The Perils of Vacuum Cleaners
A vacuum cleaner is a device that uses an air pump to create a partial vacuum to suck up dust and dirt, usually from floors, and optionally from other surfaces as well. Does not sound so bad does it? Some vacuum cleaners — those basic tools for maintaining a clean indoor environment in homes and offices — actually contribute to indoor air pollution by releasing into the air bacteria and dust that can spread infections and trigger allergies, researchers report in a new study. It appears in the ACS' journal Environmental Science & Technology. Lidia Morawska and colleagues explain that previous studies showed that vacuum cleaners can increase levels of very small dust particles and bacteria in indoor spaces, where people spend about 90 percent of their time. In an effort to provide more information about emission rates of bacteria and small dust particles, the scientists tested 21 vacuum cleaners sold in Australia. The vacuums came from 11 manufacturers, included those marketed for household and commercial use, ranged in age from six months to 22 years and cost from less than $100 to almost $800. They looked at the effects that age, brand and other factors had on the amount of small particles and bacteria released into air.
All of the studied vacuums released some fine dust and bacteria into the air. Surprisingly, vacuums with so-called High-Efficiency Particulate Air (HEPA) filters in some cases released only slightly lower levels of dust and bacteria. Newer and more expensive vacuum cleaners were generally less polluting than older or less expensive models.
HEPA is a type of air filter. Filters that are awarded the HEPA accolade are used in various locations, whether in medical facilities, automotive vehicles, airplanes, home filters, or wherever very pure air is sought. To qualify as HEPA by government standards, an air filter must remove 99.97% of all particles greater than 0.3 micrometer from the air that passes through.
Vacuuming can be a source of indoor exposure to biological and nonbiological aerosols, although there are few existing data that describe the magnitude of emissions from the vacuum cleaner itself. The study sought to quantify emission rates of particles and bacteria from a large group of vacuum cleaners and investigate their potential variables, including temperature, dust bags, exhaust filters, price, and age.
Vacuum cleaner emissions were determined to contribute to indoor exposure for nonbiological and biological aerosols when vacuuming, and this effect may vary markedly depending on the vacuum used.
In essence the vacuum cleaner could clean large dirt but was not as effective on smaller aerosols.
For further information: http://pubs.acs.org/doi/abs/10.1021/es202946w