Home-NPL | Home-TNSC
About NPL
Practices & Protocols
Climate Monitoring
Many specimens include shell or matrix material that is unstable. Most reactivity occurs with the presence of water, and thus specimens are very susceptible to high humidity.
Ideal conditions for geological collections require a relative humidity (RH) of 40-45%. Control of humidity in our small repository area (PRC122) is fairly good inside well-gasketed cabinets, but there is no climate control in the large repository (PRC33).
|
[click on image to enlarge]
Climate monitors track the fluctuations in temperature and humidity (and light levels where relevant).
This graph [red bar] shows comparative relative humidity data for the open PRC33 building and within that building the effect of being inside a wooden drawer and being inside a plastic bag inside that same drawer. Note the considerable damping effect of being inside a drawer.
Compare that with the same period of time monitored in PRC122 [blue bar], a climate controlled environment, inside a metal gasketed cabinet and within plastic in the same cabinet. This building achieved reasonable levels of control for this particular month within the tested drawers.
|
|
)