The Numbers Game

• Disparity in opinion regarding what count is normal / acceptable

• Health Canada Indoor Air Quality in Office Buildings 1993, 600 samples, average 40cfu/m3 in Federal Buildings

• US Non Residential Buildings 1993 - 2000 samples, 75% of which yielded fungal counts less than 178cfu/m3

• Species present and comparison with outdoor mycoflora more important than absolute numbers