Resistance against marine borers: About the revision of EN 275 and the attempt for a new laboratory standard for Limnoria

Wood protection technology in the marine environment has changed over the last decades and willcontinue to do so. New active ingredients, newer formulations, and novel wood-based materialsincluding physically- and chemically-modified wood, together with increasing concerns overenvironmental impacts of wood preservatives, urgently demand a major revision of EN 275 "Woodpreservatives - Determination of the Protective Effectiveness against Marine Borers", dated from1992. This IRG document reports on the technical work in CEN TC 38 regarding the revision ofthis standard. A Task Group within WG 24 of CEN TC 38 was formed consisting of experts fromdifferent field of competence (e.g. wood preservatives industry, wood scientists, marine biologists,archaeologists and cultural heritage conservators). Starting by e-mail correspondence in 2014, andcontinuing with four physical meetings (Berlin 2x, Florence, Venice) with experts from Germany,Italy, Sweden, and UK were held so far. Significant items for revision in EN 275 were identifiedas: number of replicates, duration of the test, dimension of specimens, number of test sites, numberof reference species, reference material including reference preservative, re-immersion ofspecimens after non-destructive periodical evaluation for longer periods of time vs higher numberof replicates for successive destructive examinations without re-immersion, utilization of X- rayapparatus and specific software to ease evaluation, etc.Furthermore, the task group is working on a standardized lab test for time-saving evaluation ofdifferent wood qualities for their potential to resist attack by limnorids. The suitability of this labtest will be determined by round robin tests as soon as safe face-to-face collaboration permits. Theoutcome will be published as a CEN TR (Technical Report) document, with a view to eventualadoption within the revised standard.