This research (2006) reports on the installation of indoor plants on total volatile organic compound (TVOC) levels, measured in 60 offices over two 5-9 week periods. The buildings used in this research were located in Sydney, Australia, and varied in age and usage.

VOCs are the cocktail of gases formed from the chemical off-gassing of internal furnishings and fittings, cleaning product usage and vehicle exhaust emissions. VOCs are recognised as a major component of indoor air pollution, causative in increasing sick-building syndrome (SBS) symptoms. These symptoms result in lower staff wellness through increased staff fatigue, illness and absenteeism. It is known that indoor VOC concentrations can be many times higher than those found outdoors.

During the course of the research, total VOC concentration levels were monitored and a range and quantity of indoor plants were installed. Among the key aims of this research were to investigate the optimum number and type of plants to bring significant VOC reduction and the impact that air conditioning has on this performance.

The research findings demonstrate that:

• When total VOC values rose above 100ppb, reductions of up to 75% were found in planted offices
• Indoor plants were equally effective under air-conditioned and non air-conditioned regimes

The researchers comment, that indoor plants offer a low-cost effective bioremediation method for indoor air pollution control.