Cold Room SOP to Prevent Mold Growth


Bio Safety Update web


                                                                               Cold Room SOP to Prevent Mold Growth

Mold has been found in many cold rooms at UCSF.  Surface(s) in a cold room may become quickly contaminated with mold if improper work practices occur. Contamination with mold can result in potential health problems via inhalation of mold spores as well as contamination of research materials.  Decontamination by an outside company can be very costly.

Because many cold rooms are shared between multiple groups, a single individual can create problems affecting all users. 

Mold Cold Room 1sized               Mold Cold Room 2 sized

Preventing mold growth in cold rooms can be achieved by controlling condensation and moisture, removing materials that contribute to or promote mold growth, and decontaminating regularly.  To achieve these goals, follow these guidelines:


  1. Allocate specific storage space(s) for each laboratory. Each laboratory will then be responsible for ensuring that nothing stored within designated storage space(s) are harboring mold.
  2. DO NOT store cardboard, Styrofoam, and paper products in cold rooms.  Metal or plastic containers are allowed.
  3. Replace wood shelves with open stainless steel shelves.
  4. DO NOT store items on the floor or leave items in the sink.
  5. Label experiments in progress with name, date and responsible Principle Investigator (PI).

              Note: Unlabeled samples should be discarded by laboratory managers.

  1. Label equipment with PI name.
  2. Store unused bacterial plates ONLY. Discard if contaminated.
  3. Dispose of trash (paper towels, tubes, etc.) outside of cold room.
  4. Promptly clean up spilled liquid (e.g., buffers, media).
  5. Keep door firmly shut. 
  6. Promptly report water leaks to Facilities Management.


  • Keep surface(s) clean.  Clean cold room monthly (at a minimum).  Clean more often if necessary.
  • Document cleanings using a log sheet.
  • Wipe down plastic surfaces with freshly prepared 1:10 dilution of household bleach.
  • Wipe metal surfaces (including tops and bottoms of shelves) with 70% ethanol.
  • Sweep, mop floor, and wipe walls with freshly prepared 1:10 dilution of household bleach.
  • Clean sink with 10% bleach and rinse quickly.
  • Regularly inspect stored items for mold. If item(s) are contaminated, promptly remove/discard or otherwise decontaminate using either 70% ethanol or freshly prepared 1:10 dilution of household bleach.

                                                                                                                            Posted: Feb 2011