1. Health
You can opt-out at any time. Please refer to our privacy policy for contact information.

Monitoring Pollen Counts & Mold Counts

Tips for Avoiding Pollen and Mold


Updated: June 3, 2008

Ragweed pollen

Ragweed pollen

Source: American Academy of Allergy, Asthma and Immunology
Monitoring pollen counts and mold counts on a daily basis during the seasons when they are present is one of the most proactive steps you can take to control your asthma. When you know that pollen or mold levels are high outside, then you'll know to stay inside as much as you can to avoid exposure to these common outdoor asthma triggers. Pollen are tiny, egg-shaped cells found in flowering plants. Pollen spores are spread far and wide through the air by winds and air currents. There are different types of pollens, but the kind that causes the most problems for people with asthma and allergies is light, small, powdery and dry. The pollen typically comes from one of three sources:
  • Trees, in the spring
  • Grasses, in the summer
  • Low-lying weeds, such as ragweed, in the late summer and early fall
Molds can grow both outdoors and indoors, but when you hear about mold counts, they're usually referring to the outdoor type. Outdoor mold spores may be found any time of the year, but are most common during hot and humid conditions, such as those found in the late summer or in the southern regions of the United States. Outdoor molds are most often found in piles of dead leaves, soil, vegetation and rotting wood.

What Are Pollen Counts and Mold Counts?

A pollen count is nothing more than a measurement of how much pollen is in the air. It is expressed in terms of a concentration of pollen in the air in a specific area at a certain point in time. The exact measure is grains of pollen per cubic meter over a 24 hour period.

Pollen counts are collected using a special sampling device that is typically placed on a rooftop several stories above the ground. The device has a sticky surface that collects grains of pollen from the air. Since pollen is so easily spread over a wide area, a sampling taken in one area is usually considered valid for a large area, even an entire city.

Mold counts, like pollen counts, are a measurement of how many mold spores are in the air in a certain area at any given point in time.

Why Are Pollen Counts and Mold Counts Important to People With Asthma?

When you have allergic asthma, avoiding your triggers is the best action you can take to keep your asthma under control. When pollen and mold counts are high, you should stay indoors as much as you can. But you can't see pollen or mold with the naked eye. So the only way to know when the levels are high is to monitor official pollen counts or mold counts.

Even better than a current pollen count or mold count is a mold or pollen forecast. A forecast is a prediction of where the counts are headed, so it is more useful in planning your day or days ahead. Forecasts are based on current counts and weather conditions, as well as historical trends.

Where Can You Get Accurate Pollen Count & Mold Count Information?

You can get pollen counts from a number of different sources, both locally and online. During spring and summer, many local radio or TV stations may report pollen and mold levels. These may or may not be accurate, depending on where they are getting their information. The best and most current places to get pollen counts and mold counts may be online:

  • Pollen.com, which specializes in pollen level monitoring, has up-to-the-minute reports for every area and will even email you your local counts on a daily basis.
  • National Allergy Bureau, a division of the American Academy of Allergy Asthma & Immunology, has both pollen and mold counts by region.
  • Weather.com, the website for The Weather Channel, offers both geographically-specific pollen counts and mold counts.

In addition to knowing your local counts, you can take other measures to limit contact with pollen and with mold.

Keeping yourself informed about your local pollen / mold counts is one of the best ways to limit your exposure to them. You will probably not be able to avoid them totally. But hopefully, you will be able to control your asthma symptoms with attention to this detail.


"Tell me about pollen counting." 2008. Pollen.com. 31 May 2008.

"NAB: Reading the Charts." National Allergy Bureau. 01 Jun 2008.

  1. About.com
  2. Health
  3. Asthma
  4. Control & Prevention
  5. Asthma Prevention
  6. Monitoring Pollen Counts and Mold Counts - How to Monitor Pollen Counts

©2014 About.com. All rights reserved.

We comply with the HONcode standard
for trustworthy health
information: verify here.