Hourly PM Concentrations for Hurricane Affected Areas

Note: EPA no longer updates this information, but it may be useful as a reference or resource.

In order to provide the public in hurricane affected areas with air quality information as close to real time as possible, the graphs below present hourly concentrations of fine particles. If the line tracking hourly concentrations is below the 40 ug/m3 screening level, for most of the day, but peaks above it for an hour or two, the daily average is likely to be below the screening level. Conversely, if the hourly concentration line spends most of the day above the screening level, the daily average is likely to be above the level of concern for sensitive groups.

Airborne particles like smoke and dust are solids and liquid droplets of different sizes suspended in the air. EPA sets the screening level to caution sensitive groups, including people with heart or lung disease, older adults, and children. For fine particles, that level is 40 ug/m3 for 24-hour average exposure. This level is based on EPA's Air Quality Index. Above this level, we recommend that sensitive groups reduce their exposure.

Shorter term peaks are also of potential concern for sensitive groups. The screening level for the general population is 65 ug/m3 over a 24-hour period. Most healthy adults and children are expected to recover quickly from any symptoms of short-term exposure like coughing, wheezing, or eye and throat irritation.

Currently, there are four monitors reporting data:

• Kenner, LA
• Gulfport, MS
• Pascagoula, MS
• Stennis, MS

To view data, select the monitor location from the "SITE" drop-down menu. You can narrow your search by selecting the pollutant from the "PARAMETER" drop-down menu. To view historical graphs and data for a monitor, select a date from the calendar. Days with reported data are highlighted in blue.