Do not attempt to extract a solution until it is cooler than the boiling point of the extractant due to the risk of overpressurization, which could cause the vessel to burst.
When a volatile solvent is used, the solution should be swirled and vented repeatedly to reduce pressure before separation.
When opening the stopcock, your hand should keep the plug firmly in place.
The stopcock should be lubricated.
Vent funnels away from ignition sources and people, preferably into a hood.
Keep volumes small to reduce the risk of overpressure and if large volumes are needed, break them up into smaller batches.
Avoid bumping (sudden boiling) since the force can break apart the apparatus and result in splashes. Bumping can be avoided by even heating, such as using a heat mantle. Also, stirring can prevent bumping. Boiling stones can be used only if the process is at atmospheric pressure.
Do not add solid items such as boiling stones to liquid that is near boiling since it may result in the liquid boiling over spontaneously.
Organic compounds should never be allowed to boil to dryness unless they are known to be free of peroxides, which can result in an explosion hazard.
Reduced pressure distillation
Do not overheat the liquid. Superheating can result in decomposition and uncontrolled reactions.
Superheating and bumping often occur at reduced pressures so it is especially important to abide by the previous point on bumping and to ensure even, controlled heating. Inserting a nitrogen bleed tube may help alleviate this issue.
Evacuate the assembly gradually to minimize bumping.
Allow the system to cool and then slowly bleed in air. Air can cause an explosion in a hot system (pure nitrogen is preferable to air for cooling).