How to properly use a fume hood in the laboratory

When the test operation is carried out in the laboratory, various harmful gases, odors, moisture and flammable, explosive and corrosive substances may be produced. In order to protect the safety of the operator and prevent the spread of contaminants from the test to the laboratory, fume hoods are used in close proximity to the source of contamination.

1. Introduction to fume hood

The fume hood is one of the most commonly used local exhaust devices in the laboratory. Its main function is to release all kinds of toxic and harmful gases in the fume hood. There are many kinds of fume hoods, different structures, and the fume hoods used in the laboratory at present mainly have five types: natural ventilation fume hood, slit fume hood, top pumping fume hood, bypass fume hood and supplemental air fume hood.

2. Use and maintenance of fume hood

The quality of the use effect of the fume hood is not only related to the design and installation, but also has a great relationship with the reasonable use and maintenance. When using and maintaining the fume hood, the following points should be noted:

1) Before the start of the test, the test operation can only be carried out if the fume hood is confirmed to be in operating condition.

2) After the end of the test, it should continue to run for at least 5min before turning off the ventilator to discharge the residual gas in the pipeline. Consideration may also be given to installing an exhaust time delay to ensure delayed operation of the ventilator.

3) During the test, do not put any equipment within 150mm from the glass window, and the large test equipment should have sufficient space, which should not affect the flow of air, and the front window should be closed as much as possible.

4) The test device that produces harmful substances should be placed 150mm away from the operation port to prevent the overflow of harmful substances.

5) The test device in the fume hood should not block the exhaust slit.

6) The inside of the fume hood should be kept clean and closed frequently, and it should be cleaned regularly.

7) In order to make the glass door slide flexibly, lubricating oil should be added to the pulley regularly.

8) Ventilators, air ducts and related accessories should be regularly overhauled.