Control of atmospheric oxygen depletion is achieved via injection of 99% pure N2 to reduce atmospheric O2 concentration to as low as 9%. N2 is generated onsite via a atmospheric oxygen molecular sieve-based N2 generator. Researcher access within the chamber environment while sub-ambient O2 experiments are running is possible as individual breathing air lines are piped into each of the six chambers. Atmospheric oxygen enrichment is achieved via an on-site, O2 generator operated under tightly controlled conditions and providing a maximum enrichment level of 23.5%. Users have no access to growth rooms during O2 enrichment.
Control of atmospheric SO2 within the walk-in chambers is achieved via injection of pure SO2 to increase concentration in the range of 1000 to 2000 ppb or accustom blend of 10% SO2 in air to increase concentrations in the range of 200 to 1000 ppb. Breathing air hoods attached to individual breathing air lines are available for researcher access to chamber conditions during elevated SO2 experiments. SO2 monitoring within the chamber environment is achieved using a Horiba APSA-370 analyzer
Control of atmospheric CO2 within chambers is achieved via injection of pure CO2 to increase concentration from ambient to a maximum of 2000 ppmV. A PP Systems WMA-4 CO2 Analyzer continuously monitors CO2 concentrations within each chamber.
Light intensity and uniformity
A range of within chamber light intensties from 300 to 1100 μmol is achieved via dimmable Metal Halide and three levels of supplementary tungsten incandescent lights. At 1m below the lamp barriers the maximum deviation in light intensity of any single point is +5.28% whilst the minimum deviation of any single point is -8.37%