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Air Quality Monitoring

National Ambient Air Quality Standards (NAAQS)

The Clean Air Act (CAA) requires the Environmental Protection Agency (EPA) to set National Ambient Air Quality Standards (NAAQS) for six criteria pollutants. Ozone and particulate matter are two of these pollutants.  EPA works with partners at state, local, and tribal air quality agencies to meet these standards.  In Michigan they primarily work through the Michigan Department of Environmental Quality (MDEQ).

Under the CAA, as amended in 1990, each state must develop a plan describing how it will attain and maintain the NAAQS.  In other words, how it plans to clean up polluted areas and keep them clean.  This plan is called the State Implementation Plan (SIP) and is required under Section 110 of the CAA (40 CFR Part 51, Subparts F & G).  In general, the SIP is a collection of programs, including:

  • a monitoring program, which is a collection of monitoring devices which provide actual measurements of the concentrations in the air, to identify whether an area is meeting the air quality standards
  • air quality calculations and computer modeling, which are used to predict future trends and the effects of emission reduction strategies
  • emissions inventories, which describe the sources and categories of emissions to the air for a given pollutant, and how much is emitted by each source or source category

Ozone Monitoring

A network of five air quality monitoring stations, located in Evans, Grand Rapids*, Holland, Jenison, and Muskegon, continually monitor ozone levels in West Michigan from April 1st through September 30th. (*The Grand Rapids station monitors ozone year-round and posts the data on the web.) The MDEQ and the EPA average the data from these monitors over eight hours and compare it to the NAAQS. At each monitoring station, the fourth highest eight-hour value averaged over three years is not to exceed 70 parts per billion (ppb). If over three years, the average of the highest ozone values is over 70 ppb, the NAAQS is violated.

For a map of these monitoring stations, click here.

Particulate Matter Monitoring

A network of five air quality monitoring stations, located in Grand Rapids (2), Muskegon (monitor will be shut down July 1, 2013), Holland, and Jenison, monitor West Michigan particulate matter levels year-round. The MDEQ and EPA use an annual standard and a daily standard to determine compliance with the particulate matter less than 2.5 um in diameter (PM2.5) NAAQS particulate matter violations. The EPA adopted a new annual standard of 12.0 micrograms per cubic meter (µg/m³) in December, 2012. To attain this standard, the three-year average must not exceed 12.0 µg/m³. The previous standard of 15 µg/m³ is also still in effect. To attain the daily standard, the three-year average of the 98th percentile of 24-hour cencentrations at each monitor must not exceed 35 µg/m³.

For a map of these monitoring stations, click here.

Monitoring and Clean Air Action Days

To help protect the health of the community, a Clean Air Action Day will be called on days when widespread ozone concentrations are forecast to exceed 70 ppb over an eight hour period or particulate matter levels are forecast to exceed 35 µg/m³ over a 24-hour period throughout the area.

The Air Quality Index (AQI) is a tool used to communicate air quality to the public that is separate from the ozone and PM2.5 NAAQS. The AQI, normalized by pollutant concentration, ranges from good (green), moderate (yellow), unhealthy for sensitive groups (orange), to unhealthy (red).

For current air quality information, you can view ozone monitors or particulate matter monitors (MDEQ web site) to see real time data from monitoring stations around the state.

Clean Air Action Day Notifications in West Michigan

Year

Total CAA Days

Clean Air Action! Days

2017   June 10 June 11 June 12            
2016 10 May 23 June 10 June 11 June 19 June 25 July 21 July 23 Aug 4 Aug 10
    Aug 11                
2015 4 July 18 Aug 16 Aug 17 Sept. 6          
2014 3 July 20 July 21 July 22            
2013 2 Aug 20 Aug 21              
2012 25 May 24 May 27 June 9 June 10 June 15 June 16 June 19 June 20 June 28
    June 29 July 2 July 3 July 4 July 5 July 6 July 7 July 13 July 15
    July 16 July 17 Aug 4 Aug 24 Aug 25 Aug 30 Aug 31    
2011 8 June 7 June 8 July 2 July 17 July 20 July 21 Sept. 1 Sept. 2  
2010 5 July 4 Aug 13 Aug 29 Aug 30 Aug 31        
2009
3 June 24 Aug 15 Aug 16            

Previous Ozone Action Day Notifications in West Michigan

Year

Total OA Days

Ozone Action! Days

2008
5
July 11
July 17
July 18
Aug 21
Sept 2
       
2007
6
June 16 June 18 Aug 1 Aug 2 Aug 28 Sept 5      

2006

6

June 17

July 16

July 17

July 31

Aug 1

Aug 2

 

 

 

2005

11

June 8

June 9

June 10

June 24

June 27

July 11

July 12

Aug 2

Aug 3

 

 

Aug 8

Aug 9

 

 

 

 

 

 

 

2004 1
June 8
               

2003

8

June 22

June 23

June 24

June 25

July 3

Aug 15

Aug 20

Aug 21

 

2002

15

June 9

June 10

June 20

June 23

June 24

June 25

June 30

July 1

July 15

 

 

July 16

July 17

July 31

Aug 1

Sept 8

Sept 9

 

 

 

2001

12

June 13

June 14

June 26

June 27

June 28

June 29

June 30

July 31

Aug 1

 

 

Aug 7

Aug 8

Aug 9

 

 

 

 

 

 

2000

4

June 9

June 10

Aug 31

Sept 1

 

 

 

 

 

1999

20

May 29

June 6

June 7

June 8

June 9

June 10

June 22

June 25

June 26

 

 

June 27

July 3

July 4

July 5

July 15

July 16

July 23

July 30

Sept 3

 

 

Sept 4

Sept 5

 

 

 

1998

11

May 28

June 20

June 25

June 26

June 27

July 13

July 14

July 15

July 20

 

 
July 21
Sept 5

 

 

 

1997
11

June 24

June 27

June 28

June 29

June 30
July 1
July 12

July 13

July 14

 

 

July 17

July 26

 

1996

6

June 28

June 29

Aug 5

Aug 6

Aug 7

Sept 6

1995

16

June 6

June 7

June 15

June 16

June 17

June 18

June 19

June 20

June 21

 

 

July 12

July 13

July 14

July 15

July 30

July 31

Aug 12
   


More information

Realtime Ozone and Particulate Matter Data – view current ozone and particulate matter information from MDEQ air monitoring sites.

Air Quality Standards (NAAQS) for Ozone and Particulate Matter
– find out what air quality levels are used to define "clean air" for ozone and particulate matter under the Federal Clean Air Act. For more information on NAAQS standards, please click here.

Designations for Ozone and Particulate Matter – find out if a geographic area you are interested in meets clean air standards for ozone or particulate matter.

Regulatory Actions for Ozone and Particulate Matter – find EPA links to proposed and final rules, fact sheets, and other rulemaking documents.

Controlling Particle Pollution – find information, and links to information, on work that is underway to reduce particles in the air, both by reducing directly emitted particles and by reducing emissions of pollutants that are gases when emitted but which form particles in the atmosphere.

The West Michigan Clean Air Coalition is a partnership of businesses, academic institutions, government agencies, industry, and non-profit organizations in Kent, Ottawa, Muskegon, and Kalamazoo counties working together to achieve cleaner air in the region through the education and promotion of voluntary emission reduction activities.

©2006 West Michigan Clean Air Coalition. All Rights Reserved. | E-Mail the Webmaster | Page last updated Sunday, June 11, 2017.