The Houston Health Department laboratory uses an instrument called the Burkard Spore Trap to measure air samples in order to provide a daily report and recorded message for the pollen and mold spore count within the area. The Burkard Spore Trap collects pollen and mold spores 10 liters/ min, 24 hours a day.  It is located on the roof of the laboratory. 

The following ranges are based on the data reported by all counting stations for weeds, grasses, trees and mold according to the National Allergy Bureau. 

Weed pollen is measured per cubic meter of air.

• 1-9 pollen per cubic meter of air or less = Low
• 10 to 49 = Medium
• 50 to 499 = Heavy
• Greater than 500 = Extremely Heavy  

Grass pollen is measured per cubic meter of air.

• 1-4 pollen per cubic meter of air or less = Low
• 5 to 19 = Medium
• 20 to 199 = Heavy
• Greater than 200 = Extremely Heavy

Tree pollen is measured during the tree pollen season of mid-January through mid-April.  Cedar Elm tree pollen is measured in September and October.  All tree pollen types are reported by HDHHS laboratory.

• 1 to 14 pollen per cubic meter of air = Low
• 15 to 89 = Medium
• 90 to 1499 = Heavy
• Greater than 1500 = Extremely Heavy

Mold spores are measured per cubic meter of air.

• 1 to 6499 = Low
• 6500 to 12999 = Medium
• 13000 to 49999 = Heavy
• Over 50000 = Extremely Heavy

The HHD laboratory reports all major types of mold spore irritants.

• Alternaria
• Aspergillus 
• Basidiomycetes
• Cladosporium
• Dematiaceous conidia  
• Epicoccum
• Drechslera/Helminthosporium