【Before the experiment】
1. Open the door and window.
2.Prepare distilled water and ice .
3. Deliver class lab reports.
4. Check safety equipment such as  fire extinguishers.

【In experiment】
1. Note that distilled water and ice are used up and replenished at any time.
2. If the floor is wet, use a mop to dry it to prevent the student from falling down.

【After the experiment】
1. Check all switches of gas, faucet, oven, rotary concentrator, water bath and cooling water machine to be closed. Pour all the washing liquid collection bottles and the measuring bottle waste into the waste container.
2. Clean the sink and clean up the lockers and garbage in the corridor lockers.
3. Clean the Hood and bench.
4. Clean the balance room
5. Sweep the floor and mop the floor in the laboratory.
6. In addition to the ventilation of the industrial area, all windows, back doors, corridors and windows of the technical road must be closed.
7. Qualified by the assistant assistant。