Assessment of vacuum cleaners and vacuum cleaner bags recommended for allergic subjects

Background: High-quality vacuum cleaners and vacuum cleaner bags are often recommended to allergic patients as a means of reducing indoor allergen exposure. A number of vacuum cleaners on the market today claim to capture 99.9% of particles 03 mu m or larger entering the vacuum cleaner, and many vacuum cleaner bags are now being sold as microfiltration bags. Objective: The purpose of this study was to compare the allergen-trapping abilities of vacuum cleaners and to use a new technique for testing vacuum cleaner bags that are recommended for allergic patients. Methods: Vacuum cleaners were tested in an 18-m(3) laboratory room permeated with dust containing high levels of cat allergen by using techniques previously described. Air was sampled with parallel filters in conjunction with a particle counter. The filters were assayed by ELISA for cat allergen (Fel d 1), Vacuum cleaner bags mere tested by using a modified dust trap to pull sieved house dust containing a known amount of Fel d 1 across the material used for the bag. Allergen passing through the bag mas trapped on a filter covering the exit of the trap and analyzed for Fel d 1, Results: In general, vacuum cleaners designed for allergic patients leaked lower amounts of allergen (<0.5-4.04 ng/m(3)) than that found in our previous studies (<0.5-100 ng/m(3)). Single-layer vacuum cleaner bags performed poorly (1250-2640 ng recovered) compared with most of the 2- and 3-layer microfiltration bags (0.53-2450 ng recovered). The range of allergen recovered from the 2-layer bags (0.93-2450 ng recovered) highlighted the variability found between manufacturers. Conclusion: The results suggest that although allergen leakage has been reduced, there is still room for improvement. A method of testing allergen leakage by using Fel d I should be; applied to vacuum cleaners and bags recommended for allergic patients.