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8.1 Explosives

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Under the OSHA Laboratory Standard and the Globally Harmonized System (GHS), explosive chemicals include substances or mixtures that can rapidly release gas, heat, and pressure due to shock, friction, impact, heat, or contamination. For transportation purposes, the Department of Transportation (DOT) classifies explosives as Hazard Class 1.

Although most laboratories do not routinely work with primary explosives, a number of laboratory chemicals can become shock-, friction-, or heat-sensitive over time due to aging, drying, contamination, or peroxide formation. These materials can pose serious risks even when stored in closed containers.

If you discover a chemical container that appears unstable, crystallized, dried, corroded, swollen, or otherwise suspicious, do not touch or move it.

For emergencies or suspected unstable/shock-sensitive materials:
Call 911 from any Cornell University landline, or 607-255-1111 from a mobile phone.
Cornell Public Safety Dispatch will immediately contact EHS.

Explosive or potentially explosive materials can cause significant damage to equipment, ventilation systems, glassware, and building structures, and may generate toxic byproducts. Before performing any experiment with an explosion risk, determine whether a safer substitute is available. If the use of an explosive or potentially explosive material is necessary, you must obtain prior approval from your Principal Investigator and review all relevant safety information (e.g., SDS, technical literature, and EHS guidance).

For non-urgent questions regarding explosive or potentially explosive chemicals:
Contact EHS at askEHS@cornell.edu .

When preparing or conducting experiments involving potentially explosive materials:

  • Use the smallest feasible quantity of material.
  • Conduct work behind an appropriate blast shield and within an area that provides adequate protection. Some energetic reactions may require a designated workspace outside the fume hood; consult EHS for guidance.
  • Remove unnecessary equipment and incompatible chemicals (especially flammables and toxics) from the immediate work area.
  • Notify laboratory personnel of the planned work, hazards involved, and anticipated timing.
  • Use spark-resistant, non-metallic tools when manipulating sensitive materials; avoid scraping or friction.
  • Ensure temperature-control, pressure-relief, and quench systems are in place when required by the procedure.
  • Dispose of waste promptly through EHS and clearly indicate if the waste contains any potentially explosive constituents.
  • Wear appropriate PPE, including gloves compatible with the chemical hazard, a lab coat or apron, chemical splash goggles, and a face shield or blast shield when required.

Storage: Date all chemical containers when received and when opened. Certain compounds must remain wetted to remain stable (e.g., picric acid, 2,4-dinitrophenylhydrazine). Never attempt to open or move a container that appears to show signs of aging or instability, including:

  • Deterioration or corrosion of the container
  • Crystalline deposits in or around the cap or threads
  • Discoloration of the solid or liquid contents

If any of these conditions are observed, stop immediately and call Cornell Public Safety Dispatch at 911 from a Cornell landline or 607-255-1111 from a mobile phone.

Examples of explosive or potentially explosive chemicals include:

  • Chemicals containing azide, diazo, nitroso, acetylide, haloamine, peroxide, or ozonide functional groups
  • Nitrocellulose (especially when dry or aged)
  • Di- and tri-nitro aromatic compounds
  • Peroxide-forming compounds
  • Picric acid (dry)
  • 2,4-Dinitrophenylhydrazine (dry)
  • Benzoyl peroxide (dry or contaminated)
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