Fire Safety in Laboratories: Working with Hot Plates

A recent fire occurred on campus that caused substantial damage to a chemical fume hood. Many of the components of this important engineering control will have to be replaced. The cause of the fire is suspected to be due to a defect in the hot plate that was used. To continue our discussion on hot plate safety (see May 2015 Lab Rat), keep the following points in mind:

  1. Unplug hot plates when not in use. This not only reduces energy consumption, but reduces the chance of spontaneous heating events.
  2. Discontinue use of any hot plate that:
    1. Has malfunctioned
    2. Has a frayed cord
    3. Was purchased over 30 years ago
  3. When only stirring is required, use a stirrer instead of a hot plate/stirrer combo unit.

Hot plate relay heater switches can fail unexpectedly and cause spontaneous heating events. See Picture 1 for a model that has been reported to fail in this manner:

Picture 1: Corning PC-351 Hotplate/Stirrer Combo Unit

Another factor in this fire was improper storage of flammable materials. Flammable materials should be kept:

  • away from sources of heat (e.g. hot plates, heat guns & lab ovens), and
  • away from oxidizers (e.g. hydrogen peroxide & potassium permanganate)
  • away from compressed air & solvent canisters  (e.g. Dust-Off, aerosol cans)
  • covered to prevent evaporation and formation of flammable vapors.

See Picture 2 and 3 for examples of appropriate storage locations for flammable materials.


Picture 2: Refrigerator/Freezer Designed for Flammable Materials Storage


Picture 3: Flammable Materials Storage Cabinet

This entry was posted in EHSO and tagged , , , , . Bookmark the permalink. Trackbacks are closed, but you can post a comment.

Post a Comment

Your email is never published nor shared.

You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <s> <strike> <strong>