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

Currently, Waltham, Massachusetts has a sulfur dioxide (SO2) concentration of 0.353 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 22.106 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 6.595 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)

25.42 μg/m³

12.1

35.5

55.5

250.5

500.5+

Particulate Matter₁₀ (PM₁₀)

61.36 μg/m³

155

255

425

605+

Ozone (O₃)

23.07 ppb

201

201+

Sulfur Dioxide (SO₂)

0.32 ppb

186

605

1005+

Nitrogen Dioxide (NO₂)

4.26 ppb

101

361

1250

2050+

Carbon Monoxide (CO)

0.27 ppm

4.5

9.5

12.5

230.5

50.5+

Pollen Level

Low

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
2025-07-30T05:00:00.000Z	52 \| moderate	10.32 \| good	42.289 \| good	27.661 \| good	0.434 \| good	15.405 \| good	0.34 \| good
2025-07-30T06:00:00.000Z	57 \| moderate	8.668 \| good	67.165 \| fine	34.337 \| good	0.348 \| good	20.707 \| good	0.281 \| good
2025-07-30T07:00:00.000Z	54 \| moderate	7.989 \| good	61.351 \| fine	24.353 \| good	0.503 \| good	15.735 \| good	0.334 \| good
2025-07-30T08:00:00.000Z	56 \| moderate	10.173 \| good	65.969 \| fine	25.843 \| good	0.553 \| good	14.999 \| good	0.323 \| good
2025-07-30T09:00:00.000Z	58 \| moderate	9.618 \| good	69.72 \| fine	21.996 \| good	0.508 \| good	10.067 \| good	0.222 \| good
2025-07-30T10:00:00.000Z	49 \| good	8.887 \| good	38.405 \| good	21.167 \| good	0.409 \| good	10.818 \| good	0.222 \| good
2025-07-30T11:00:00.000Z	52 \| moderate	9.939 \| good	19.826 \| good	19.095 \| good	0.406 \| good	10.346 \| good	0.244 \| good
2025-07-30T12:00:00.000Z	54 \| moderate	11.026 \| good	51.175 \| good	20.667 \| good	0.415 \| good	10.474 \| good	0.34 \| good
2025-07-30T13:00:00.000Z	52 \| moderate	10.4 \| good	47.645 \| good	28.145 \| good	0.44 \| good	9.408 \| good	0.31 \| good
2025-07-30T14:00:00.000Z	82 \| moderate	9.197 \| good	117.34 \| fine	30.196 \| good	0.542 \| good	9.174 \| good	0.266 \| good
2025-07-30T15:00:00.000Z	54 \| moderate	10.256 \| good	62.232 \| fine	29.863 \| good	0.453 \| good	7.783 \| good	0.256 \| good
2025-07-30T16:00:00.000Z	49 \| good	8.783 \| good	40.113 \| good	39.456 \| good	0.433 \| good	7.852 \| good	0.233 \| good
2025-07-30T17:00:00.000Z	52 \| moderate	9.666 \| good	39.222 \| good	40.629 \| good	0.607 \| good	10.523 \| good	0.266 \| good
2025-07-30T18:00:00.000Z	49 \| good	9.408 \| good	33.794 \| good	44.226 \| good	0.626 \| good	8.777 \| good	0.251 \| good
2025-07-30T19:00:00.000Z	49 \| good	9.016 \| good	30.468 \| good	42.717 \| good	0.592 \| good	8.171 \| good	0.256 \| good
2025-07-30T20:00:00.000Z	49 \| good	8.948 \| good	40.725 \| good	47.073 \| good	0.506 \| good	7.513 \| good	0.256 \| good
2025-07-30T21:00:00.000Z	52 \| moderate	9.922 \| good	38.12 \| good	44.751 \| good	0.547 \| good	8.473 \| good	0.278 \| good
2025-07-30T22:00:00.000Z	52 \| moderate	10.424 \| good	45.71 \| good	41.035 \| good	0.476 \| good	9.068 \| good	0.311 \| good
2025-07-30T23:00:00.000Z	52 \| moderate	9.579 \| good	38.151 \| good	39.461 \| good	0.66 \| good	13.112 \| good	0.245 \| good
2025-07-31T00:00:00.000Z	49 \| good	9.073 \| good	31.034 \| good	48.164 \| good	0.419 \| good	8.079 \| good	0.245 \| good
2025-07-31T01:00:00.000Z	54 \| moderate	10.882 \| good	52.956 \| good	46.388 \| good	0.446 \| good	10.136 \| good	0.312 \| good
2025-07-31T02:00:00.000Z	49 \| good	9.066 \| good	40.842 \| good	37.099 \| good	0.468 \| good	9.004 \| good	0.278 \| good
2025-07-31T03:00:00.000Z	52 \| moderate	9.705 \| good	34.431 \| good	33.767 \| good	0.429 \| good	7.671 \| good	0.245 \| good
2025-07-31T04:00:00.000Z	52 \| moderate	9.969 \| good	47.025 \| good	34.981 \| good	0.41 \| good	7.607 \| good	0.275 \| good
2025-07-31T05:00:00.000Z	52 \| moderate	9.64 \| good	46.796 \| good	39.396 \| good	0.408 \| good	11.025 \| good	0.3 \| good
2025-07-31T06:00:00.000Z	55 \| moderate	10.197 \| good	62.872 \| fine	32.366 \| good	0.833 \| good	11.721 \| good	0.318 \| good
2025-07-31T07:00:00.000Z	71 \| moderate	19.634 \| fine	57.119 \| fine	17.239 \| good	0.365 \| good	12.15 \| good	0.221 \| good
2025-07-31T08:00:00.000Z	49 \| good	8.986 \| good	37.631 \| good	20.835 \| good	0.434 \| good	12.805 \| good	0.221 \| good
2025-07-31T09:00:00.000Z	54 \| moderate	10.507 \| good	52.745 \| good	25.673 \| good	0.525 \| good	7.431 \| good	0.177 \| good
2025-07-31T10:00:00.000Z	56 \| moderate	12.152 \| fine	52.715 \| good	28.783 \| good	0.415 \| good	5.29 \| good	0.177 \| good
2025-07-31T11:00:00.000Z	52 \| moderate	10.201 \| good	49.811 \| good	25.608 \| good	0.383 \| good	5.01 \| good	0.266 \| good
2025-07-31T12:00:00.000Z	56 \| moderate	11.659 \| good	55.445 \| fine	26.809 \| good	0.674 \| good	6.625 \| good	0.277 \| good
2025-07-31T13:00:00.000Z	62 \| moderate	14.607 \| fine	52.599 \| good	26.374 \| good	0.401 \| good	7.708 \| good	0.311 \| good
2025-07-31T14:00:00.000Z	66 \| moderate	16.518 \| fine	68.666 \| fine	26.577 \| good	0.336 \| good	7.044 \| good	0.322 \| good
2025-07-31T15:00:00.000Z	69 \| moderate	18.947 \| fine	84.502 \| fine	27.641 \| good	0.325 \| good	7.309 \| good	0.355 \| good
2025-07-31T16:00:00.000Z	71 \| moderate	19.879 \| fine	79.449 \| fine	27.331 \| good	0.388 \| good	5.758 \| good	0.355 \| good
2025-07-31T17:00:00.000Z	81 \| moderate	25.149 \| fine	105.697 \| fine	24.229 \| good	0.354 \| good	6.512 \| good	0.322 \| good
2025-07-31T18:00:00.000Z	88 \| moderate	29.248 \| fine	113.055 \| fine	22.265 \| good	0.319 \| good	5.209 \| good	0.322 \| good
2025-07-31T19:00:00.000Z	88 \| moderate	28.667 \| fine	100.961 \| fine	24.811 \| good	0.357 \| good	4.566 \| good	0.355 \| good
2025-07-31T20:00:00.000Z	94 \| moderate	31.752 \| fine	93.369 \| fine	27.899 \| good	0.398 \| good	3.95 \| good	0.322 \| good
2025-07-31T21:00:00.000Z	94 \| moderate	31.639 \| fine	108.397 \| fine	23.292 \| good	0.367 \| good	4.927 \| good	0.311 \| good
2025-07-31T22:00:00.000Z	92 \| moderate	30.633 \| fine	59.093 \| fine	23.715 \| good	0.335 \| good	5.895 \| good	0.311 \| good
2025-07-31T23:00:00.000Z	60 \| moderate	14.086 \| fine	62.431 \| fine	20.576 \| good	0.812 \| good	6.426 \| good	0.289 \| good
2025-08-01T00:00:00.000Z	88 \| moderate	29.089 \| fine	35.833 \| good	24.857 \| good	0.345 \| good	7.309 \| good	0.311 \| good
2025-08-01T01:00:00.000Z	79 \| moderate	24.439 \| fine	53.798 \| good	20.991 \| good	0.339 \| good	5.371 \| good	0.3 \| good
2025-08-01T02:00:00.000Z	88 \| moderate	28.836 \| fine	124.458 \| fine	21.051 \| good	0.305 \| good	4.513 \| good	0.266 \| good
2025-08-01T03:00:00.000Z	84 \| moderate	26.995 \| fine	118.407 \| fine	25.201 \| good	0.315 \| good	4.637 \| good	0.266 \| good
2025-08-01T04:00:00.000Z	81 \| moderate	25.42 \| fine	61.356 \| fine	23.075 \| good	0.315 \| good	4.258 \| good	0.266 \| good
2025-07-31T18:00:00.000Z	62 \| moderate	14.524 \| fine	64.904 \| fine	16.571 \| good	0.79 \| good	3.386 \| good	0.259 \| good
2025-07-31T19:00:00.000Z	62 \| moderate	15.364 \| fine	68.653 \| fine	15.745 \| good	0.871 \| good	4.129 \| good	0.263 \| good
2025-07-31T20:00:00.000Z	62 \| moderate	15.22 \| fine	68.045 \| fine	18.188 \| good	0.951 \| good	4.872 \| good	0.266 \| good
2025-07-31T21:00:00.000Z	60 \| moderate	13.566 \| fine	61.104 \| fine	17.673 \| good	1.031 \| good	5.616 \| good	0.27 \| good
2025-07-31T22:00:00.000Z	56 \| moderate	11.909 \| good	53.088 \| good	18.613 \| good	1.005 \| good	6.505 \| good	0.273 \| good
2025-07-31T23:00:00.000Z	56 \| moderate	12.458 \| fine	56.511 \| fine	18.715 \| good	0.979 \| good	7.395 \| good	0.276 \| good
2025-08-01T00:00:00.000Z	58 \| moderate	12.671 \| fine	57.386 \| fine	21.281 \| good	0.953 \| good	8.284 \| good	0.28 \| good
2025-08-01T01:00:00.000Z	60 \| moderate	13.875 \| fine	62.192 \| fine	18.959 \| good	0.908 \| good	7.636 \| good	0.273 \| good
2025-08-01T02:00:00.000Z	64 \| moderate	16.388 \| fine	72.757 \| fine	18.127 \| good	0.863 \| good	6.988 \| good	0.267 \| good
2025-08-01T03:00:00.000Z	66 \| moderate	16.676 \| fine	74.339 \| fine	19.998 \| good	0.818 \| good	6.34 \| good	0.26 \| good
2025-08-01T04:00:00.000Z	66 \| moderate	17.271 \| fine	76.476 \| fine	22.466 \| good	0.805 \| good	5.753 \| good	0.254 \| good
2025-08-01T05:00:00.000Z	66 \| moderate	17.119 \| fine	75.864 \| fine	23.599 \| good	0.793 \| good	5.167 \| good	0.247 \| good
2025-08-01T06:00:00.000Z	64 \| moderate	15.971 \| fine	71.29 \| fine	23.311 \| good	0.78 \| good	4.58 \| good	0.241 \| good
2025-08-01T07:00:00.000Z	62 \| moderate	14.688 \| fine	65.357 \| fine	24.298 \| good	0.743 \| good	4.045 \| good	0.234 \| good
2025-08-01T08:00:00.000Z	58 \| moderate	13.095 \| fine	58.737 \| fine	23.857 \| good	0.706 \| good	3.509 \| good	0.227 \| good
2025-08-01T09:00:00.000Z	49 \| good	8.74 \| good	38.457 \| good	23.397 \| good	0.67 \| good	2.973 \| good	0.22 \| good
2025-08-01T10:00:00.000Z	49 \| good	9.205 \| good	40.982 \| good	21.51 \| good	0.661 \| good	3.699 \| good	0.221 \| good
2025-08-01T11:00:00.000Z	44 \| good	8.289 \| good	36.364 \| good	19.349 \| good	0.653 \| good	4.425 \| good	0.221 \| good
2025-08-01T12:00:00.000Z	44 \| good	8.466 \| good	37.252 \| good	17.229 \| good	0.644 \| good	5.151 \| good	0.222 \| good
2025-08-01T13:00:00.000Z	52 \| moderate	9.521 \| good	42.496 \| good	17.613 \| good	0.627 \| good	4.515 \| good	0.209 \| good
2025-08-01T14:00:00.000Z	49 \| good	9.25 \| good	41.218 \| good	18.828 \| good	0.61 \| good	3.88 \| good	0.197 \| good
2025-08-01T15:00:00.000Z	52 \| moderate	9.796 \| good	43.645 \| good	19.177 \| good	0.593 \| good	3.245 \| good	0.184 \| good
2025-08-01T16:00:00.000Z	49 \| good	9.322 \| good	41.496 \| good	23.066 \| good	0.58 \| good	2.786 \| good	0.182 \| good
2025-08-01T17:00:00.000Z	38 \| good	6.691 \| good	29.583 \| good	28.236 \| good	0.566 \| good	2.327 \| good	0.179 \| good
2025-08-01T18:00:00.000Z	33 \| good	5.77 \| good	24.859 \| good	28.315 \| good	0.553 \| good	1.867 \| good	0.177 \| good
2025-08-01T19:00:00.000Z	33 \| good	5.93 \| good	26.093 \| good	27.454 \| good	0.591 \| good	2.009 \| good	0.176 \| good
2025-08-01T20:00:00.000Z	33 \| good	6.205 \| good	27.44 \| good	28.077 \| good	0.628 \| good	2.151 \| good	0.176 \| good
2025-08-01T21:00:00.000Z	33 \| good	5.873 \| good	25.481 \| good	27.313 \| good	0.665 \| good	2.293 \| good	0.176 \| good
2025-08-01T22:00:00.000Z	33 \| good	6.476 \| good	28.747 \| good	26.037 \| good	0.774 \| good	4.54 \| good	0.189 \| good
2025-08-01T23:00:00.000Z	38 \| good	6.939 \| good	30.789 \| good	23.222 \| good	0.884 \| good	6.786 \| good	0.202 \| good
2025-08-02T00:00:00.000Z	49 \| good	8.58 \| good	37.59 \| good	22.114 \| good	0.993 \| good	9.033 \| good	0.216 \| good
2025-08-02T01:00:00.000Z	49 \| good	9.075 \| good	39.884 \| good	19.487 \| good	1.111 \| good	10.668 \| good	0.228 \| good
2025-08-02T02:00:00.000Z	49 \| good	9.378 \| good	41.768 \| good	19.513 \| good	1.229 \| good	12.304 \| good	0.24 \| good
2025-08-02T03:00:00.000Z	52 \| moderate	10.442 \| good	46.136 \| good	19.847 \| good	1.347 \| good	13.94 \| good	0.252 \| good
2025-08-02T04:00:00.000Z	54 \| moderate	10.565 \| good	46.884 \| good	21.104 \| good	1.324 \| good	12.269 \| good	0.24 \| good
2025-08-02T05:00:00.000Z	54 \| moderate	11.398 \| good	50.259 \| good	21.47 \| good	1.301 \| good	10.598 \| good	0.228 \| good
2025-08-02T06:00:00.000Z	54 \| moderate	10.616 \| good	47.13 \| good	19.878 \| good	1.278 \| good	8.927 \| good	0.216 \| good
2025-08-02T07:00:00.000Z	52 \| moderate	9.536 \| good	42.675 \| good	19.625 \| good	1.178 \| good	7.761 \| good	0.209 \| good
2025-08-02T08:00:00.000Z	49 \| good	8.668 \| good	37.851 \| good	17.569 \| good	1.078 \| good	6.594 \| good	0.202 \| good
2025-08-02T09:00:00.000Z	38 \| good	6.812 \| good	30.184 \| good	15.941 \| good	0.978 \| good	5.428 \| good	0.194 \| good
2025-08-02T10:00:00.000Z	44 \| good	7.703 \| good	34.002 \| good	15.665 \| good	0.95 \| good	5.358 \| good	0.2 \| good
2025-08-02T11:00:00.000Z	52 \| moderate	9.699 \| good	43.331 \| good	16.914 \| good	0.922 \| good	5.289 \| good	0.205 \| good
2025-08-02T12:00:00.000Z	52 \| moderate	10.423 \| good	46.246 \| good	21.946 \| good	0.894 \| good	5.219 \| good	0.21 \| good
2025-08-02T13:00:00.000Z	52 \| moderate	10.153 \| good	44.967 \| good	27.288 \| good	0.873 \| good	4.323 \| good	0.2 \| good
2025-08-02T14:00:00.000Z	44 \| good	8.255 \| good	36.369 \| good	33.282 \| good	0.852 \| good	3.426 \| good	0.19 \| good
2025-08-02T15:00:00.000Z	44 \| good	7.999 \| good	35.127 \| good	36.329 \| good	0.832 \| good	2.53 \| good	0.18 \| good
2025-08-02T16:00:00.000Z	44 \| good	7.571 \| good	33.478 \| good	36.108 \| good	0.796 \| good	2.331 \| good	0.178 \| good
2025-08-02T17:00:00.000Z	44 \| good	8.43 \| good	37.055 \| good	32.39 \| good	0.761 \| good	2.131 \| good	0.176 \| good

Waltham

Get reliable air quality data to drive your business

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

0.35ppm

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 04:00:00 on 2025-07-31.

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 10:00:00 on 2025-07-31.

What is the AQI in Waltham, Massachusetts right now?

As of now, the AQI in Waltham, Massachusetts is 81, indicating Moderate 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 25.204 μg/m³.

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

The PM₁₀ concentration in Waltham, Massachusetts is 105.798 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 0.322 ppm.

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

Currently, Waltham, Massachusetts has a sulfur dioxide (SO₂) concentration of 0.353 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 22.106 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 6.595 ppb.

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Time	AQI	PM_2.5	PM₁₀	O₃	SO₂	NO₂	CO
2025-07-30T05:00:00.000Z	52 \| moderate	10.32 \| good	42.289 \| good	27.661 \| good	0.434 \| good	15.405 \| good	0.34 \| good
2025-07-30T06:00:00.000Z	57 \| moderate	8.668 \| good	67.165 \| fine	34.337 \| good	0.348 \| good	20.707 \| good	0.281 \| good
2025-07-30T07:00:00.000Z	54 \| moderate	7.989 \| good	61.351 \| fine	24.353 \| good	0.503 \| good	15.735 \| good	0.334 \| good
2025-07-30T08:00:00.000Z	56 \| moderate	10.173 \| good	65.969 \| fine	25.843 \| good	0.553 \| good	14.999 \| good	0.323 \| good
2025-07-30T09:00:00.000Z	58 \| moderate	9.618 \| good	69.72 \| fine	21.996 \| good	0.508 \| good	10.067 \| good	0.222 \| good
2025-07-30T10:00:00.000Z	49 \| good	8.887 \| good	38.405 \| good	21.167 \| good	0.409 \| good	10.818 \| good	0.222 \| good
2025-07-30T11:00:00.000Z	52 \| moderate	9.939 \| good	19.826 \| good	19.095 \| good	0.406 \| good	10.346 \| good	0.244 \| good
2025-07-30T12:00:00.000Z	54 \| moderate	11.026 \| good	51.175 \| good	20.667 \| good	0.415 \| good	10.474 \| good	0.34 \| good
2025-07-30T13:00:00.000Z	52 \| moderate	10.4 \| good	47.645 \| good	28.145 \| good	0.44 \| good	9.408 \| good	0.31 \| good
2025-07-30T14:00:00.000Z	82 \| moderate	9.197 \| good	117.34 \| fine	30.196 \| good	0.542 \| good	9.174 \| good	0.266 \| good
2025-07-30T15:00:00.000Z	54 \| moderate	10.256 \| good	62.232 \| fine	29.863 \| good	0.453 \| good	7.783 \| good	0.256 \| good
2025-07-30T16:00:00.000Z	49 \| good	8.783 \| good	40.113 \| good	39.456 \| good	0.433 \| good	7.852 \| good	0.233 \| good
2025-07-30T17:00:00.000Z	52 \| moderate	9.666 \| good	39.222 \| good	40.629 \| good	0.607 \| good	10.523 \| good	0.266 \| good
2025-07-30T18:00:00.000Z	49 \| good	9.408 \| good	33.794 \| good	44.226 \| good	0.626 \| good	8.777 \| good	0.251 \| good
2025-07-30T19:00:00.000Z	49 \| good	9.016 \| good	30.468 \| good	42.717 \| good	0.592 \| good	8.171 \| good	0.256 \| good
2025-07-30T20:00:00.000Z	49 \| good	8.948 \| good	40.725 \| good	47.073 \| good	0.506 \| good	7.513 \| good	0.256 \| good
2025-07-30T21:00:00.000Z	52 \| moderate	9.922 \| good	38.12 \| good	44.751 \| good	0.547 \| good	8.473 \| good	0.278 \| good
2025-07-30T22:00:00.000Z	52 \| moderate	10.424 \| good	45.71 \| good	41.035 \| good	0.476 \| good	9.068 \| good	0.311 \| good
2025-07-30T23:00:00.000Z	52 \| moderate	9.579 \| good	38.151 \| good	39.461 \| good	0.66 \| good	13.112 \| good	0.245 \| good
2025-07-31T00:00:00.000Z	49 \| good	9.073 \| good	31.034 \| good	48.164 \| good	0.419 \| good	8.079 \| good	0.245 \| good
2025-07-31T01:00:00.000Z	54 \| moderate	10.882 \| good	52.956 \| good	46.388 \| good	0.446 \| good	10.136 \| good	0.312 \| good
2025-07-31T02:00:00.000Z	49 \| good	9.066 \| good	40.842 \| good	37.099 \| good	0.468 \| good	9.004 \| good	0.278 \| good
2025-07-31T03:00:00.000Z	52 \| moderate	9.705 \| good	34.431 \| good	33.767 \| good	0.429 \| good	7.671 \| good	0.245 \| good
2025-07-31T04:00:00.000Z	52 \| moderate	9.969 \| good	47.025 \| good	34.981 \| good	0.41 \| good	7.607 \| good	0.275 \| good
2025-07-31T05:00:00.000Z	52 \| moderate	9.64 \| good	46.796 \| good	39.396 \| good	0.408 \| good	11.025 \| good	0.3 \| good
2025-07-31T06:00:00.000Z	55 \| moderate	10.197 \| good	62.872 \| fine	32.366 \| good	0.833 \| good	11.721 \| good	0.318 \| good
2025-07-31T07:00:00.000Z	71 \| moderate	19.634 \| fine	57.119 \| fine	17.239 \| good	0.365 \| good	12.15 \| good	0.221 \| good
2025-07-31T08:00:00.000Z	49 \| good	8.986 \| good	37.631 \| good	20.835 \| good	0.434 \| good	12.805 \| good	0.221 \| good
2025-07-31T09:00:00.000Z	54 \| moderate	10.507 \| good	52.745 \| good	25.673 \| good	0.525 \| good	7.431 \| good	0.177 \| good
2025-07-31T10:00:00.000Z	56 \| moderate	12.152 \| fine	52.715 \| good	28.783 \| good	0.415 \| good	5.29 \| good	0.177 \| good
2025-07-31T11:00:00.000Z	52 \| moderate	10.201 \| good	49.811 \| good	25.608 \| good	0.383 \| good	5.01 \| good	0.266 \| good
2025-07-31T12:00:00.000Z	56 \| moderate	11.659 \| good	55.445 \| fine	26.809 \| good	0.674 \| good	6.625 \| good	0.277 \| good
2025-07-31T13:00:00.000Z	62 \| moderate	14.607 \| fine	52.599 \| good	26.374 \| good	0.401 \| good	7.708 \| good	0.311 \| good
2025-07-31T14:00:00.000Z	66 \| moderate	16.518 \| fine	68.666 \| fine	26.577 \| good	0.336 \| good	7.044 \| good	0.322 \| good
2025-07-31T15:00:00.000Z	69 \| moderate	18.947 \| fine	84.502 \| fine	27.641 \| good	0.325 \| good	7.309 \| good	0.355 \| good
2025-07-31T16:00:00.000Z	71 \| moderate	19.879 \| fine	79.449 \| fine	27.331 \| good	0.388 \| good	5.758 \| good	0.355 \| good
2025-07-31T17:00:00.000Z	81 \| moderate	25.149 \| fine	105.697 \| fine	24.229 \| good	0.354 \| good	6.512 \| good	0.322 \| good
2025-07-31T18:00:00.000Z	88 \| moderate	29.248 \| fine	113.055 \| fine	22.265 \| good	0.319 \| good	5.209 \| good	0.322 \| good
2025-07-31T19:00:00.000Z	88 \| moderate	28.667 \| fine	100.961 \| fine	24.811 \| good	0.357 \| good	4.566 \| good	0.355 \| good
2025-07-31T20:00:00.000Z	94 \| moderate	31.752 \| fine	93.369 \| fine	27.899 \| good	0.398 \| good	3.95 \| good	0.322 \| good
2025-07-31T21:00:00.000Z	94 \| moderate	31.639 \| fine	108.397 \| fine	23.292 \| good	0.367 \| good	4.927 \| good	0.311 \| good
2025-07-31T22:00:00.000Z	92 \| moderate	30.633 \| fine	59.093 \| fine	23.715 \| good	0.335 \| good	5.895 \| good	0.311 \| good
2025-07-31T23:00:00.000Z	60 \| moderate	14.086 \| fine	62.431 \| fine	20.576 \| good	0.812 \| good	6.426 \| good	0.289 \| good
2025-08-01T00:00:00.000Z	88 \| moderate	29.089 \| fine	35.833 \| good	24.857 \| good	0.345 \| good	7.309 \| good	0.311 \| good
2025-08-01T01:00:00.000Z	79 \| moderate	24.439 \| fine	53.798 \| good	20.991 \| good	0.339 \| good	5.371 \| good	0.3 \| good
2025-08-01T02:00:00.000Z	88 \| moderate	28.836 \| fine	124.458 \| fine	21.051 \| good	0.305 \| good	4.513 \| good	0.266 \| good
2025-08-01T03:00:00.000Z	84 \| moderate	26.995 \| fine	118.407 \| fine	25.201 \| good	0.315 \| good	4.637 \| good	0.266 \| good
2025-08-01T04:00:00.000Z	81 \| moderate	25.42 \| fine	61.356 \| fine	23.075 \| good	0.315 \| good	4.258 \| good	0.266 \| good
2025-07-31T18:00:00.000Z	62 \| moderate	14.524 \| fine	64.904 \| fine	16.571 \| good	0.79 \| good	3.386 \| good	0.259 \| good
2025-07-31T19:00:00.000Z	62 \| moderate	15.364 \| fine	68.653 \| fine	15.745 \| good	0.871 \| good	4.129 \| good	0.263 \| good
2025-07-31T20:00:00.000Z	62 \| moderate	15.22 \| fine	68.045 \| fine	18.188 \| good	0.951 \| good	4.872 \| good	0.266 \| good
2025-07-31T21:00:00.000Z	60 \| moderate	13.566 \| fine	61.104 \| fine	17.673 \| good	1.031 \| good	5.616 \| good	0.27 \| good
2025-07-31T22:00:00.000Z	56 \| moderate	11.909 \| good	53.088 \| good	18.613 \| good	1.005 \| good	6.505 \| good	0.273 \| good
2025-07-31T23:00:00.000Z	56 \| moderate	12.458 \| fine	56.511 \| fine	18.715 \| good	0.979 \| good	7.395 \| good	0.276 \| good
2025-08-01T00:00:00.000Z	58 \| moderate	12.671 \| fine	57.386 \| fine	21.281 \| good	0.953 \| good	8.284 \| good	0.28 \| good
2025-08-01T01:00:00.000Z	60 \| moderate	13.875 \| fine	62.192 \| fine	18.959 \| good	0.908 \| good	7.636 \| good	0.273 \| good
2025-08-01T02:00:00.000Z	64 \| moderate	16.388 \| fine	72.757 \| fine	18.127 \| good	0.863 \| good	6.988 \| good	0.267 \| good
2025-08-01T03:00:00.000Z	66 \| moderate	16.676 \| fine	74.339 \| fine	19.998 \| good	0.818 \| good	6.34 \| good	0.26 \| good
2025-08-01T04:00:00.000Z	66 \| moderate	17.271 \| fine	76.476 \| fine	22.466 \| good	0.805 \| good	5.753 \| good	0.254 \| good
2025-08-01T05:00:00.000Z	66 \| moderate	17.119 \| fine	75.864 \| fine	23.599 \| good	0.793 \| good	5.167 \| good	0.247 \| good
2025-08-01T06:00:00.000Z	64 \| moderate	15.971 \| fine	71.29 \| fine	23.311 \| good	0.78 \| good	4.58 \| good	0.241 \| good
2025-08-01T07:00:00.000Z	62 \| moderate	14.688 \| fine	65.357 \| fine	24.298 \| good	0.743 \| good	4.045 \| good	0.234 \| good
2025-08-01T08:00:00.000Z	58 \| moderate	13.095 \| fine	58.737 \| fine	23.857 \| good	0.706 \| good	3.509 \| good	0.227 \| good
2025-08-01T09:00:00.000Z	49 \| good	8.74 \| good	38.457 \| good	23.397 \| good	0.67 \| good	2.973 \| good	0.22 \| good
2025-08-01T10:00:00.000Z	49 \| good	9.205 \| good	40.982 \| good	21.51 \| good	0.661 \| good	3.699 \| good	0.221 \| good
2025-08-01T11:00:00.000Z	44 \| good	8.289 \| good	36.364 \| good	19.349 \| good	0.653 \| good	4.425 \| good	0.221 \| good
2025-08-01T12:00:00.000Z	44 \| good	8.466 \| good	37.252 \| good	17.229 \| good	0.644 \| good	5.151 \| good	0.222 \| good
2025-08-01T13:00:00.000Z	52 \| moderate	9.521 \| good	42.496 \| good	17.613 \| good	0.627 \| good	4.515 \| good	0.209 \| good
2025-08-01T14:00:00.000Z	49 \| good	9.25 \| good	41.218 \| good	18.828 \| good	0.61 \| good	3.88 \| good	0.197 \| good
2025-08-01T15:00:00.000Z	52 \| moderate	9.796 \| good	43.645 \| good	19.177 \| good	0.593 \| good	3.245 \| good	0.184 \| good
2025-08-01T16:00:00.000Z	49 \| good	9.322 \| good	41.496 \| good	23.066 \| good	0.58 \| good	2.786 \| good	0.182 \| good
2025-08-01T17:00:00.000Z	38 \| good	6.691 \| good	29.583 \| good	28.236 \| good	0.566 \| good	2.327 \| good	0.179 \| good
2025-08-01T18:00:00.000Z	33 \| good	5.77 \| good	24.859 \| good	28.315 \| good	0.553 \| good	1.867 \| good	0.177 \| good
2025-08-01T19:00:00.000Z	33 \| good	5.93 \| good	26.093 \| good	27.454 \| good	0.591 \| good	2.009 \| good	0.176 \| good
2025-08-01T20:00:00.000Z	33 \| good	6.205 \| good	27.44 \| good	28.077 \| good	0.628 \| good	2.151 \| good	0.176 \| good
2025-08-01T21:00:00.000Z	33 \| good	5.873 \| good	25.481 \| good	27.313 \| good	0.665 \| good	2.293 \| good	0.176 \| good
2025-08-01T22:00:00.000Z	33 \| good	6.476 \| good	28.747 \| good	26.037 \| good	0.774 \| good	4.54 \| good	0.189 \| good
2025-08-01T23:00:00.000Z	38 \| good	6.939 \| good	30.789 \| good	23.222 \| good	0.884 \| good	6.786 \| good	0.202 \| good
2025-08-02T00:00:00.000Z	49 \| good	8.58 \| good	37.59 \| good	22.114 \| good	0.993 \| good	9.033 \| good	0.216 \| good
2025-08-02T01:00:00.000Z	49 \| good	9.075 \| good	39.884 \| good	19.487 \| good	1.111 \| good	10.668 \| good	0.228 \| good
2025-08-02T02:00:00.000Z	49 \| good	9.378 \| good	41.768 \| good	19.513 \| good	1.229 \| good	12.304 \| good	0.24 \| good
2025-08-02T03:00:00.000Z	52 \| moderate	10.442 \| good	46.136 \| good	19.847 \| good	1.347 \| good	13.94 \| good	0.252 \| good
2025-08-02T04:00:00.000Z	54 \| moderate	10.565 \| good	46.884 \| good	21.104 \| good	1.324 \| good	12.269 \| good	0.24 \| good
2025-08-02T05:00:00.000Z	54 \| moderate	11.398 \| good	50.259 \| good	21.47 \| good	1.301 \| good	10.598 \| good	0.228 \| good
2025-08-02T06:00:00.000Z	54 \| moderate	10.616 \| good	47.13 \| good	19.878 \| good	1.278 \| good	8.927 \| good	0.216 \| good
2025-08-02T07:00:00.000Z	52 \| moderate	9.536 \| good	42.675 \| good	19.625 \| good	1.178 \| good	7.761 \| good	0.209 \| good
2025-08-02T08:00:00.000Z	49 \| good	8.668 \| good	37.851 \| good	17.569 \| good	1.078 \| good	6.594 \| good	0.202 \| good
2025-08-02T09:00:00.000Z	38 \| good	6.812 \| good	30.184 \| good	15.941 \| good	0.978 \| good	5.428 \| good	0.194 \| good
2025-08-02T10:00:00.000Z	44 \| good	7.703 \| good	34.002 \| good	15.665 \| good	0.95 \| good	5.358 \| good	0.2 \| good
2025-08-02T11:00:00.000Z	52 \| moderate	9.699 \| good	43.331 \| good	16.914 \| good	0.922 \| good	5.289 \| good	0.205 \| good
2025-08-02T12:00:00.000Z	52 \| moderate	10.423 \| good	46.246 \| good	21.946 \| good	0.894 \| good	5.219 \| good	0.21 \| good
2025-08-02T13:00:00.000Z	52 \| moderate	10.153 \| good	44.967 \| good	27.288 \| good	0.873 \| good	4.323 \| good	0.2 \| good
2025-08-02T14:00:00.000Z	44 \| good	8.255 \| good	36.369 \| good	33.282 \| good	0.852 \| good	3.426 \| good	0.19 \| good
2025-08-02T15:00:00.000Z	44 \| good	7.999 \| good	35.127 \| good	36.329 \| good	0.832 \| good	2.53 \| good	0.18 \| good
2025-08-02T16:00:00.000Z	44 \| good	7.571 \| good	33.478 \| good	36.108 \| good	0.796 \| good	2.331 \| good	0.178 \| good
2025-08-02T17:00:00.000Z	44 \| good	8.43 \| good	37.055 \| good	32.39 \| good	0.761 \| good	2.131 \| good	0.176 \| 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?