Johannesburg - Indoor plants clean and purify the air that you breathe, says US space agency Nasa. This was discovered during research aimed at finding ways to purify contaminated air in a space capsule. Nasa’s latest experiments prove that indoor plants can remove pollutants that build up in an enclosed chamber.
The findings have implications for office workers in air-conditioned, poorly ventilated, modern high-rise buildings.
Microscopic particles of formaldehyde, benzene and ozone are emitted from building materials, furniture, carpets, copying machines, and cleaning solvents.
In poorly air-conditioned, sealed buildings the pollutants are unable to disperse into the atmosphere and their levels of concentration increase. Eventually, people complain of itchy eyes, skin rashes, drowsiness, respiratory problems, sinus congestion, headaches and a variety of allergies – characteristics associated with the “sick building syndrome”.
In the Nasa studies, a dozen common indoor plants were placed in sealed, plexiglass chambers. Formaldehyde, a toxic chemical, was leaked into the chambers. Within 24 hours, the plants had removed 80 percent of the formaldehyde molecules from the chamber.
From these findings, scientists estimate that one plant can clean and purify an area comprising 10m2.
Flowering plants such as the chrysanthemum have a high metabolic rate and are able to remove toxic molecules quickly. Foliage plants tend to work slower, but their permanency makes them better suited to interior environments.
Indoor plants also have a direct influence on productivity levels in offices on account of higher levels of employee satisfaction, reduced stress levels and improved physical health.
Studies in the Netherlands, US and the UK show evidence of a direct correlation between the presence of indoor plants in the workplace and improved productivity.
Indoor plants can contribute positively to improved organisational productivity by improving the physical and the emotive wellbeing of employees.
“Active and passive interaction with plants can change human behaviours, attitude and physiological responses,” says Virginia Lohr from Washington State University. During her research, participants with similar abilities undertook computer tests, some in rooms populated with plants and others without.
The reaction time of the participants occupying rooms with indoor plants was 12 percent higher. People surrounded by plants were shown to have lower blood pressures, a significant indication of lower stress levels.
In a study at Surrey University, sensors were attached to the skin of the participants to measure skin conductivity, heart rate and blood pressure while being subjected to mental arithmetic tasks while being intentionally distracted.
The tests showed that stress levels for those in rooms where plants were present were lower and that the recovery rate during the post-test period was quicker than those in the empty environment.
Plants on Mars
More recent Nasa studies indicate that indoor plants will be essential to any missions to Mars. It is now proved that indoor plants filter and clean the air by removing up to 87 percent of volatile organic compounds (VOCs).
These compounds are emitted by a wide array of products numbering in the thousands. Examples include paints and lacquers, paint strippers, cleaning supplies and even pesticides.
Allergic reactions, headaches, nausea, asthma and other respiratory-tract irritations are common indicators of VOCs. The negative effect of these illnesses on productivity in the workplace is high, increasing absenteeism and a more recently identified malaise, presenteeism. Presenteeism, a modern word that seems to be finding its way into many modern research documents, is the act of attending work while sick.
A study undertaken by the Cornell Institute for Health and Productivity studies in New York, estimated that productivity losses as a result of presenteeism could be as high as 60 percent of the total cost of worker illness.
According to the Cornell researchers, this cost could well be higher than the cost to the employer of general absenteeism.
Many factors positively influence the ability of a workforce to operate at the highest level. These need to operate in combination to optimise personal and organisational output.
The evidence in the studies supports the importance of incorporating indoor plants into the office design. The higher levels of employee satisfaction, the reduced stress levels and improved physical health are sure to have a direct influence on productivity levels.
If breathing clean air is an important personal concern, indoor plants will no longer be a luxury, but a necessity in homes and offices.
GENERAL GARDEN TIPS
Great care should be taken not to disturb the roots of a bougainvillea when planting. The easiest way is to cut around the base of the bag and remove it, then carefully lower the plant in its plastic sleeve into the hole. Only then should the sleeve be slit and removed. Water newly planted bougainvillea regularly until well established.
A rose garden can look more interesting between flushes if under-planted with herbs such as aromatic sage, origanum, lavender or dianthus. Other ways of growing herbs where gardening space is limited is in pots, hanging baskets and window boxes on balconies and patios. Growing herbs in raised beds is a way of providing drainage for herbs that do not like “wet feet”. Cutting back growth will encourage a more compact shape.
Cut lawns little and often. Keep lawnmower blades raised, as exposing roots to hot sun will result in burning. Fertilise with a commercial lawn fertiliser, always watering in thoroughly after application. Trim edges once a week to prevent runners from growing into beds.
Extend the blooming season well into autumn by planting seedlings of summer annuals, such as marigold, salvia, celosia, vinca and verbena. - Saturday Star