Your gallery must maintain good air quality to preserve its content. Works of art and antiques can deteriorate due to the presence of dust and humidity, also due to chemical reactions caused by concentrations of nitrogen dioxide and ozone. For example, layers of dust not only discolour objects, but also wear some materials out, such as painting canvas. You should also consider the wellbeing of those who visit your gallery. The concentrations of gases caused by cleaning materials will not only affect the objects you display, but also harm the health of those who breathe them.