1. Development of a single test procedure to assess performance of preservatives against soft rot fungi is an ideal that cannot be realised at present, if results are to be both reproducible between laboratories and pertinent to the practical requirements of individual countries. 2. Consensus opinion amongst members of Sub Group I - Soft rot tests, of Working Group II - Fundamentals of Testing, of the IRG, is that the immediate needs of CEN would be best answered by: (a) a code of recommended practice, (b) a multiplicity of test procedures, and (c) a degree of flexibility in test procedures. 3. The code of recommended practice should recognise the need for: (a) a pure culture, synthetic medium (sand or vermiculite + nutrients), single wood species test to be adopted by all laboratories as a common reference point of testing, (b) mixed inoculum and/or unsterile soil laboratory or fungus cellar tests which account for local variations in the fungal flora, (c) incorporation of a range of wood species where applicable (i.e. where mixed hardwoods comprise the main resource), (d) provision of local internal standards of known performance under field conditions, (e) incorporation of leaching procedures other than standard methods with deionized water (e.g. mild acid, milk alkali, ionic solutions of various salts) where applicable to local exposure conditions, (f) precise definition of the criteria used for establishing toxic thresholds (mass loss, strength loss, microscopic examination). 4. Initial screening tests should remain the province of the individual research worker. 5. The code of recommended practice should have the sole purpose of establishing provisional retention levels for subsequent confirmation by field trial. 6. IRG should list and approve test procedures considered adequate to establish toxic thresholds for preservatives against soft rot fungi. 7. It should be clearly understood that when using a series of test techniques, it is inevitable that a range of toxic thresholds will be obtained for the same preservative. 8. Guidelines should be drawn up for interpretation of test data for subsequent transformation to provisional retention levels. 9. Adoption of the broad principles outlines above is recognition of the dynamic nature of toxic thresholds. The additional information obtained by a more flexible, and complex, approach to testing may make interpretation more difficult but should provide data from which response of preservatives to varying biological and environmental hazards can be more realistically assessed. 10. It is recommended that CEN adopt, in principle, the basic philosophy of testing outlined above and move towards formulation of a Working Document in collaboration with IRG

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