Using a household refrigerator to store laboratory chemicals is extremely hazardous for several reasons. Many flammables solvents are still volatile at refrigerator temperatures. Refrigerator temperatures are typically higher than the flashpoint of most flammable liquids. In addition, the storage compartment of a household refrigerator contains numerous ignition sources including thermostats, light switches, and heater strips. Furthermore, the compressor and electrical circuits, located at the bottom of the unit where chemical vapors are likely to accumulate, are not sealed.
Laboratory-safe and explosion-proof refrigerators typically provide adequate protection for chemical storage in the laboratory. Laboratory-safe refrigerators, for example, are specifically designed for use with flammables since the sparking components are located on the exterior of the refrigerator. Explosion-proof refrigerators are required in areas that may contain high levels of flammable vapors (e.g., chemical storage rooms with large quantities of flammables).
Follow these rules for using refrigerators in the laboratory:
- Never store flammable chemicals in a household refrigerator.
- Do not store food or drink in a laboratory refrigerator/freezer.
- Ensure that all refrigerators are clearly labeled to indicate suitable usage.
- Laboratory-safe and explosion-proof refrigerators should be identified by a manufacturer label.
- “Not Safe for Flammable Storage" labels are should be available in each lab.
- Refrigerators used to hold food should be labeled "For Food Only".