The study was designed to measure airborne particles of cat allergen (Fe! 1) under various circumstances and their impact upon allergy and asthma sufferers. Among other findings, the study examined the impact of two different "allergy vacuum cleaners" on the airborne particles generated by house cats that most commonly cause allergic reactions.

Testing with two types of vacuum cleaners, one a water-filtering vacuum system and the other a FIEPA (High Efficiency Particulate Air) vacuum cleaner manufactured by Nilfisk-Advance America, Inc., found an increase in airborne cat allergens as a result of using the water-filtering vacuum system. The HEPA-filtered vacuum cleaner, on the other hand, effectively reduced the number of allergens in the carpet during vacuuming and caused no increase in airborne particles from the vacuuming process.

"The sharp increase in airborne cat allergen associated with small particles when the water-filtering vacuum system was used was shown to be due to the formation of fine droplets by the machine. This result leaves little doubt that this type of vacuum cleaner system would not be suitable for patients allergic to cats," according to the study in the February issue of the respiratory journal, published by the American Lung Association.

"In contrast, the HEPA-filtered vacuum cleaner effectively contained the allergen," the study reported.

Previous reports have advised allergy sufferers against using their home vacuum cleaners because the mere act of vacuuming tends to stir up the allergens in the home and in some cases, exacerbate the suffering.