Lab Training Videos

Using a Micropipette

This video will cover the correct way to use a micropipette. A micropipette is an instrument that is used in the lab to measure and transfer very small quantities of liquid. When the control button is pressed, a piston in the pipette moves in that direction. When the control button and piston are allowed to move upwards, liquid can be aspirated into an attached pipette tip. With a downward movement of the piston, liquid can be dispensed. The proper operation and maintenance of the micropipette is fundamental to solution and sample preparation, and is critical to accurate and reproducible measurements in the laboratory.

Micropipette: Common Mistakes

This video will cover the most common mistakes that could be made while using a micropipette. There are many ways that a micropipette can be misused in the laboratory, from dropping the micropipette to using it with acid. These mistakes can affect the calibration of the micropipette, causing it to be inaccurate. All laboratory users will benefit from making sure that everyone uses the pipettes correctly, because the pipettes are a communal resource. Pipette inaccuracy will affect everyone’s work. Because of this, if you see someone using the pipettes incorrectly, let them know. The laboratory manager can also be notified if the problem persists.

Pipette Calibration and Proficiency Test

The only way to ensure accurate and precise solution delivery is by regularly checking each pipette on the analytical balance. High quality and consistent results depend on a skilled operator properly using well maintained equipment. This video will cover the procedure for calibrating a micropipette, as well as the proficiency test used to determine if the user is pipetting correctly. Calibration of a micropipette officially means determining the difference between the dispensed volume and the selected volume. This can tested by weighing the volume of distilled deionized water pipetted onto a sufficiently sensitive analytical balance. New users will be asked to perform pipette calibration as a proficiency test in order to demonstrate that they are able to use a micropipette correctly, and with sufficient accuracy. If needed, review video on proper use of the analytical balance before proceeding.

Using an Analytical Balance

This video will cover the correct way to use an analytical balance. The analytical balances, located in room 203 are the most important measuring devices in the laboratory. They should be used to prepare accurately weigh out chemicals for reference and calibration standards. Each balance must only be used for its designated purpose. 

Analytical Balance: Common Mistakes

This video will cover the most common mistakes that could be made while weighing with an analytical balance. Proper use of each balance is critical to ensuring accurate results in the laboratory. Never move a balance unless it is absolutely necessary, and only after obtaining permission. If a balance is moved, it could be damaged and will certainly be un-leveled. Balances not properly cleaned of debris or spilled substances after use will not weigh accurately.

Calibrating and Leveling a Balance

This video will cover how to calibrate and level all the analytical balances present in the lab. All WSL balances are serviced and checked annually by a professional balance service. Between these service visits, it is up to the staff and students using the equipment to ensure that each balance is properly used and maintained. Remember each balance has a specific range and appropriate use.

Glass Bottle Combustion

This video will cover the combustion of certain glass bottles. Some glassware is heated for final cleaning. All glass bottles used for trace organics and dissolved organic carbon determinations must be combusted to destroy any remaining contaminants from container walls.


This video will cover the general types of glassware and how each is used and reused. Clean glassware, and labware in general, is incredibly important to the proper functioning of the laboratory.

Difficult or unusual glassware

This video will cover the cleaning of volumetric glassware. Volumetric glassware, as a general rule, is only used for preparing standards and transferring solutions to a glass or polyethylene bottle for storage.

General cleaning

This video will cover general cleaning of all labware. This is the first step of the cleaning process.

Common mistakes

This video will cover the most common mistakes that could be made while cleaning labware.

Acid rinsing

This video will cover the process of acid rinsing. Acid rinsing is another step in the cleaning process, but applies only to certain glassware and sample containers.