Plants & Indoor Air Quality

With most people spending up to 80% of their time in indoor environments, be it at home, in the office, at school or university, it’s becoming more and more important to ensure our indoor environment is a healthy place. This is even more necessary as buildings become increasingly air tight and ventilation systems become closed loop. The term “building ecology” has been coined to describe the interaction between building environments and their occupants (Levin, 1981). A healthy building is one that does not adversely affect the health of its occupants or the larger environment.  An integral factor in this interaction is the indoor air quality of a building. Studies have shown that poor indoor air quality can substantially reduce the productivity and general health of workers in the office environment, with indoor air quality often being more polluted than outdoor air. Our appliances, decor, cleaning products and fixtures contain enormous amounts of potential polluting substances, so it is very important to ensure the internal air quality of all buildings is healthy and clean.

Volatile organic chemicals (VOCs- See Glossary) are a large factor in the occurrence of poor indoor air quality. VOC’s are organic chemicals which become volatile at normal room temperatures and can be highly toxic. They are emitted from many different office items, including a range of furniture, office appliances, fixtures and cleaning agents. Low ventilation is often blamed for the occurrence of high VOC levels. Presence of VOCs can lead to numerous health affects, ranging from irritation of eyes, nose and skin, headaches, fatigue and difficulty breathing with studies showing 5% to 40% of office workers have been affected, depending on the symptom (Fisk, 1997, 2000). Some of these VOCs are know Carcinogens (IARC).

Worldwide experience has recently been confirmed in Australia by research at the University of Technology, Sydney (UTS) that green plants are an effective way of reducing VOCs in internal air.

The indoor foliage plant species:

·        Kentia Palm (Howea forsteriana),

·        Peace Lily (Spathiphyllum ‘Petite’),

·        “Janet Craig’ (Dracaena deremensis),

·        Devil’s Ivy (Epipremnum aureum),

·        Queensland Umbrella Tree (Schefflera actinophylla,)

·         “Amate’ Spathiphyllum ‘Sensation’, ‘Petite’ and

·        Dracaena marginate

were all tested for their ability to remove VOCs from the indoor air. All seven plant types studied demonstrated benzene removal activity at similar rates. Kentia Palms were found to remove benzene up to 90% from a closed room after 24 hours. When ventilation was added to a room with a Spathiphyllum ‘Petite’ inside, the rate of benzene removal was improved up to 15%.

Studies in Norway and the Netherlands have shown that health complaints at work can be significantly reduced by the presence of plants. Whether these effects are physical or psychological (or a combination of the two) is uncertain. What is clear, though, is that symptoms associated with Sick Building Syndrome (SBS) can be dramatically reduced by the addition of good plant displays.

Another effective plant based air improvement technique has been shown to be the “breathing wall”. In this system, air is drawn through a porous wall kept constantly wet and covered with mosses and ferns, removing low levels of indoor air pollutants. An example of a breathing wall is shown here:

Integrating plants into the office environment has proven to be an effective, inexpensive, flexible and aesthetically pleasing biofiltration system that is self-sustaining as long as the plants are maintained adequately. Not only do they improve the atmosphere of any indoor environment, they help improve productivity, health and overall wellbeing of employees or your family. 

Green Wall in Your Room?

USA Today reports on what might be in your "Hotel of Tomorrow".

A wall that breathes: Envisioning some backlash against high-tech surroundings, designers conceived a back-to-nature hotel room with a lush "living wall" of grass-like vegetation. The wall, with a built-in watering and lighting system, would serve as an air filtering device, too.

Sources:

IARC: AGENTS REVIEWED BY THE IARC MONOGRAPHS, Volumes 1-88, International Agency for Research into Cancer, 2006

R. Wood, IMPROVING THE INDOOR ENVIRONMENT FOR HEALTH, WELL-BEING AND PRODUCTIVITY, Dept Env Sc., UTS, Sydney.

http://www.plants-in-buildings.com/whyplants.php

B. C. Wolverton,  How to Grow Fresh Air: 50 Houseplants That Purify Your Home or Office

http://www.insideplantslive.org/archives/cat_greenscaping.php “A wall that breathes”