What is the sulfur dioxide (SO2) level in Waltham, Massachusetts at the moment?

Currently, Waltham, Massachusetts has a sulfur dioxide (SO2) concentration of 0.494 ppb.

What is the ozone (O3) level in Waltham, Massachusetts at the moment?

The current ozone (O3) level in Waltham, Massachusetts at the moment is 14.862 ppm.

What is the nitrogen dioxide (NO2) level in Waltham, Massachusetts at the moment?

Nitrogen dioxide (NO2) level in Waltham, Massachusetts at the moment is 9.891 ppb.

Live air quality index in Waltham, Massachusetts today

Name: Live air pollution levels in Waltham, Massachusetts today
Creator: Ambee

Stay updated with real-time air quality in Waltham, Massachusetts 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)

Moderate

Waltham, Massachusetts

Last updated: ... (Local time)

Major air pollutants in Waltham, Massachusetts

Good

Fine

Moderate

Poor

Very poor

Hazardous

Particulate Matter_2.5 (PM_2.5)

9.81 μg/m³

12.1

35.5

55.5

250.5

500.5+

Particulate Matter₁₀ (PM₁₀)

42.77 μg/m³

155

255

425

605+

Ozone (O₃)

26.10 ppb

201

201+

Sulfur Dioxide (SO₂)

0.49 ppb

186

605

1005+

Nitrogen Dioxide (NO₂)

16.17 ppb

101

361

1250

2050+

Carbon Monoxide (CO)

0.50 ppm

4.5

9.5

12.5

230.5

50.5+

Pollen Level

Moderate

Waltham, Massachusetts

Get Live Pollen Counts

Waltham, Massachusetts

Scroll To Air Quality Map

Track live Waltham, Massachusetts air quality forecast and history

Time	AQI	PM_2.5	PM₁₀	O₃	SO₂	NO₂	CO
2025-09-13T09:00:00.000Z	38 \| good	7.216 \| good	34.271 \| good	7.189 \| good	0.424 \| good	7.238 \| good	0.276 \| good
2025-09-13T10:00:00.000Z	38 \| good	6.508 \| good	18.441 \| good	5.436 \| good	0.425 \| good	8.002 \| good	0.278 \| good
2025-09-13T11:00:00.000Z	38 \| good	6.554 \| good	16.84 \| good	5.475 \| good	0.417 \| good	7.632 \| good	0.3 \| good
2025-09-13T12:00:00.000Z	33 \| good	6.158 \| good	17.972 \| good	5.927 \| good	0.523 \| good	10.565 \| good	0.389 \| good
2025-09-13T13:00:00.000Z	38 \| good	6.513 \| good	29.333 \| good	12.322 \| good	0.604 \| good	10.337 \| good	0.333 \| good
2025-09-13T14:00:00.000Z	33 \| good	6.432 \| good	25.208 \| good	12.345 \| good	0.511 \| good	9.656 \| good	0.232 \| good
2025-09-13T15:00:00.000Z	33 \| good	6.055 \| good	25.853 \| good	23.657 \| good	0.42 \| good	6.466 \| good	0.188 \| good
2025-09-13T16:00:00.000Z	33 \| good	5.915 \| good	24.87 \| good	21.917 \| good	0.362 \| good	4.838 \| good	0.188 \| good
2025-09-13T17:00:00.000Z	33 \| good	5.986 \| good	25.753 \| good	28.254 \| good	0.549 \| good	3.614 \| good	0.188 \| good
2025-09-13T18:00:00.000Z	33 \| good	5.899 \| good	15.539 \| good	30.778 \| good	0.464 \| good	3.377 \| good	0.188 \| good
2025-09-13T19:00:00.000Z	34 \| good	5.83 \| good	36.892 \| good	32.665 \| good	0.462 \| good	3.571 \| good	0.188 \| good
2025-09-13T20:00:00.000Z	38 \| good	6.947 \| good	31.778 \| good	29.782 \| good	0.427 \| good	5.622 \| good	0.222 \| good
2025-09-13T21:00:00.000Z	38 \| good	6.679 \| good	15.072 \| good	32.938 \| good	0.485 \| good	11.371 \| good	0.255 \| good
2025-09-13T22:00:00.000Z	38 \| good	6.71 \| good	30.82 \| good	32.491 \| good	0.493 \| good	8.39 \| good	0.255 \| good
2025-09-13T23:00:00.000Z	33 \| good	6.27 \| good	26.817 \| good	33.265 \| good	0.444 \| good	5.423 \| good	0.2 \| good
2025-09-14T00:00:00.000Z	33 \| good	6.077 \| good	26.006 \| good	33.097 \| good	0.405 \| good	5.248 \| good	0.244 \| good
2025-09-14T01:00:00.000Z	33 \| good	6.207 \| good	24.481 \| good	29.622 \| good	0.409 \| good	6.264 \| good	0.234 \| good
2025-09-14T02:00:00.000Z	33 \| good	6.085 \| good	20.286 \| good	33.147 \| good	0.461 \| good	5.886 \| good	0.234 \| good
2025-09-14T03:00:00.000Z	23 \| good	3.217 \| good	14.161 \| good	25.429 \| good	0.926 \| good	8.081 \| good	0.177 \| good
2025-09-14T04:00:00.000Z	33 \| good	5.634 \| good	19.374 \| good	27.742 \| good	0.451 \| good	5.85 \| good	0.301 \| good
2025-09-14T05:00:00.000Z	33 \| good	5.55 \| good	23.679 \| good	24.593 \| good	0.358 \| good	5.023 \| good	0.234 \| good
2025-09-14T06:00:00.000Z	27 \| good	5.312 \| good	20.822 \| good	22.759 \| good	0.415 \| good	3.03 \| good	0.234 \| good
2025-09-14T07:00:00.000Z	27 \| good	5.154 \| good	22.109 \| good	23.67 \| good	0.421 \| good	3.033 \| good	0.267 \| good
2025-09-14T08:00:00.000Z	27 \| good	5.194 \| good	22.221 \| good	19.696 \| good	0.453 \| good	6.883 \| good	0.267 \| good
2025-09-14T09:00:00.000Z	27 \| good	5.335 \| good	21.022 \| good	21.213 \| good	0.398 \| good	3.186 \| good	0.234 \| good
2025-09-14T10:00:00.000Z	27 \| good	5.47 \| good	18.008 \| good	20.676 \| good	0.395 \| good	3.914 \| good	0.222 \| good
2025-09-14T11:00:00.000Z	33 \| good	5.571 \| good	25.378 \| good	15.92 \| good	0.385 \| good	4.577 \| good	0.232 \| good
2025-09-14T12:00:00.000Z	33 \| good	5.908 \| good	26.763 \| good	21.637 \| good	0.383 \| good	7.498 \| good	0.255 \| good
2025-09-14T13:00:00.000Z	33 \| good	5.848 \| good	24.968 \| good	19.837 \| good	0.389 \| good	7.928 \| good	0.345 \| good
2025-09-14T14:00:00.000Z	33 \| good	5.845 \| good	17.678 \| good	13.139 \| good	0.383 \| good	4.423 \| good	0.278 \| good
2025-09-14T15:00:00.000Z	33 \| good	6.168 \| good	22.357 \| good	20.989 \| good	0.413 \| good	3.869 \| good	0.267 \| good
2025-09-14T16:00:00.000Z	38 \| good	7.02 \| good	30.797 \| good	24.961 \| good	0.411 \| good	2.787 \| good	0.234 \| good
2025-09-14T17:00:00.000Z	38 \| good	6.713 \| good	27.076 \| good	33.576 \| good	0.42 \| good	1.98 \| good	0.2 \| good
2025-09-14T18:00:00.000Z	38 \| good	6.747 \| good	12.954 \| good	39.844 \| good	0.438 \| good	2.964 \| good	0.234 \| good
2025-09-14T19:00:00.000Z	44 \| good	8.072 \| good	28.531 \| good	39.799 \| good	0.473 \| good	4.925 \| good	0.234 \| good
2025-09-14T20:00:00.000Z	40 \| good	7.371 \| good	27.956 \| good	43.31 \| good	0.524 \| good	7.558 \| good	0.244 \| good
2025-09-14T21:00:00.000Z	49 \| good	8.974 \| good	39.882 \| good	41.224 \| good	0.523 \| good	6.065 \| good	0.244 \| good
2025-09-14T22:00:00.000Z	49 \| good	8.957 \| good	36.199 \| good	39.034 \| good	0.515 \| good	6.663 \| good	0.244 \| good
2025-09-14T23:00:00.000Z	49 \| good	9.075 \| good	48.794 \| good	37.392 \| good	0.621 \| good	8.902 \| good	0.221 \| good
2025-09-15T00:00:00.000Z	49 \| good	9.213 \| good	39.82 \| good	33.83 \| good	0.511 \| good	10.119 \| good	0.309 \| good
2025-09-15T01:00:00.000Z	49 \| good	9.349 \| good	41.076 \| good	26.863 \| good	0.498 \| good	14.558 \| good	0.353 \| good
2025-09-15T02:00:00.000Z	52 \| moderate	9.898 \| good	35.664 \| good	28.043 \| good	0.492 \| good	15.106 \| good	0.464 \| good
2025-09-15T03:00:00.000Z	52 \| moderate	9.659 \| good	40.898 \| good	17.114 \| good	0.512 \| good	15.029 \| good	0.622 \| good
2025-09-15T04:00:00.000Z	54 \| moderate	10.861 \| good	27.637 \| good	15.506 \| good	0.476 \| good	15.572 \| good	0.669 \| good
2025-09-15T05:00:00.000Z	54 \| moderate	11.172 \| good	39.537 \| good	14.521 \| good	0.461 \| good	13.589 \| good	0.645 \| good
2025-09-15T06:00:00.000Z	54 \| moderate	10.866 \| good	49.004 \| good	17.502 \| good	0.535 \| good	18.036 \| good	0.534 \| good
2025-09-15T07:00:00.000Z	52 \| moderate	9.813 \| good	42.768 \| good	26.101 \| good	0.491 \| good	16.169 \| good	0.5 \| good
2025-09-15T08:00:00.000Z	52 \| moderate	9.813 \| good	42.768 \| good	26.101 \| good	0.491 \| good	16.169 \| good	0.5 \| good
2025-09-11T16:00:00.000Z	39 \| good	5.77 \| good	25.222 \| good	42.316 \| good	1.194 \| good	3.859 \| good	0.179 \| good
2025-09-11T17:00:00.000Z	43 \| good	3.923 \| good	17.217 \| good	45.754 \| good	1.035 \| good	2.958 \| good	0.169 \| good
2025-09-11T18:00:00.000Z	42 \| good	4.593 \| good	20.039 \| good	44.852 \| good	0.877 \| good	2.057 \| good	0.158 \| good
2025-09-11T19:00:00.000Z	42 \| good	5.022 \| good	21.75 \| good	45.387 \| good	0.937 \| good	2.58 \| good	0.161 \| good
2025-09-11T20:00:00.000Z	39 \| good	5.262 \| good	22.976 \| good	41.746 \| good	0.997 \| good	3.103 \| good	0.164 \| good
2025-09-11T21:00:00.000Z	33 \| good	5.992 \| good	26.457 \| good	35.126 \| good	1.057 \| good	3.627 \| good	0.167 \| good
2025-09-11T22:00:00.000Z	44 \| good	8.123 \| good	35.746 \| good	26.67 \| good	1.182 \| good	10.868 \| good	0.227 \| good
2025-09-11T23:00:00.000Z	49 \| good	9.217 \| good	40.638 \| good	17.695 \| good	1.306 \| good	18.109 \| good	0.287 \| good
2025-09-12T00:00:00.000Z	52 \| moderate	10.113 \| good	44.931 \| good	16.824 \| good	1.431 \| good	25.351 \| good	0.347 \| good
2025-09-12T01:00:00.000Z	58 \| moderate	12.984 \| fine	58.052 \| fine	17.138 \| good	1.407 \| good	24.65 \| good	0.348 \| good
2025-09-12T02:00:00.000Z	62 \| moderate	15.022 \| fine	67.454 \| fine	10.842 \| good	1.383 \| good	23.95 \| good	0.349 \| good
2025-09-12T03:00:00.000Z	64 \| moderate	15.817 \| fine	70.426 \| fine	6.246 \| good	1.359 \| good	23.249 \| good	0.35 \| good
2025-09-12T04:00:00.000Z	56 \| moderate	12.397 \| fine	55.837 \| fine	13.041 \| good	1.104 \| good	16.909 \| good	0.295 \| good
2025-09-12T05:00:00.000Z	54 \| moderate	11.247 \| good	50.041 \| good	18.798 \| good	0.849 \| good	10.569 \| good	0.239 \| good
2025-09-12T06:00:00.000Z	52 \| moderate	9.657 \| good	43.104 \| good	19.933 \| good	0.594 \| good	4.229 \| good	0.184 \| good
2025-09-12T07:00:00.000Z	49 \| good	9.443 \| good	42.096 \| good	18.784 \| good	0.623 \| good	3.927 \| good	0.178 \| good
2025-09-12T08:00:00.000Z	54 \| moderate	10.863 \| good	48.084 \| good	16.269 \| good	0.653 \| good	3.624 \| good	0.171 \| good
2025-09-12T09:00:00.000Z	27 \| good	5.477 \| good	23.228 \| good	9.695 \| good	0.682 \| good	3.321 \| good	0.165 \| good
2025-09-12T10:00:00.000Z	38 \| good	6.65 \| good	29.749 \| good	4.762 \| good	0.744 \| good	4.314 \| good	0.176 \| good
2025-09-12T11:00:00.000Z	33 \| good	6.327 \| good	28.49 \| good	7.21 \| good	0.805 \| good	5.307 \| good	0.186 \| good
2025-09-12T12:00:00.000Z	27 \| good	5.457 \| good	23.294 \| good	13.947 \| good	0.867 \| good	6.3 \| good	0.197 \| good
2025-09-12T13:00:00.000Z	27 \| good	4.529 \| good	19.267 \| good	18.734 \| good	0.772 \| good	5.05 \| good	0.183 \| good
2025-09-12T14:00:00.000Z	22 \| good	3.839 \| good	16.935 \| good	20.279 \| good	0.678 \| good	3.799 \| good	0.17 \| good
2025-09-12T15:00:00.000Z	23 \| good	4.479 \| good	19.163 \| good	24.783 \| good	0.584 \| good	2.548 \| good	0.156 \| good
2025-09-12T16:00:00.000Z	33 \| good	6.262 \| good	27.865 \| good	29.398 \| good	0.569 \| good	2.334 \| good	0.154 \| good
2025-09-12T17:00:00.000Z	38 \| good	6.503 \| good	29.031 \| good	35.415 \| good	0.554 \| good	2.119 \| good	0.153 \| good
2025-09-12T18:00:00.000Z	38 \| good	6.852 \| good	30.104 \| good	39.817 \| good	0.54 \| good	1.904 \| good	0.151 \| good
2025-09-12T19:00:00.000Z	38 \| good	6.574 \| good	29.037 \| good	37.632 \| good	0.59 \| good	2.376 \| good	0.153 \| good
2025-09-12T20:00:00.000Z	38 \| good	6.527 \| good	29.103 \| good	29.833 \| good	0.641 \| good	2.847 \| good	0.156 \| good
2025-09-12T21:00:00.000Z	33 \| good	5.981 \| good	25.929 \| good	24.586 \| good	0.691 \| good	3.319 \| good	0.158 \| good
2025-09-12T22:00:00.000Z	27 \| good	5.096 \| good	21.848 \| good	17.08 \| good	0.812 \| good	7.84 \| good	0.187 \| good
2025-09-12T23:00:00.000Z	27 \| good	5.05 \| good	21.581 \| good	10.438 \| good	0.932 \| good	12.36 \| good	0.216 \| good
2025-09-13T00:00:00.000Z	27 \| good	4.616 \| good	20.297 \| good	8.955 \| good	1.052 \| good	16.881 \| good	0.245 \| good
2025-09-13T01:00:00.000Z	27 \| good	4.964 \| good	21.495 \| good	10.298 \| good	1.114 \| good	18.74 \| good	0.255 \| good
2025-09-13T02:00:00.000Z	22 \| good	3.724 \| good	16.118 \| good	11.308 \| good	1.176 \| good	20.599 \| good	0.265 \| good
2025-09-13T03:00:00.000Z	22 \| good	4.178 \| good	18.131 \| good	9.992 \| good	1.238 \| good	22.459 \| good	0.276 \| good
2025-09-13T04:00:00.000Z	33 \| good	5.615 \| good	24.198 \| good	10.248 \| good	1.257 \| good	22.84 \| good	0.283 \| good
2025-09-13T05:00:00.000Z	33 \| good	5.888 \| good	25.335 \| good	10.234 \| good	1.277 \| good	23.222 \| good	0.291 \| good
2025-09-13T06:00:00.000Z	33 \| good	5.511 \| good	23.967 \| good	10.5 \| good	1.297 \| good	23.604 \| good	0.299 \| good
2025-09-13T07:00:00.000Z	27 \| good	4.713 \| good	20.659 \| good	12.02 \| good	1.363 \| good	21.938 \| good	0.285 \| good
2025-09-13T08:00:00.000Z	22 \| good	4.314 \| good	18.928 \| good	11.786 \| good	1.429 \| good	20.272 \| good	0.272 \| good
2025-09-13T09:00:00.000Z	22 \| good	4.27 \| good	18.795 \| good	10.468 \| good	1.495 \| good	18.606 \| good	0.258 \| good
2025-09-13T10:00:00.000Z	22 \| good	4.5 \| good	19.23 \| good	10.199 \| good	1.582 \| good	17.613 \| good	0.278 \| good
2025-09-13T11:00:00.000Z	27 \| good	4.753 \| good	20.586 \| good	10.273 \| good	1.67 \| good	16.621 \| good	0.298 \| good
2025-09-13T12:00:00.000Z	22 \| good	3.974 \| good	17.747 \| good	14.712 \| good	1.757 \| good	15.629 \| good	0.318 \| good
2025-09-13T13:00:00.000Z	22 \| good	4.306 \| good	18.816 \| good	20.372 \| good	1.682 \| good	13.028 \| good	0.272 \| good
2025-09-13T14:00:00.000Z	33 \| good	5.6 \| good	23.997 \| good	27.243 \| good	1.607 \| good	10.428 \| good	0.225 \| good
2025-09-13T15:00:00.000Z	44 \| good	8.041 \| good	35.024 \| good	34.151 \| good	1.532 \| good	7.827 \| good	0.179 \| good

Waltham

Get reliable air quality data to drive your business

Waltham, Massachusetts air quality map: Stay updated on AQI near you

0.24ppm

How accurate is Massachusetts, USA air quality data?

Air quality and pollutant data for Massachusetts, 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

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Frequently asked questions

How often is air quality information updated for Waltham, Massachusetts?

The air quality information for Waltham, Massachusetts is updated every hour for accuracy.

What time in the last 24 hours was the air quality in Waltham, Massachusetts at its worst?

In the past 24 hours, the air quality in Waltham, Massachusetts was at its worst at 02:00:00 on 2025-09-11.

When did Waltham, Massachusetts experience the best air quality in the last 24 hours?

In the last 24 hours, the best air quality in Waltham, Massachusetts was observed at 11:00:00 on 2025-09-11.

What is the AQI in Waltham, Massachusetts right now?

As of now, the AQI in Waltham, Massachusetts is 27, indicating Good conditions.

What is the most common type of pollution in Waltham, Massachusetts?

Waltham, Massachusetts air has the highest levels of PM2.5.

What should I do in case of poor air quality in Waltham, Massachusetts?

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

What is the PM_2.5 level in Waltham, Massachusetts at the moment?

PM_2.5 levels in Waltham, Massachusetts are currently 4.998 μg/m³.

What is the PM₁₀ level in Waltham, Massachusetts at the moment?

The PM₁₀ concentration in Waltham, Massachusetts is 21.885 μg/m³ at the moment.

What is the carbon monoxide (CO) level in Waltham, Massachusetts at the moment?

The current carbon monoxide (CO) concentration in Waltham, Massachusetts is 0.254 ppm.

What is the sulfur dioxide (SO₂) level in Waltham, Massachusetts at the moment?

Currently, Waltham, Massachusetts has a sulfur dioxide (SO₂) concentration of 0.494 ppb.

What is the ozone (O₃) level in Waltham, Massachusetts at the moment?

The current ozone (O₃) level in Waltham, Massachusetts at the moment is 14.862 ppm.

What is the nitrogen dioxide (NO₂) level in Waltham, Massachusetts at the moment?

Nitrogen dioxide (NO₂) level in Waltham, Massachusetts at the moment is 9.891 ppb.

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Time	AQI	PM_2.5	PM₁₀	O₃	SO₂	NO₂	CO
2025-09-13T09:00:00.000Z	38 \| good	7.216 \| good	34.271 \| good	7.189 \| good	0.424 \| good	7.238 \| good	0.276 \| good
2025-09-13T10:00:00.000Z	38 \| good	6.508 \| good	18.441 \| good	5.436 \| good	0.425 \| good	8.002 \| good	0.278 \| good
2025-09-13T11:00:00.000Z	38 \| good	6.554 \| good	16.84 \| good	5.475 \| good	0.417 \| good	7.632 \| good	0.3 \| good
2025-09-13T12:00:00.000Z	33 \| good	6.158 \| good	17.972 \| good	5.927 \| good	0.523 \| good	10.565 \| good	0.389 \| good
2025-09-13T13:00:00.000Z	38 \| good	6.513 \| good	29.333 \| good	12.322 \| good	0.604 \| good	10.337 \| good	0.333 \| good
2025-09-13T14:00:00.000Z	33 \| good	6.432 \| good	25.208 \| good	12.345 \| good	0.511 \| good	9.656 \| good	0.232 \| good
2025-09-13T15:00:00.000Z	33 \| good	6.055 \| good	25.853 \| good	23.657 \| good	0.42 \| good	6.466 \| good	0.188 \| good
2025-09-13T16:00:00.000Z	33 \| good	5.915 \| good	24.87 \| good	21.917 \| good	0.362 \| good	4.838 \| good	0.188 \| good
2025-09-13T17:00:00.000Z	33 \| good	5.986 \| good	25.753 \| good	28.254 \| good	0.549 \| good	3.614 \| good	0.188 \| good
2025-09-13T18:00:00.000Z	33 \| good	5.899 \| good	15.539 \| good	30.778 \| good	0.464 \| good	3.377 \| good	0.188 \| good
2025-09-13T19:00:00.000Z	34 \| good	5.83 \| good	36.892 \| good	32.665 \| good	0.462 \| good	3.571 \| good	0.188 \| good
2025-09-13T20:00:00.000Z	38 \| good	6.947 \| good	31.778 \| good	29.782 \| good	0.427 \| good	5.622 \| good	0.222 \| good
2025-09-13T21:00:00.000Z	38 \| good	6.679 \| good	15.072 \| good	32.938 \| good	0.485 \| good	11.371 \| good	0.255 \| good
2025-09-13T22:00:00.000Z	38 \| good	6.71 \| good	30.82 \| good	32.491 \| good	0.493 \| good	8.39 \| good	0.255 \| good
2025-09-13T23:00:00.000Z	33 \| good	6.27 \| good	26.817 \| good	33.265 \| good	0.444 \| good	5.423 \| good	0.2 \| good
2025-09-14T00:00:00.000Z	33 \| good	6.077 \| good	26.006 \| good	33.097 \| good	0.405 \| good	5.248 \| good	0.244 \| good
2025-09-14T01:00:00.000Z	33 \| good	6.207 \| good	24.481 \| good	29.622 \| good	0.409 \| good	6.264 \| good	0.234 \| good
2025-09-14T02:00:00.000Z	33 \| good	6.085 \| good	20.286 \| good	33.147 \| good	0.461 \| good	5.886 \| good	0.234 \| good
2025-09-14T03:00:00.000Z	23 \| good	3.217 \| good	14.161 \| good	25.429 \| good	0.926 \| good	8.081 \| good	0.177 \| good
2025-09-14T04:00:00.000Z	33 \| good	5.634 \| good	19.374 \| good	27.742 \| good	0.451 \| good	5.85 \| good	0.301 \| good
2025-09-14T05:00:00.000Z	33 \| good	5.55 \| good	23.679 \| good	24.593 \| good	0.358 \| good	5.023 \| good	0.234 \| good
2025-09-14T06:00:00.000Z	27 \| good	5.312 \| good	20.822 \| good	22.759 \| good	0.415 \| good	3.03 \| good	0.234 \| good
2025-09-14T07:00:00.000Z	27 \| good	5.154 \| good	22.109 \| good	23.67 \| good	0.421 \| good	3.033 \| good	0.267 \| good
2025-09-14T08:00:00.000Z	27 \| good	5.194 \| good	22.221 \| good	19.696 \| good	0.453 \| good	6.883 \| good	0.267 \| good
2025-09-14T09:00:00.000Z	27 \| good	5.335 \| good	21.022 \| good	21.213 \| good	0.398 \| good	3.186 \| good	0.234 \| good
2025-09-14T10:00:00.000Z	27 \| good	5.47 \| good	18.008 \| good	20.676 \| good	0.395 \| good	3.914 \| good	0.222 \| good
2025-09-14T11:00:00.000Z	33 \| good	5.571 \| good	25.378 \| good	15.92 \| good	0.385 \| good	4.577 \| good	0.232 \| good
2025-09-14T12:00:00.000Z	33 \| good	5.908 \| good	26.763 \| good	21.637 \| good	0.383 \| good	7.498 \| good	0.255 \| good
2025-09-14T13:00:00.000Z	33 \| good	5.848 \| good	24.968 \| good	19.837 \| good	0.389 \| good	7.928 \| good	0.345 \| good
2025-09-14T14:00:00.000Z	33 \| good	5.845 \| good	17.678 \| good	13.139 \| good	0.383 \| good	4.423 \| good	0.278 \| good
2025-09-14T15:00:00.000Z	33 \| good	6.168 \| good	22.357 \| good	20.989 \| good	0.413 \| good	3.869 \| good	0.267 \| good
2025-09-14T16:00:00.000Z	38 \| good	7.02 \| good	30.797 \| good	24.961 \| good	0.411 \| good	2.787 \| good	0.234 \| good
2025-09-14T17:00:00.000Z	38 \| good	6.713 \| good	27.076 \| good	33.576 \| good	0.42 \| good	1.98 \| good	0.2 \| good
2025-09-14T18:00:00.000Z	38 \| good	6.747 \| good	12.954 \| good	39.844 \| good	0.438 \| good	2.964 \| good	0.234 \| good
2025-09-14T19:00:00.000Z	44 \| good	8.072 \| good	28.531 \| good	39.799 \| good	0.473 \| good	4.925 \| good	0.234 \| good
2025-09-14T20:00:00.000Z	40 \| good	7.371 \| good	27.956 \| good	43.31 \| good	0.524 \| good	7.558 \| good	0.244 \| good
2025-09-14T21:00:00.000Z	49 \| good	8.974 \| good	39.882 \| good	41.224 \| good	0.523 \| good	6.065 \| good	0.244 \| good
2025-09-14T22:00:00.000Z	49 \| good	8.957 \| good	36.199 \| good	39.034 \| good	0.515 \| good	6.663 \| good	0.244 \| good
2025-09-14T23:00:00.000Z	49 \| good	9.075 \| good	48.794 \| good	37.392 \| good	0.621 \| good	8.902 \| good	0.221 \| good
2025-09-15T00:00:00.000Z	49 \| good	9.213 \| good	39.82 \| good	33.83 \| good	0.511 \| good	10.119 \| good	0.309 \| good
2025-09-15T01:00:00.000Z	49 \| good	9.349 \| good	41.076 \| good	26.863 \| good	0.498 \| good	14.558 \| good	0.353 \| good
2025-09-15T02:00:00.000Z	52 \| moderate	9.898 \| good	35.664 \| good	28.043 \| good	0.492 \| good	15.106 \| good	0.464 \| good
2025-09-15T03:00:00.000Z	52 \| moderate	9.659 \| good	40.898 \| good	17.114 \| good	0.512 \| good	15.029 \| good	0.622 \| good
2025-09-15T04:00:00.000Z	54 \| moderate	10.861 \| good	27.637 \| good	15.506 \| good	0.476 \| good	15.572 \| good	0.669 \| good
2025-09-15T05:00:00.000Z	54 \| moderate	11.172 \| good	39.537 \| good	14.521 \| good	0.461 \| good	13.589 \| good	0.645 \| good
2025-09-15T06:00:00.000Z	54 \| moderate	10.866 \| good	49.004 \| good	17.502 \| good	0.535 \| good	18.036 \| good	0.534 \| good
2025-09-15T07:00:00.000Z	52 \| moderate	9.813 \| good	42.768 \| good	26.101 \| good	0.491 \| good	16.169 \| good	0.5 \| good
2025-09-15T08:00:00.000Z	52 \| moderate	9.813 \| good	42.768 \| good	26.101 \| good	0.491 \| good	16.169 \| good	0.5 \| good
2025-09-11T16:00:00.000Z	39 \| good	5.77 \| good	25.222 \| good	42.316 \| good	1.194 \| good	3.859 \| good	0.179 \| good
2025-09-11T17:00:00.000Z	43 \| good	3.923 \| good	17.217 \| good	45.754 \| good	1.035 \| good	2.958 \| good	0.169 \| good
2025-09-11T18:00:00.000Z	42 \| good	4.593 \| good	20.039 \| good	44.852 \| good	0.877 \| good	2.057 \| good	0.158 \| good
2025-09-11T19:00:00.000Z	42 \| good	5.022 \| good	21.75 \| good	45.387 \| good	0.937 \| good	2.58 \| good	0.161 \| good
2025-09-11T20:00:00.000Z	39 \| good	5.262 \| good	22.976 \| good	41.746 \| good	0.997 \| good	3.103 \| good	0.164 \| good
2025-09-11T21:00:00.000Z	33 \| good	5.992 \| good	26.457 \| good	35.126 \| good	1.057 \| good	3.627 \| good	0.167 \| good
2025-09-11T22:00:00.000Z	44 \| good	8.123 \| good	35.746 \| good	26.67 \| good	1.182 \| good	10.868 \| good	0.227 \| good
2025-09-11T23:00:00.000Z	49 \| good	9.217 \| good	40.638 \| good	17.695 \| good	1.306 \| good	18.109 \| good	0.287 \| good
2025-09-12T00:00:00.000Z	52 \| moderate	10.113 \| good	44.931 \| good	16.824 \| good	1.431 \| good	25.351 \| good	0.347 \| good
2025-09-12T01:00:00.000Z	58 \| moderate	12.984 \| fine	58.052 \| fine	17.138 \| good	1.407 \| good	24.65 \| good	0.348 \| good
2025-09-12T02:00:00.000Z	62 \| moderate	15.022 \| fine	67.454 \| fine	10.842 \| good	1.383 \| good	23.95 \| good	0.349 \| good
2025-09-12T03:00:00.000Z	64 \| moderate	15.817 \| fine	70.426 \| fine	6.246 \| good	1.359 \| good	23.249 \| good	0.35 \| good
2025-09-12T04:00:00.000Z	56 \| moderate	12.397 \| fine	55.837 \| fine	13.041 \| good	1.104 \| good	16.909 \| good	0.295 \| good
2025-09-12T05:00:00.000Z	54 \| moderate	11.247 \| good	50.041 \| good	18.798 \| good	0.849 \| good	10.569 \| good	0.239 \| good
2025-09-12T06:00:00.000Z	52 \| moderate	9.657 \| good	43.104 \| good	19.933 \| good	0.594 \| good	4.229 \| good	0.184 \| good
2025-09-12T07:00:00.000Z	49 \| good	9.443 \| good	42.096 \| good	18.784 \| good	0.623 \| good	3.927 \| good	0.178 \| good
2025-09-12T08:00:00.000Z	54 \| moderate	10.863 \| good	48.084 \| good	16.269 \| good	0.653 \| good	3.624 \| good	0.171 \| good
2025-09-12T09:00:00.000Z	27 \| good	5.477 \| good	23.228 \| good	9.695 \| good	0.682 \| good	3.321 \| good	0.165 \| good
2025-09-12T10:00:00.000Z	38 \| good	6.65 \| good	29.749 \| good	4.762 \| good	0.744 \| good	4.314 \| good	0.176 \| good
2025-09-12T11:00:00.000Z	33 \| good	6.327 \| good	28.49 \| good	7.21 \| good	0.805 \| good	5.307 \| good	0.186 \| good
2025-09-12T12:00:00.000Z	27 \| good	5.457 \| good	23.294 \| good	13.947 \| good	0.867 \| good	6.3 \| good	0.197 \| good
2025-09-12T13:00:00.000Z	27 \| good	4.529 \| good	19.267 \| good	18.734 \| good	0.772 \| good	5.05 \| good	0.183 \| good
2025-09-12T14:00:00.000Z	22 \| good	3.839 \| good	16.935 \| good	20.279 \| good	0.678 \| good	3.799 \| good	0.17 \| good
2025-09-12T15:00:00.000Z	23 \| good	4.479 \| good	19.163 \| good	24.783 \| good	0.584 \| good	2.548 \| good	0.156 \| good
2025-09-12T16:00:00.000Z	33 \| good	6.262 \| good	27.865 \| good	29.398 \| good	0.569 \| good	2.334 \| good	0.154 \| good
2025-09-12T17:00:00.000Z	38 \| good	6.503 \| good	29.031 \| good	35.415 \| good	0.554 \| good	2.119 \| good	0.153 \| good
2025-09-12T18:00:00.000Z	38 \| good	6.852 \| good	30.104 \| good	39.817 \| good	0.54 \| good	1.904 \| good	0.151 \| good
2025-09-12T19:00:00.000Z	38 \| good	6.574 \| good	29.037 \| good	37.632 \| good	0.59 \| good	2.376 \| good	0.153 \| good
2025-09-12T20:00:00.000Z	38 \| good	6.527 \| good	29.103 \| good	29.833 \| good	0.641 \| good	2.847 \| good	0.156 \| good
2025-09-12T21:00:00.000Z	33 \| good	5.981 \| good	25.929 \| good	24.586 \| good	0.691 \| good	3.319 \| good	0.158 \| good
2025-09-12T22:00:00.000Z	27 \| good	5.096 \| good	21.848 \| good	17.08 \| good	0.812 \| good	7.84 \| good	0.187 \| good
2025-09-12T23:00:00.000Z	27 \| good	5.05 \| good	21.581 \| good	10.438 \| good	0.932 \| good	12.36 \| good	0.216 \| good
2025-09-13T00:00:00.000Z	27 \| good	4.616 \| good	20.297 \| good	8.955 \| good	1.052 \| good	16.881 \| good	0.245 \| good
2025-09-13T01:00:00.000Z	27 \| good	4.964 \| good	21.495 \| good	10.298 \| good	1.114 \| good	18.74 \| good	0.255 \| good
2025-09-13T02:00:00.000Z	22 \| good	3.724 \| good	16.118 \| good	11.308 \| good	1.176 \| good	20.599 \| good	0.265 \| good
2025-09-13T03:00:00.000Z	22 \| good	4.178 \| good	18.131 \| good	9.992 \| good	1.238 \| good	22.459 \| good	0.276 \| good
2025-09-13T04:00:00.000Z	33 \| good	5.615 \| good	24.198 \| good	10.248 \| good	1.257 \| good	22.84 \| good	0.283 \| good
2025-09-13T05:00:00.000Z	33 \| good	5.888 \| good	25.335 \| good	10.234 \| good	1.277 \| good	23.222 \| good	0.291 \| good
2025-09-13T06:00:00.000Z	33 \| good	5.511 \| good	23.967 \| good	10.5 \| good	1.297 \| good	23.604 \| good	0.299 \| good
2025-09-13T07:00:00.000Z	27 \| good	4.713 \| good	20.659 \| good	12.02 \| good	1.363 \| good	21.938 \| good	0.285 \| good
2025-09-13T08:00:00.000Z	22 \| good	4.314 \| good	18.928 \| good	11.786 \| good	1.429 \| good	20.272 \| good	0.272 \| good
2025-09-13T09:00:00.000Z	22 \| good	4.27 \| good	18.795 \| good	10.468 \| good	1.495 \| good	18.606 \| good	0.258 \| good
2025-09-13T10:00:00.000Z	22 \| good	4.5 \| good	19.23 \| good	10.199 \| good	1.582 \| good	17.613 \| good	0.278 \| good
2025-09-13T11:00:00.000Z	27 \| good	4.753 \| good	20.586 \| good	10.273 \| good	1.67 \| good	16.621 \| good	0.298 \| good
2025-09-13T12:00:00.000Z	22 \| good	3.974 \| good	17.747 \| good	14.712 \| good	1.757 \| good	15.629 \| good	0.318 \| good
2025-09-13T13:00:00.000Z	22 \| good	4.306 \| good	18.816 \| good	20.372 \| good	1.682 \| good	13.028 \| good	0.272 \| good
2025-09-13T14:00:00.000Z	33 \| good	5.6 \| good	23.997 \| good	27.243 \| good	1.607 \| good	10.428 \| good	0.225 \| good
2025-09-13T15:00:00.000Z	44 \| good	8.041 \| good	35.024 \| good	34.151 \| good	1.532 \| good	7.827 \| good	0.179 \| good

Live air quality index in Waltham, Massachusetts today

Major air pollutants in Waltham, Massachusetts

Particulate Matter2.5 (PM2.5)

Particulate Matter10 (PM10)

Ozone (O3)

Sulfur Dioxide (SO2)

Nitrogen Dioxide (NO2)

Carbon Monoxide (CO)

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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 Waltham, Massachusetts at the moment?

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What is the ozone (O₃) level in Waltham, Massachusetts at the moment?

What is the nitrogen dioxide (NO₂) level in Waltham, Massachusetts at the moment?