Samples of sand from cores of modern marine sediments are so small that granulometric analyses require the use of 3 inch-diameter sieves, rather than the standard 8 inch-diameter sieves. Tests were made to determine the maximum load permissible on these sieves before the sieving efficiency is impaired. The results suggest that for a 10-minute sieving time the load should not exceed 5 finer near-mesh particles per sieve aperture. A finer near-mesh particle is one that will just pass through the aperture. A graph has been prepared showing the recommended maximum load for each sieve in the sand range. The maxima extend from 4g for a - 1 diameter sieve to 0.8 g for a 4 diameter sieve.