Class 3 – High Temperatures


The hazard controls described herein apply to all experiments that involve heating research samples to elevated temperatures and ambient pressure in a manner that may pose a significant burn or electric shock hazard. Experiments falling into this hazard class may involve the use of electric furnaces or optical furnances. Hazard controls, associated with other hazard classes, may also apply to experiments in this hazard class. The following chart illustrates how various situations may require additional hazard controls from other hazard classes:


Hazard Class

Sample decomposition from excessive heating.

Hazard Class #6 - Chemicals

Use of laser(s) to heat sample(s).

Hazard Class #4 – Lasers

Sample(s) heated due to a chemical reaction.

Hazard Class #6 - Chemicals

Associated electrical equipment Hazard Class #12 - Electrical Equipment

Experiment Category

Experiments involving previously reviewed hazard controls are categorized as low risk or medium risk experiments.

Experiments involving new equipment, processes or materials, or modified hazard control schemes are categorized as high risk experiments.

Hazard Control Plan Verification Statements

Engineered Controls – Proper grounding is needed of any conductive surfaces of the equipment in use. A GFCI may be needed to power a heating system, power supply, or other types of electrical equipment. Proper construction and connection of electrical equipment. Provide shielding if needed and use grabber-type hand tools if applicable.

Procedural Controls – Follow manufacturer's operating manual when using any commercially-manufactured equipment. Allow objects to cool before handling witout gloves or tools. Post signange "CAUTION-HOT SURFACE"

Design Reviews – Noncommercially-manufactured equipment must undergo a review by the APS before it is used on the APS beamlines. Electrical equipment associated with high temperature work must undergo a mandatory inspection of equipment by ANL Designated Electrical Equipment Inspectors. Please read the details of these inspections.

Equipment Inspections-

  • Verify proper grounding of equipment
  • Verify appropriate functioning of GFCI's before initiating the experiment.
  • Verify that the power source is adequate to provide the necessary amount of electricity to the equipment (ie, proper voltage & amperage).
  • Electrical equipment must be inspected by an Argonne Designated Electrical Equipment Inspector.

Training – Site-specific equipment orientation (provided by host Beamline).

Signs and Labeling – Systems with thermally hot surfaces that may pose a burn hazard must be posted as CAUTION: Hot Surfaces – Do Not Touch.

Personal Protective Equipment – Safety glasses with side shields, use insulated gloves intended for hot surfaces

Dosimetry and Monitoring – N/A

Experiment Authorization

Unless otherwise noted in the approved experiment safety plan, the Director of the APS Engineering Support Division delegates the authority to authorize an experiment in this hazard class to a member of the AES Experiment Safety Review Board and resident beamline personnel appearing in the Director of the AES' list of personnel having the authority to authorize experiments.

Hazard Control Verification

The Director of the APS Engineering Support Division delegates responsibility for verifying that required controls are in place to the experiment On-site Spokesperson and Beamline Management.


Reference: ESH 9.1 General Electrical Safety

Reviewed:April 15, 2013