Refrigerator Safety Requirements in Lab Areas

May 2016
Lesson Learned Statement: 
During recent laboratory safety inspections, several issues were observed regarding refrigerator and freezer use in laboratories. Flammable materials were found in refrigerators/freezers that were not designed for flammable storage. In addition, these refrigerators/freezers were not labeled to clearly indicate that flammable materials were not allowed. Refrigerators/freezers are commonly used laboratory equipment. Selecting the proper refrigerator/freezer is an important consideration not only for maintaining the integrity of research materials but also for safety. 
Refrigerators/freezers in technical areas must be labeled as to their purpose with regard to chemical storage as follows:

-- Refrigerators/freezers used for storing flammable and combustible liquids must be designed for that purpose and have labeling that identifies it as such. This is typically a manufacturer's label.
-- Standard refrigerators/freezers located in technical areas must have a "Warning -- No flammable material storage" label.
-- All types of refrigerators/freezers in technical areas must have a "No food and drink" label. 
-- Labels are available by contacting your Health and Safety Representative. See PDF attachment at the end of this Lessons Learned for examples of these labels.

There are generally three types of refrigerators/freezers:
1) Standard refrigerators/freezers. These include ordinary domestic refrigerators/freezers and laboratory refrigerators/freezers that are not designed or approved for storage of flammable materials;
2) Flammable materials storage refrigerators/freezers; and
3) Explosion-proof refrigerators/freezers.

Standard refrigerators/freezers contain electrical components that are potential ignition sources, which may initiate a fire or an explosion if flammable vapors are present. Flammable material storage refrigerators/freezers are designed to isolate ignition sources from flammable vapors inside the unit. Explosion-proof refrigerators/freezers are designed to isolate ignition sources from flammable vapors inside AND outside the unit. Explosion-proof refrigerators/freezers would only be required in areas expected to experience concentrations of flammable gases and/or vapors at or above their lower flammability limits for extended periods of time. This scenario is unlikely to occur in laboratory spaces at LBNL.

Additional general guidance to use your refrigerator/freezer safely includes:

  1. Do not overload your refrigerator/freezer.
  2. Understand the storage requirements for each chemical or sample before placing it in a refrigerator/freezer. Refer to the Safety Data Sheet (SDS) for your chemicals for more information.
  3. Store liquid containers in an upright position and use secondary containment trays for hazardous liquids. 
  4. Segregate incompatible materials.
  5. Follow the manufacturer's guidance for operation and maintenance of refrigerators/freezers.
  6. Include considerations regarding emergency power needs for your refrigerator/freezer in the event of a power outage.
  7. Refrigerators/freezers must be plugged directly into the wall outlet. Use of extension cords and power strips for refrigerators/freezers is an electrical hazard and is prohibited. A recent Lessons Learned (LL16-0020) addressed this topic.
Please contact the following subject matter experts if you have any questions regarding this briefing.