1.1 This practice covers the procedures for obtaining a qualitative sample of macroinvertebrates inhabiting sand, gravel, mud, clay, and similar substrates.

1.2 This grab sampler has limited application, and is not recommended for quantitative benthic work.

1.3 The grab must be used with due consideration of its defects when quantitative estimates are attempted.

1.4 This device is used primarily in freshwater lakes and reservoirs and is adaptable to river, estuarine, and ocean habitats.

1.5 For the advantages and disadvantages, see Guide D 4387.

1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. For specific hazards, see Section 5.