.326 \| good
2026-10-09T01:00:00.000Z	24 \| good	4.115 \| good	14.405 \| good	26.327 \| good	0.154 \| good	18.602 \| good	0.329 \| good
2026-10-09T02:00:00.000Z	25 \| good	4.497 \| good	14.483 \| good	26.609 \| good	0.179 \| good	21.662 \| good	0.407 \| good
2026-10-09T03:00:00.000Z	19 \| good	2.545 \| good	10.532 \| good	19.52 \| good	0.425 \| good	5.846 \| good	0.16 \| good
2026-10-09T04:00:00.000Z	27 \| good	4.947 \| good	14.357 \| good	24.796 \| good	0.313 \| good	20.553 \| good	0.296 \| good
2026-10-09T05:00:00.000Z	22 \| good	4.347 \| good	10.02 \| good	21.522 \| good	0.341 \| good	22.618 \| good	0.429 \| good
2026-10-09T06:00:00.000Z	22 \| good	4.32 \| good	9.963 \| good	21.771 \| good	0.499 \| good	19.67 \| good	0.273 \| good
2026-10-09T07:00:00.000Z	22 \| good	4.168 \| good	9.905 \| good	17.646 \| good	0.327 \| good	18.307 \| good	0.287 \| good
2026-10-09T08:00:00.000Z	22 \| good	4.186 \| good	9.101 \| good	12.761 \| good	0.317 \| good	18.178 \| good	0.327 \| good
2026-10-09T09:00:00.000Z	22 \| good	4.199 \| good	9.145 \| good	16.066 \| good	0.392 \| good	20.361 \| good	0.269 \| good
2026-10-09T10:00:00.000Z	22 \| good	4.28 \| good	13.377 \| good	13.537 \| good	0.377 \| good	19.6 \| good	0.348 \| good
2026-10-09T11:00:00.000Z	22 \| good	4.446 \| good	19.46 \| good	14.299 \| good	0.506 \| good	20.028 \| good	0.414 \| good
2026-10-09T12:00:00.000Z	33 \| good	5.049 \| good	35.893 \| good	11.178 \| good	0.342 \| good	18.839 \| good	0.408 \| good
2026-10-09T13:00:00.000Z	33 \| good	5.041 \| good	36.262 \| good	21.051 \| good	0.379 \| good	17.695 \| good	0.36 \| good
2026-10-09T13:00:00.000Z	27 \| good	4.77 \| good	15.296 \| good	11.657 \| good	0.371 \| good	17.561 \| good	0.434 \| good
2026-10-09T12:00:00.000Z	27 \| good	5.175 \| good	22.66 \| good	16.598 \| good	0.443 \| good	5.143 \| good	0.159 \| good
2026-10-09T13:00:00.000Z	19 \| good	3.483 \| good	15.127 \| good	20.3 \| good	0.426 \| good	4.002 \| good	0.163 \| good
2026-10-09T14:00:00.000Z	24 \| good	2.77 \| good	11.724 \| good	26.172 \| good	0.458 \| good	2.465 \| good	0.146 \| good
2026-10-09T15:00:00.000Z	27 \| good	2.36 \| good	9.84 \| good	29.042 \| good	0.488 \| good	1.436 \| good	0.136 \| good
2026-10-09T16:00:00.000Z	28 \| good	3.468 \| good	15.24 \| good	29.971 \| good	0.508 \| good	0.866 \| good	0.132 \| good
2026-10-09T17:00:00.000Z	30 \| good	4.384 \| good	18.829 \| good	32.099 \| good	0.519 \| good	0.657 \| good	0.133 \| good
2026-10-09T18:00:00.000Z	29 \| good	3.314 \| good	14.565 \| good	31.045 \| good	0.536 \| good	0.595 \| good	0.134 \| good
2026-10-09T19:00:00.000Z	27 \| good	2.248 \| good	9.264 \| good	29.389 \| good	0.55 \| good	0.567 \| good	0.136 \| good
2026-10-09T20:00:00.000Z	27 \| good	0.948 \| good	3.656 \| good	28.733 \| good	0.557 \| good	0.621 \| good	0.138 \| good
2026-10-09T21:00:00.000Z	26 \| good	0.364 \| good	1.15 \| good	28.086 \| good	0.556 \| good	0.955 \| good	0.143 \| good
2026-10-09T22:00:00.000Z	23 \| good	0.399 \| good	1.636 \| good	24.825 \| good	0.549 \| good	2.12 \| good	0.156 \| good
2026-10-09T23:00:00.000Z	20 \| good	0.957 \| good	3.639 \| good	22.461 \| good	0.556 \| good	4.556 \| good	0.18 \| good
2026-10-10T00:00:00.000Z	19 \| good	1.984 \| good	8.272 \| good	21.289 \| good	0.581 \| good	5.767 \| good	0.188 \| good
2026-10-10T01:00:00.000Z	17 \| good	1.769 \| good	7.253 \| good	18.459 \| good	0.598 \| good	5.673 \| good	0.182 \| good
2026-10-10T02:00:00.000Z	17 \| good	2.321 \| good	9.524 \| good	18.281 \| good	0.614 \| good	6.011 \| good	0.182 \| good
2026-10-10T03:00:00.000Z	16 \| good	2.687 \| good	11.189 \| good	17.474 \| good	0.618 \| good	6.228 \| good	0.183 \| good
2026-10-10T04:00:00.000Z	16 \| good	2.803 \| good	11.79 \| good	16.108 \| good	0.603 \| good	5.527 \| good	0.18 \| good
2026-10-10T05:00:00.000Z	16 \| good	3.406 \| good	14.855 \| good	15.423 \| good	0.59 \| good	4.624 \| good	0.175 \| good
2026-10-10T06:00:00.000Z	22 \| good	3.575 \| good	15.798 \| good	15.593 \| good	0.593 \| good	4.342 \| good	0.173 \| good
2026-10-10T07:00:00.000Z	22 \| good	3.701 \| good	16.334 \| good	16.414 \| good	0.602 \| good	4.449 \| good	0.173 \| good
2026-10-10T08:00:00.000Z	22 \| good	3.881 \| good	17.223 \| good	16.581 \| good	0.609 \| good	4.751 \| good	0.175 \| good
2026-10-10T09:00:00.000Z	22 \| good	4.102 \| good	18.029 \| good	14.39 \| good	0.612 \| good	5.152 \| good	0.179 \| good
2026-10-10T10:00:00.000Z	22 \| good	4.17 \| good	18.312 \| good	14.259 \| good	0.613 \| good	5.89 \| good	0.184 \| good
2026-10-10T11:00:00.000Z	27 \| good	5.256 \| good	23.078 \| good	13.943 \| good	0.62 \| good	7.632 \| good	0.198 \| good
2026-10-10T12:00:00.000Z	22 \| good	4.093 \| good	17.742 \| good	13.57 \| good	0.632 \| good	8.79 \| good	0.227 \| good
2026-10-10T13:00:00.000Z	22 \| good	4.192 \| good	18.374 \| good	16.658 \| good	0.545 \| good	5.525 \| good	0.217 \| good
2026-10-10T14:00:00.000Z	19 \| good	3.028 \| good	12.882 \| good	20.712 \| good	0.509 \| good	2.223 \| good	0.169 \| good
2026-10-10T15:00:00.000Z	21 \| good	1.157 \| good	4.725 \| good	23.306 \| good	0.446 \| good	1.294 \| good	0.156 \| good
2026-10-10T16:00:00.000Z	22 \| good	0.616 \| good	2.176 \| good	24.481 \| good	0.413 \| good	0.925 \| good	0.151 \| good
2026-10-10T17:00:00.000Z	23 \| good	0.521 \| good	2.027 \| good	25.217 \| good	0.396 \| good	0.76 \| good	0.148 \| good
2026-10-10T18:00:00.000Z	23 \| good	1.193 \| good	4.746 \| good	24.967 \| good	0.391 \| good	0.711 \| good	0.146 \| good
2026-10-10T19:00:00.000Z	22 \| good	0.912 \| good	3.421 \| good	24.354 \| good	0.392 \| good	0.748 \| good	0.146 \| good
2026-10-10T20:00:00.000Z	21 \| good	1.449 \| good	5.75 \| good	22.63 \| good	0.398 \| good	0.881 \| good	0.146 \| good
2026-10-10T21:00:00.000Z	19 \| good	1.802 \| good	7.245 \| good	21.386 \| good	0.393 \| good	1.836 \| good	0.158 \| good
2026-10-10T22:00:00.000Z	19 \| good	2.02 \| good	8.478 \| good	21.161 \| good	0.429 \| good	6.916 \| good	0.211 \| good
2026-10-10T23:00:00.000Z	19 \| good	2.95 \| good	12.455 \| good	20.484 \| good	0.519 \| good	13.928 \| good	0.275 \| good
2026-10-11T00:00:00.000Z	20 \| good	3.35 \| good	14.601 \| good	21.944 \| good	0.622 \| good	18.967 \| good	0.324 \| good
2026-10-11T01:00:00.000Z	22 \| good	3.996 \| good	17.248 \| good	19.582 \| good	0.719 \| good	21.291 \| good	0.349 \| good
2026-10-11T02:00:00.000Z	33 \| good	5.518 \| good	24.264 \| good	19.188 \| good	0.792 \| good	22.567 \| good	0.352 \| good
2026-10-11T03:00:00.000Z	33 \| good	6.136 \| good	26.789 \| good	18.113 \| good	0.855 \| good	22.439 \| good	0.338 \| good
2026-10-11T04:00:00.000Z	33 \| good	6.353 \| good	28.188 \| good	16.602 \| good	0.929 \| good	21.998 \| good	0.319 \| good
2026-10-11T05:00:00.000Z	38 \| good	6.779 \| good	30.008 \| good	14.937 \| good	1.003 \| good	21.577 \| good	0.306 \| good
2026-10-11T06:00:00.000Z	38 \| good	6.692 \| good	29.725 \| good	14.562 \| good	1.085 \| good	21.096 \| good	0.296 \| good
2026-10-11T07:00:00.000Z	44 \| good	7.595 \| good	33.306 \| good	13.851 \| good	1.152 \| good	20.535 \| good	0.286 \| good
2026-10-11T08:00:00.000Z	44 \| good	8.135 \| good	35.815 \| good	12.607 \| good	1.193 \| good	19.772 \| good	0.274 \| good
2026-10-11T09:00:00.000Z	49 \| good	9.212 \| good	40.889 \| good	13.631 \| good	1.213 \| good	18.945 \| good	0.26 \| good
2026-10-11T10:00:00.000Z	49 \| good	8.902 \| good	39.099 \| good	13.729 \| good	1.209 \| good	18.292 \| good	0.252 \| good
2026-10-11T11:00:00.000Z	54 \| moderate	11.11 \| good	48.91 \| good	13.72 \| good	1.191 \| good	17.936 \| good	0.252 \| good

Live air quality index in Connecticut, USA today

Major air pollutants in Connecticut, USA

Particulate Matter2.5 (PM2.5)

Particulate Matter10 (PM10)

Ozone (O3)

Sulfur Dioxide (SO2)

Nitrogen Dioxide (NO2)

Carbon Monoxide (CO)

Track live Connecticut, USA air quality forecast and history

Get reliable air quality data to drive your business

Connecticut, USA air quality map: Stay updated on AQI near you

Air quality in cities of Connecticut, USA

Air quality in nearby states

New York, USA

Rhode Island, USA

Massachusetts, USA

New Jersey, USA

New Hampshire, USA

Vermont, USA

How accurate is Connecticut, USA air quality data?

Air quality levels in US

Frequently asked questions

How often is air quality information updated for Connecticut, USA?

What time in the last 24 hours was the air quality in Connecticut, USA at its worst?

When did Connecticut, USA experience the best air quality in the last 24 hours?

What is the AQI in Connecticut, USA right now?

What is the most common type of pollution in Connecticut, USA?

What should I do in case of poor air quality in Connecticut, USA?

What is the PM2.5 level in Connecticut, USA at the moment?

What is the PM10 level in Connecticut, USA at the moment?

What is the carbon monoxide (CO) level in Connecticut, USA at the moment?

What is the sulfur dioxide (SO2) level in Connecticut, USA at the moment?

What is the ozone (O3) level in Connecticut, USA at the moment?

What is the nitrogen dioxide (NO2) level in Connecticut, USA at the moment?

Particulate Matter_2.5 (PM_2.5)

Particulate Matter₁₀ (PM₁₀)

Ozone (O₃)

Sulfur Dioxide (SO₂)

Nitrogen Dioxide (NO₂)

What is the PM_2.5 level in Connecticut, USA at the moment?

What is the PM₁₀ level in Connecticut, USA at the moment?

What is the sulfur dioxide (SO₂) level in Connecticut, USA at the moment?

What is the ozone (O₃) level in Connecticut, USA at the moment?

What is the nitrogen dioxide (NO₂) level in Connecticut, USA at the moment?