Equivalency of alternative cotton dust samplers to the vertical elutriator.

The OSHA standard for measuring cotton dust permits the use of samplers which have been demonstrated to be equivalent to the vertical elutriator (VE). The standard does not include enough criteria for the equivalency of an alternative device to be determined. Furthermore, the impact of the inherent variability of the VE on the ability to establish equivalency is not addressed in the standard. We propose a protocol which will be statistically sound and, by means of which, the equivalency of any other device to the VE may be determined. We also assess the impact of the variability of the VE on the probability of demonstrating the equivalence of another VE.