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Narration : 1. Laboratory Hood

• During chemical experiments, harmful gases or dust particles may be released, and volatile organic solvents are often handled.
• The hood is used to protect you from inhalation of harmful gases or vapor.
• Let's check airflow and the working of the hood with the help of dry ice smoke.
• When the equipment is switched off, the vapor will leak outside.
• When switched on, the fan outdoors starts moving and the air inside the hood will be sucked out.
• Then, the vapor will not leak out.
• If the front door of the hood is opened wide then it will not function to full capacity.
• So during an experiment open the door to a bare minimum.
• You should never put your face inside the hood, or you will inhale harmful gases or vapor.
• While using the hood, open the door to a bare minimum just enough to operate the apparatuses inside.
• This is exhaust equipment on the normal lab bench.
• When switched on the air will be sucked out.
• If the shutter is closed, the air will not be sucked out.
• Hence, it is important to open the slit.