• check a painting for signs of damage. is the paint flaking or powdering? can you notice mould growth or small insect holes? if such deterioration is noticed, it is advisable to request a paintings conservator for advice and treatment to limit further irreversible deterioration. however, if no deterioration is noted, then it is recommended to inspect the back of the painting too in order to observe if there is any active biological deterioration – which also has to be reported to a conservator. when inspecting the reverse side of paintings, it is important to handle the painting with great care. grab the painting firmly from its outer decorative frame using soft cotton gloves to prevent abrasions. In addition, move the painting slowly to prevent vibrations and place it carefully on a table. do not handle the painting alone if the painting is too big and heavy. try to limit handling and transportation of paintings – as much as possible – to prevent accidental damages.          
• cleaning paintings from dust. if the painting is dusty, it is always advisable to clean it regularly because dust can promote biological deterioration and, of course, affect its visual appearance. the removal of dust can be performed only when the painting do not show signs of flaking or powdering paint because there would be the risk of loosing further paint. the use of textile is not advisable to remove dust as the textile gradually scratches the painting with the rubbing action. instead, a small and soft brush can be used to brush away the dust, possibly using an air-blowing brush like the ones used for the cleaning of photographic camera lenses. never use detergents, water or any other liquids for such cleaning. in addition, if the painting needs to be stored (rather than exhibiting it), then the painting can be covered with a soft non-abrasive textile to limit further dust accumulation on the painting and to limit the need of frequent dusting.
• check if the painting is exhibited or stored in an adequate environment. in most cases, the environment is the most damaging factor. the following list of advices can be used to improve the environment of a painting:
• do not hang paintings on a humid wall, particularly if the wall shows water stains.
• try to hang paintings on interior walls rather than exterior walls. exterior walls are prone to change their moisture and heat content more than interior walls by the (external) weather conditions.
• isolate paintings from the wall. Use small spacers that can keep paintings at least 2cm away from the wall. it must be assured that the entire reverse side of the painting is kept away from the wall (and not just the top or bottom part of the painting). 
• keep paintings away from doors and windows, particularly from external apertures that are often kept open.
• paintings have to be exhibited and stored in locations that are never exposed to direct sunlight.
• paintings should also be kept inside rooms that do not feature large windows (that can permit considerable sunlight to enter and heat the internal space of the room). it is also advisable to screen windows from outside – such as with louvered windows – and covered with light-coloured curtains from the inside.
• when illuminating paintings with artificial light, it is important to use low-intensity light sources. it is recommended to use light sources that emit the least amount of heat and that can provide diffused lighting. moreover, do not place illumination sources immediately next to the painting (the cylindrical light source that is often used on top of paintings may be attractive but can cause considerable damage to paintings because the light source generates heat and concentrate most of the light intensity on the upper part of the painting). instead, use light sources that are hung close to the ceiling.
• keep paintings away as possible from sources that can alter the air temperature or relative humidity – such as air conditioning units, heaters, coolers, humidifiers, and dehumidifiers. keeping paintings on fireplaces may be attractive, but it accelerates the deterioration of paintings, and such paintings may turn to ash too.
• even though it is convenient to alter the temperature for human comfort, it is not advisable to alter the air temperature by a considerable degree and on a frequent basis inside rooms that feature canvas paintings.

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