The controller should be able to add or remove carbon dioxide during either light, dark, or both periods. Ventilation Air must be moved to carry heat away from the plant, to carry carbon dioxide to the plant, and to minimize temperature gradients in vertical and horizontal directions. Air flow over plant canopy should be maintained around 0.15 - 0.5 m per sec. Makeup air is taken from outside the chamber and preferrably mixed with some chamber air prior to it entering the growth area. Filters are needed for chambers used in pollution studies.
Extra power is required to force air through very fine or absolute filters.
If an electric supply is already installed, the available amperage should also be indicated. Water, Steam, Pressurized Air, and Vacuum Water supply pipes and drains and the distance of each from the intended installation area should be specified. If deionized water is to be plumbed into system, the available flow should be specified. Distilled or deionized water can be used for humidification, nutrient solutions, leaching of soil, and, if available in sufficient quatinty, the cooling tower. Describe any available pressurized air and vacuum systems so chamber manufacturer can make use of these systems if needed.