ASTM D 4557 : 1985 : R2002

1.1 This practice covers the procedures for obtaining a sample of macroinvertebrates inhabiting mud, sand, gravel, or rubble substrate.

1.2 The device is restricted to use in shallow streams or shallow areas of rivers, and it depends on a water velocity of not less than 0.05 m/s to wash the sample into a net.

1.3 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 a specific hazard statement, see 6.8.