Previous reports have presented full details of the treatment and installation of the test specimens in Sydney Harbour during December, 1977, and of the results of the first (6 months) inspection made during June, 1978. At the June inspection it was apparent that the plastic tubing used to make up the frames from which to suspend the specimens was inadequate for the job and not strong enough to support the heavy fouling which had occurred. Consequently, frames were re-designed and rebuilt in a heavier grade of plastic tubing and, within a week or two of the actual inspection, the remaining test specimens were transferred to new frames. These have proved entirely adequate, as can be seen from the photoqraphs. In accordance with the Working Plan (see IRG/WP/414), the whole of the remaining part of the test was re-examined on 13th December, almost exactly 12 months from the day of installation. The inspection procedure previously adopted was again followed. Fouling was assessed for whole frames as there was no apparent difference between individual groups of specimens in the amount of fouling present; the specimens were then cleaned and again assessed for teredine and crustacean attack - which were recorded separately and independently.

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