It is critical for archive environments to maintain adequate environmental levels in areas where historical records are held. An unsuitable environment, including inappropriate temperature and humidity levels, can adversely impact the condition of precious materials, causing issues such as mould growth and accelerating the rate of material deterioration.
Berkshire Record Office holds the archives of
the Royal County of Berkshire. It exists to look after
nearly 900 years of the County's history,
including that of its major towns such as Reading, Newbury and
Windsor. Records under its care include those of public
authorities, e.g. councils, hospitals and courts, and also of
businesses and individuals.
Sue Hourigan, Senior Conservator for Berkshire
Record Office, helped to design the current, purpose-built building
in which the Berkshire Record Office runs its services and stores
its archives. Responsible for looking after 7 miles of historic
records across six strongrooms, Sue is experienced in
maintaining the correct environment for effective
To ensure that suitable levels of temperature and humidity are
maintained in the Record Office's six strongrooms, Sue uses
Tinytag Ultra 2 TGU-4500 indoor temperature
and relative humidity data loggers.
In each of the strongrooms, a Tinytag data logger
continuously monitors and records the temperature and
humidity levels. Data is downloaded to a PC from the data
loggers at least twice a month using Tinytag Explorer software. Sue
is particularly pleased with the flexibility of the software's
graph customisation features that allow her to adjust how the data
is visually presented: "I adjust the graphs to
represent water and heat - so, the relative humidity line is blue,
and the temperature line is red," she explains.
It is essential for the Record Office to understand daily
temperature and relative humidity levels. Mould
growth, which happens at a higher humidity, is a
particular concern for archive environments; it can cause
irreversible physical and chemical damage to many
of the irreplaceable items in archival collections and presents a
significant health hazard to those who handle affected items. Data
from the loggers helps Berkshire Record Office to keep temperature
and humidity at the correct levels to prevent such damage to their
collections. If the data shows higher humidity than is ideal, Sue
is able to ensure that the air conditioning is adjusted in
Data from long-term monitoring is also
important for helping the Record Office to maintain the archive
environment and achieve its aims. Long-term environmental data
supported the Record Office's application for Archive
Service Accreditation, which it achieved in 2017. The data
from the Tinytags showed that the strongrooms were kept within the
correct environmental parameters for the required number of days,
allowing the Record Office to prove that the archive environment is
suitable for effective preservation of the collections.
The Tinytag Ultra 2 data loggers and easy-to-use
Tinytag Explorer software have been invaluable
for Berkshire Record Office's collections care. Reflecting on her
experience using the loggers, Sue comments, "I wish I
had bought the Tinytags sooner!"
Images courtesy of The Berkshire Record Office.