Storage – Archives & Museums

Preservation Systems

Desiccant dehumidifier provides dry air to the required space to ensure tumidity tolerances are obtained. Desiccant dehumidifier provides preservation of the books, artwork and other organic materials that under normal environmental conditions thrive which cause irreversible damage. Other benefits of a desiccant system provide mold prevention to the dehumidified space making it more hygienic.  These systems have been implemented into the following libraries and archives around Australia:

  • Rockhampton University
  • National archives Australia Villawood
  • University Newcastle
  • Newcastle council
  • Canberra Museum
  • Katoomba Gallery


Recommendations by NLA

1. Humidity
Generally, it is recommended that relative humidity remain at 50% with a maximum change of plus or minus 5% per month.
2. Temperature
Most moulds thrive at warmer temperatures. Temperatures below freezing will not kill mould, but they do make it dormant.
For patron comfort, temperatures of 21 Celsius plus or minus 2 are acceptable in libraries, provided relative humidity is kept at 50%

Recommendations by NLA

BBC British Film Institute – Nitrate film store using Seibu Giken DST


CASE : National Archives of Australia

Desiccant Dehumidifier Upgrade
Ryan Wilks recently completed air conditioning modifications at the National Archives of Australia Chester Hill repository in the Security Vault and Low Temperature Film Vault areas.


The National Archives site provides storage of permanent Commonwealth records of enduring value and in many instances the stored records are irreplaceable. The Chester Hill site contains approximately 90% of the audio-visual records and 40% of the paper records held by the National Archives of Australia. The conditions within the building must be strictly controlled and monitored to maintain the life of the records stored within each area.

Originally the security vault and low temperature film vault were being served (dehumidified) from common desiccant units serving the film vault and inter-connecting duct and dampers.

Due to lowering of temperature within the film vault this meant that a new stand alone desiccant dehumidifier had to be installed to serve the security vault.

Whilst the change over of the two existing low temperature film vaults was relatively quite simple the work had to be planned and staged so that the conditions within the room ( 9oC +/- 1OC and 30%RH +/- 2% RH) were maintained at all times. The work, disconnect, replace, re-connect commission had to be completed in two four hour windows and involved four separate trades.

As part of our tender submission Ryan Wilks in addition to offering a
complying tender submission for the new Security Vault unit Ryan Wilks offered for consideration the supply of Seibu Giken desiccant unit. We are please to say that National Archives advised that Ryan Wilks were the only tender submission to offer an alternate option and that this innovation went a long way to securing the prestigious project.  Our alternate unit enabled the National Archives to integrate a new supplier into their system on a small scale for evaluation and to open up the marketplace and stop any monopolisation by any one supplier.

The Security vault involved the supply, install and commissioning of one new desiccant dehumidification unit to maintain conditions within the space of 20oC +/- 2OC and 50%RH +/- 5% RH). The works involved minor new ductwork to be cut into the existing security vault return air, new circuit breaker to be fitted to existing switchboards and connecting and commissioning of new BMS connects to the base building system. The works were
roughed in, in readiness for single cut over which was completed with the four hour shutdown window.

This project was another example of Ryan Wilks innovation by offering our clients an alternate option, completing critical cut over’s within tight time restraints and completing the works on time, on budget and to the satisfaction of our client.