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Houseplants really do clean and humidify indoor air.
To lower stress, many physicians recommend a relaxing hobby like gardening. But cultivating plants indoors may also lower the risk of asthma, allergies and "sick building syndrome" (SBS).
The term is used to describe a variety of symptoms, including dizziness, headaches, coughing, sneezing, nausea,, irritation of eyes, nose and throat, chronic fatigue, dry skin and flulike symptoms, experienced by people working in "sick" buildings.
A building is considered “sick” when at least 20% of its occupants suffer persistent symptoms that disappear when they go outside.
No specific cause of SBS has yet been identified, although it is frequently associated with modern, sealed, air-conditioned buildings. Research has suggested links with poor ventilation, dust mite allergies, airborne pollutants and inadequate lighting to name but a few.
Most North Americans live in cities, where vehicle-polluted outdoor air enters buildings and is further polluted, mostly by Volatile Organic Compounds (VOCs) from furnishings, fittings and occupants. Trace amounts of over 300 VOCs have been identified in indoor air. A 1994 CSIRO review found that air inside homes could be 5 to 7 times more polluted than outside.
The chemical that causes most people difficulty is formaldehyde, an extremely irritating gas. Millions upon millions of North Americans suffer from chronic breathing problems, dizziness, rash, headaches, sore throat, sinus and eye irritation, and nausea caused by daily exposure to low levels of formaldehyde emitted (outgassed) from common building materials (such as plywood, particleboard, and paneling), furniture, upholstery, and adhesives in carpeting and wallpaper.
The energy crisis of the 1970s led many Americans to superinsulate their homes and offices against energy loss. Man-made materials like particle board, synthetic fibers and plastic--which harmfully emit formaldehyde, trichloroethylene (TCE), benzene and other volatile organic compounds (VOCs) over years of exposure--have also become ubiquitous indoors. Paints, varnishes, household cleaners, adhesives, carpeting and tobacco smoke are other common VOC-emitters.
The relative humidity of air inside buildings can be extremely low, often below the recommended human comfort range of 40 to 60%. This is especially true when buildings are heated; the relative humidity drops as the air is warmed unless supplementary moisture is added. Under these conditions the building’s occupants may become fatigued and more susceptible to SBS and other ailments.
City-dwellers spend 90% of their time indoors,
so indoor air quality becomes a major health consideration.
Air filters are adequate at capturing particles like dust and dander, they do little to eliminate noxious VOCs.
Mechanical humidifiers are often used to increase relative humidity levels in buildings. However, these devices can be both noisy and unsightly and can become contaminated with micro-organisms. Plants on the other hand release water vapour naturally through transpiration and evaporation from the soil surface. Research has shown that even a modest level of office planting can raise the relative humidity by several percentage points.
Dust is significantly lower throughout the rooms when plants are present than when they are absent. Dust is reduced by as much as 20% with plants
Whatever the cause(s) of SBS, plants undoubtedly have a role to play in maintaining good air quality.
In 1984, NASA senior research scientist Dr. Bill Wolverton tested houseplants for their ability to maintain clean air for future habitable lunar bases. Testing in sealed chambers, Wolverton found that philodendrons and golden pothos were excellent formaldehyde controllers; gerbera daisy and chrysanthemums were impressive benzene purgers; pot mums and peace lilies were highly rated for TCE removal. His initial findings suggested that one to three mature plants were enough to improve the air in a 100-cubic-foot area. Another 1989 NASA study concluded that tested houseplants removed up to 87 percent of toxic indoor air within 24 hours. A 1994 German study further reported that one spider plant could, in six hours, detoxify a 100-cubic-foot room laden with formaldehyde. Further tests showed English ivy benefited smoking areas, bamboo palm eliminated carpet odors, and the snake plant cleared household cleaner smells. Wolverton's personal favorites are the lady palm, peace lily and "Janet Craig" dracaena--"because they're easy to grow, resist insects and work wonders" for a variety of pollutants. His latest book, How to Grow Fresh Air: Fifty Houseplants that Purify Your Home or Office additionally lists the areca and bamboo palms, English ivy and rubber plant as top pollutant controllers. Because indoor air varies, a good mixture works best, researchers advise.
Findings indicate that an adequate installation of interior plants in a modern, sealed
office structure could save U.S. companies billion via contributions to improved
indoor air alone.
Researchers William J. Fisk and Arthur H. Rosenfeld, Lawrence and Berkeley National
Laboratory (LBNL), Berkeley, CA found that U.S. Companies could save as much as
billion annually by preventing sick-building illnesses and an additional billion
in worker performance improvements by creating offices with better indoor air. The
same study verified that 40% of all sick days are IAQ-related.
Домашние растения необходимы в каждом доме!
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