Energy conservation vs health. The air quality picture

With the advent of the concepts of efficient energy use   focus   has   shifted   towards   buildings   becoming  more air tight and having lower levels of ventilation. This is due to the fact that as buildings become better insulated   and   conduction   heat   loss   is   reduced   the  proportion of heating and air conditioning load due to ventilation has increased and may offer the largest scope for reducing energy demand. This may have a detrimental effect on internal air quality (IAQ) and compounds existing environmental issues such as out gassing from materials in new buildings. At the same time environmental standards and expectations have risen as has the technical capability to evaluate their effects   through   epidemiological   studies.   Good  environmental quality is a fundamental human need, absence   of   which   affects   health   and   productivity.  Many   occupants   express   annoyance   about   modern buildings and terms such as sick building syndrome (SBS)   are   used   to   describe   the   problem.  Deterioration   of   IAQ   has   been   evident   from   an increase in occupant complaints and an increase in breathing   related   sicknesses   in   recent   years.   With  predicted   substantial   growth   of   the   urban environment the problem will only be exacerbated in the future. A simple and effective  solution  to  the  problem of  deficient IAQ is increasing ventilation but increasing the amount of inlet fresh air has direct bearing on energy   load.   Another   important   factor   is   the  ventilation   scheme   (mechanical,   natural,   mixed­mode). This paper looks at the relationship between good IAQ, ventilation, associated energy overheads and   carbon   emissions.   Also   identified   are   best  practices that optimise the performance of a building in relation to this issue.