Dust mite allergens range from 6 to 10 microns in size. In a study on dust allergen release by carpets, measurements of allergen concentration were taken at
varying heights of 4 inches, 24 inches and 42 inches above a carpeted floor. Samples were drawn above a heavily loaded classroom carpet during normal playtime.
They were taken under two conditions:
While vacuuming in a normal manner with a standard vacuum bag in place
Without the vacuum bag so that dust particles were freely released into the air
No trace of airborne allergens was found at any height during normal classroom activities.
However the presence of allergens was prominent when the vacuum bag was removed to allow free release into the atmosphere. Under this condition,
concentration of dust allergens peaked at a height of 4 inches above the carpeted floor with surprisingly negligible traces at heights of 24 inches and 42 inches,
approximating the breathing height of a child while seated and standing.
Consequent on this test it may be concluded that a negligible amount of allergens are released by a carpet during normal activities. However, collection of
surface allergen with scotch tape indicated a significant concentration of allergen on the carpet after vacuuming with the filtration bag removed. It would be safe to
conclude that allergens tend to settle on a carpet but do not get airborne during normal activities. By extension, carpets are less of a threat than commonly believed.
The risk would be further minimized with routine vacuuming.
