What is the minimum drainage time for volumetric pipettes?

The minimum drainage time for volumetric pipettes is typically set at three seconds. This time is necessary to ensure that the liquid is fully drained from the pipette tip. The design of volumetric pipettes allows for precise measurement of liquids, and adherence to the recommended drainage time is essential to maintain the accuracy and reliability of the volume being transferred. During this time, the liquid settles at the meniscus, ensuring that the correct volume is dispensed.

Options that suggest shorter drainage times, like immediate, one second, or five seconds, do not align with standard laboratory practices related to volumetric pipettes. A shorter time frame would not provide adequate assurance that the liquid has fully drained, while five seconds exceeds the typical requirement for volumetric use, potentially delaying necessary procedures without benefiting measurement accuracy.