Air Monitoring Data


Helena Station



Previous Day 8/12/2017 Next Day


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PM2.5 NowCast Concentration Characterized by 24-Hour Health Effect Category

Hazardous Very Unhealthy Unhealthy Unhealthy for Sensitive Groups Moderate Good Hour Beginning (MDT)


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Health Effects Categories


Air quality data for the current hour are unavailable.
No health impacts are expected when air quality is in this range.
Unusually sensitive people should consider limiting prolonged outdoor exertion.
Active children and adults, and people with respiratory disease, such as asthma, should limit prolonged outdoor exertion.
Active children and adults, and people with respiratory disease, such as asthma, should avoid prolonged outdoor exertion; everyone else, especially children, should limit prolonged outdoor exertion.
Active children and adults, and people with respiratory disease, such as asthma, should avoid all outdoor exertion; everyone else, especially children, should limit outdoor exertion.
All children and adults should avoid or limit all outdoor exertion.
Hazardous
Very Unhealthy
Unhealthy
Unhealthy for Sensitive Groups
Moderate
Good
Data Unavailable

 

Explanation of Categories: Breakpoints and Associated Visibility for Particulate Concentrations.


Comparison to National Ambient Air Quality Standards (NAAQS)


24-hr Avg.
22.8
 µg/m3
NAAQS
35 µg/m3

Informational only - click here



Hourly Data Table Interpretation

Health Effects Categories are based on 24-hour average particulate levels, adjusted to a time-weighted NowCast to provide a real time assessment of current air quality. More Information about the NowCast method can be found here.

Hourly Data

Previous Day 8/12/2017 Next Day

Hour 1-Hour Avg PM2.5 NowCast Concentration
0:00-1:00 10.3Moderate   14.5
1:00-2:00 11.7Moderate   13.1
2:00-3:00 12.4Moderate   12.7
3:00-4:00 20.0Moderate   16.3
4:00-5:00 16.5Moderate   16.4
5:00-6:00 12.0Moderate   14.2
6:00-7:00 16.6Moderate   15.4
7:00-8:00 15.9Moderate   15.6
8:00-9:00 13.1Moderate   14.3
9:00-10:00 25.1Moderate   19.7
10:00-11:00 21.3Moderate   20.5
11:00-12:00 19.8Moderate   20.1
12:00-13:00 15.9Moderate   18.0
13:00-14:00 19.1Moderate   18.5
14:00-15:00 21.7Moderate   20.1
15:00-16:00 22.4Moderate   21.2
16:00-17:00 27.6Moderate   24.4
17:00-18:00 29.4Moderate   26.9
18:00-19:00 31.2Moderate   29.0
19:00-20:00 32.0Moderate   30.5
20:00-21:00 41.1Unhealthy for Sensitive Groups   35.8
21:00-22:00 36.9Unhealthy for Sensitive Groups   36.3
22:00-23:00 38.2Unhealthy for Sensitive Groups   37.2
23:00-0:00 38.8Unhealthy for Sensitive Groups   38.0

All data in µg/m3
DU = Data Unavailable



Health Effects Categories

Hazardous

Recommendation: All children and adults should avoid or limit all outdoor exertion.

Very Unhealthy

Recommendation: Active children and adults, and people with respiratory disease, such as asthma, should avoid all outdoor exertion; everyone else, especially children, should limit outdoor exertion.

Unhealthy

Recommendation: Active children and adults, and people with respiratory disease, such as asthma, should avoid prolonged outdoor exertion; everyone else, especially children, should limit prolonged outdoor exertion.

Unhealthy for Sensitive Groups

Recommendation: Active children and adults, and people with respiratory disease, such as asthma, should limit prolonged outdoor exertion.

Moderate

Recommendation: Unusually sensitive people should consider limiting prolonged outdoor exertion.

Good

Recommendation: No health impacts are expected when air quality is in this range.

Data Unavailable

Air quality data for the current hour are unavailable.

Data Disclaimer

The data presented here represent measurements of the concentrations of fine particulate matter in the ambient air that have been sampled continuously (except for internal machine checks) and then reported at the end of each hour. The data here are not final, and some modification of the data may subsequently occur as a result of quality assurance review. In particular, a disruption in normal analyzer operation may appear as a large spike on the graph, and as a value exceeding 800 in the table. These points are removed in the quality reviews. Representations of health risk are provided as general advisories, and are not substitutes for individual health awareness and the advice of medical professionals.