GWWI Water Lab Analyst Practice Exam 2026 - Free Lab Analyst Practice Questions and Study Guide

A TD (To Deliver) pipet is designed to deliver a specific volume of liquid, but it does not fully empty itself at the end of the dispensing process. This is because a small amount of liquid remains in the tip of the pipet after the liquid has been delivered. The purpose of this design is to ensure accurate measurements of the liquid that has been dispensed while taking into account the liquid that remains. The residual volume left in the tip is generally accounted for in the calibration of the pipet, meaning that the user can trust the volume they are working with is precise for the intended measurements in laboratory procedures.

Opting for a TD pipet suggests precision in delivering the desired volume, but one must remember that achieving this accuracy requires acknowledging and understanding that a small quantity will be retained, which does not contribute to the final delivered measurement.