Receive Allergy Updates Via Email:

Receive allergy counts, news and information on allergy testing via email by joining our e-newsletter list.
Sign Up Now



Did you know?

Two-thirds of all physician office visits are for ear, nose, throat or allergic problems!

Today’s Pollen Count

Daily Pollen Count

September 25, 2023

Allergen m3 Record High
(This Day)
Record High
(All Time)
No Data

NAB: Reading the Charts

aaaai allergy pollen countsThe following Aeroallergen Network calculations are based on the data (per cubic meter) reported by all certified counting stations for trees, grasses, weeds and molds.

  • Median or 50th percentile (half of counts are below this point)
  • 75th percentile (75% of counts are below this point)
  • 99th percentile (99% of counts are below this point)

Based on these calculations, we suggest the following definitions for low, moderate, high and very high concentration levels:

NAB SCALE

* MOLD GRASS TREE WEED
0 Absent 0 Absent 0 Absent 0 Absent
1 – 6499 Low 1 – 4 Low 1 – 14 Low 1 – 9 Low
6500 – 12999 Moderate 5 – 19 Moderate 15 – 89 Moderate 10 – 49 Moderate
13000 – 49999 High 20 – 199 High 90-1499 High 50 – 499 High
>50000 Very High >200 Very High >1500 Very High >500 Very High

* These mold levels were determined based on outdoor exposure to natural occurring spores in the environment and should not be applied to indoor exposure which may represent an entirely different spectrum of spore types.

These definitions would allow comparison between sites across the country. They are based on ecological measurements, not health effects. However, assuming dose/response relationships are the same across the country, the definitions are probably more appropriate than a definition based on local numbers. This does mean that, for some stations, some categories will never be high.