NCS is pleased to report that we will soon be able to offer a materials and products test as a modern alternative to the old Oddy test that has served the sector so well for 45 years. Working with Dr George Tranter of ChiraLabs Ltd at the Oxford University Science Park, Begbrooke, we have reviewed the approach used by the British Museum and others. Dr Tranter has developed a new, more rigorous analysis of the effects of product samples on silver, copper, iron and other coupons, at 55% RH and at 22 degrees C. Results from the new approach of exposing and analysing the surfaces of the coupons can be identified within a week to a fortnight. Our first phase in introducing the test was a series of trials, carried out in the last year, on common 'archival quality' and non archival quality materials (papers, tissues, textiles, paint, plastics etc). Perhaps the most important feature of the new approach to anaylising changes is that almost every material has been seen to have an effect on the coupons regardless of its popular notion of being stable or 'archival'. Materials either change the surface characteristics in the manner of tarnishing/corrosion, as used visually in the Oddy test, or coat the surface of the coupon. In acknowledgement of the fact that it appears few if any materials do NOT have some effect on a substitute for heritage (the coupon), we have set out a slightly different approach to evaluating the effects. Instead of a Pass, Fail or Temporary Use 'scoring', as used by the British Museum for example, we aim to use High Risk, Medium Risk and Low Risk categories for the results, with some suggested interpretation of what these risk values represent in terms of change to a heritage item over time. We aim to offer a service to test potential materials that institutions wish to use, for building-related reasons (wall paints, coatings, floor coverings etc.) and for exhibition, storage and conservation such as fabrics, boxboard, conservation treatment materials and adhesives, mount materials, inks etc. We will also do tests for product suppliers wishing to have their products evaluated for heritage sector uses. The service will be charged for at a low cost. There will be options such as a silver only test, or one using three coupons, and we expect that specialist alternative coupon tests will also be available on request. We will report results of tests and set up a form of quality marking for suppliers' products, which will have time limits to ensure that new batches of a product are tested periodically in order to retain the mark, since manufacturing methods and sources of raw materials and components change over time. With the initial sample trials over, to start to roll out this new testing service we would like to offer to carry out tests for any institution or supplier at cost for a period of approximately 3 months: £80 or 90Euros for the silver test, £175 or 195Euros for the 3 coupon test, plus VAT where applicable. Part of this second trial period, for logistics, will involve the mechanism for requesting a test, getting the product/material to us, and handling several samples at one time, as well as getting feedback on the form of test report and evaluation information. We expect to be putting details and a means of requesting tests on our website in the coming month. A full academic report setting out the methodology for the testing process will be published in suitable peer-reviewed science and conservation journals. If you are interested in the test and the service, please would you email us at [email protected][1] We would, for example, welcome a public discussion about what constitutes High, Medium or Low Risk to heritage when carrying out a proxy test in a laboratory. The National Conservation Service is a registered non-profit membership organisation for archives, libraries and museums without conservation staff. _____________________________________________________________
Chris Woods PGDipCons BAhons CertCons RMARA ACR FIIC Director National Conservation Service 21 Albemarle Street Mayfair London W1S 4BS www.ncs.org.uk tel: 00447495949170 NCS membership is operated by Nationwide Conservation Service Ltd, a not-for-profit membership company limited by guarantee, registered in England & Wales no. 07077608, VAT reg. 202361951. NCS projects are provided by a network of independent Associate practices and by Conservation Ltd, a company registered in England & Wales no. 6659286 VAT reg. 981696269. Both companies are registered at 21 Albemarle St, Mayfair, London W1S 4BS Links: 1. mailto:[email protected] ****** Unsubscribe by sending a message to [email protected] Searchable archives: http://cool.conservation-us.org/byform/mailing-lists/cdl/
