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1. Two test procedures sholl be published as drafts" of RILEM Recommendations: CIF-test and modified Slab test. The CIF test extends the existing RILEM Recommendation CDF test [1] which was' developed for measuring the scaling under the attack of frost and de-icing agents. The modified Slab test relies' on the Swedish Standard SS137244. 2. The tests are presented to give a basis for gaining experience. 3. The descriptions' shall be based on proposals already distributed to the Committee. 4. Responsible authors' are for CIF-Test M.J. Setzer and for Slab-Test Per-Erik Petersson and Luping Tang. 5. Two inter-laboratory-tests have been performed by RILEM TC 176-IDC in 2000 -one for CIF and one for modified Slab test, each comprising three concretes. The results have been evaluated strictly basing on ISO 5725 by Dr. Auberg and Mrs. Kasparek for CIF and by Dr. Luping Tang for modified Slab test. The results have been cross-checked by the two groups'. RILEM TC 176-IDC decided to use these precision data for the drafts,. 6. The deadline for any comments to the drafts ended Apri130, 2002. 7. The final recommendation shall be published (Helsinki 2002). 8. The internal damage is' a yes~no decision. For the internal damage found by ultrasonic trans# time in CIF test it has' been agreed upon that a damage criterion of R~=0.8 (80%) can be given where a damaged concrete can be distinguis'hed from an undamaged (R,,,, = 1.0) with sufficient statistical precision (3 *se). The test result is assessed by the number of cycles which are passed until damage criterion. II. Comments by the Chairman: 1. It must be taken into account that the results and especially the level of damage is different in both tests CIF test and modified slab test. Therefore, it is not appropriate to compare the simple number even if similar physical parameters or naming are used such as transit time, dynamic elastic modulus and relative length change. 2. Based on the inter-laboratory-test, the measured damage can be up to a factor of 3 higher in CIF than in modified Slab test. 3. The damage levels" criterion as defined herein (CIF) by the transgression below the relative dynamic modulus of O.8 marks' the value where a damaged concrete can be distinguished with su~cient statistical certain&Jkom an undamaged Therefore, it has to be distinguished from the acceptance criterion. 4. The acceptance criterion is" the number of cycles a concrete must survive before the damage criterion is passed 5. RILEM TC 176-1DC is, not prepared at this" time to propose acceptance criteria. Acceptance criteria are in the responsibility of contractors' of committees or standardization. For this, adN'tional data which link the test results with performance under practical conditions are necessary (such conditions can vary considerably based on local and regional climatic conditions).

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