Presentation and question about calculators long term storage at low temperature

[Giancarlo]

Hello,
As a conservation specialist in my daily job (for ancient artifacts) i use to store my calculators in almost sealed boxes with moisture absorbing materials like silica gel or others. Relative humidity and its variation over time is our enemy. With silica gels we are able to stabilize relative humidity. Normally (it depends on artifacts history) organic materials are well preserved with a rh around 50-55%
Metals need lower values of relative humidity like <40%. I am not a specialist in electronic components preservation value but i would assume that these components are impacted by oxidation supported by the presence of water vapor in the air.

Normally temperature is not important by itself, 99,999% of the artifacts are not subjected to temperature control. Temperature variations are dangerous because they are responsible of relative humidity variation so it has an indirect impact.

In modern artifacts what concerns me a lot is emissivity of materials like plastics or electronic components (the so called outgassing). For these materials there are some activated charcoals that could help to absorb these pollutants and replace them from time to time.

If someone is interested on this subject i may detail with other useful information like display cases air tightness and active devices to control relative humidity.

Thanks

Giancarlo