Maintaining good IAQ in a building also requires careful managing of custodial, pest control and building engineering or contractor maintenance activities. Prior to initiating remodeling activities, discuss IAQ concerns with architects and contractors. Require that the materials and procedures used minimize airborne contaminants. If walls are being added or moved in the project area, or the number or distribution of occupants is to be greatly changed, modify the ventilation system to meet the new requirements. The best method to control indoor air contaminants depends on the source or sources causing the complaints.
Source control is generally the most cost-effective solution to the problem.
For example, environmental tobacco smoke-related complaints can be eliminated by prohibiting smoking within the building, or by isolating designated smoking areas and providing them with independent ventilation. Modification of the ventilation system may also be an effective method of resolving IAQ complaints. Contaminants can be diluted with outdoor air, or contaminants such as radon can be isolated or removed by changing air pressure relationships between adjoining areas. The increased cost is often no more than 5 percent of the original annual energy expenditure. The improved work environment more than pays for itself through improved occupant productivity.