Pollen Report Severity Levels FAQ: What do the Pollen Report "severity levels" and "predominant types" mean? What do the "severity levels" mean? The NC Division of Air Quality classifies pollen counts as "low", "moderate", "high" or "very high", based on frequency distributions of historical pollen counts. Our intent was for these respective categories to correspond approximately to the first, second, third, and fourth quartiles of typical data. People vary in their sensitivities to pollen, and the categories can also be thought of as indicators to the proportion of the population that is affected with allergy symptoms (seasonal rhinitis). Very few people are adversely affected by "low" pollen counts, while rather many may be affected by "very high" pollen counts. When a "Comment" lists more than one type of predominant pollen, is the order of the list significant? The pollen count reporters usually indicate more predominant pollen type before less predominant types, but this is more of a custom than a standard procedure or rule.