Vacuum systems pose severe implosion hazards. Follow these guidelines and requirements to ensure system safety:

• Ensure that pumps have belt guards in place during operation.
• Ensure that service cords and switches are free from defects.
• Always use a trap on vacuum lines to prevent liquids from being drawn into the pump, house vacuum line, or water drain.
• Replace and properly dispose of vacuum pump oil that is contaminated with condensate. Used pump oil must be disposed as hazardous waste.
• Place a pan under pumps to catch oil drips.
• Do not operate pumps near containers of flammable chemicals.
• Do not place pumps in an enclosed, unventilated cabinet.

IMPORTANT: All vacuum equipment is subject to possible implosion. Conduct all vacuum operations behind a table shield or in a fume hood.

CAUTION: Do not underestimate the pressure differential across the walls of glassware that can be created by a water aspirator.

The glassware used with vacuum operations must meet the following requirements:

• Only heavy-walled round-bottomed glassware should be used for vacuum operations. The only exception to this rule is glassware specifically designed for vacuum operations, such as an Erlenmeyer filtration flask.
• Wrap exposed glass with tape to prevent flying glass if an implosion occurs.
• Carefully inspect vacuum glassware before and after each use. Discard any glass that is chipped, scratched, broken, or otherwise stressed. Glass desiccators often have a slight vacuum due to contents cooling. When using desiccators, follow these guidelines:
• When possible, use molded plastic desiccators with high tensile strength.
• For glass desiccators, use a perforated metal desiccator guard.