This report presents an evaluation of emissions from indoor building materials that may cause health damage to the people who occupy the building, since these materials emit toxic chemicals into the air and indoor surfaces. This report presents a case study which evaluates Gypsum Boards, frequently used in the construction of dividing walls and ceilings. The experimental part of this report is based on a three-dimensional space that simulates a common room; for example, a classroom or a workstation. The indoor environmental conditions, such as ventilation, temperature, and humidity, affect chemical emissions from building materials. The technical methodology used, is based on the comparison of conventional materials and alternative materials with similar characteristics and different composition, using similar testing methods, environmental conditions, and instruments and tools. This is a very important report to understand problems related to environmental pollution, specifi cally of air and its effects indoors, directly on public health, and indirectly on building systems and selection of materials. The tests conclude that alternative materials (with recycled content) are better than traditional ones, because they reduce indoor pollution.