Ignition Source
resistively heated ceramic

A gas mixture cylinder was connected to a Fourier Transform Infrared (FTIR) Spectrometer to purge residual carbon dioxide and water vapor. A staff member was preparing to use the FTIR instrument. Prior to use of the instrument, it must be purged with dry nitrogen to remove residual carbon dioxide and water vapor. When the gas mixture reached the instrument's globar (resistively heated ceramic) heat source, a localized explosion occurred. No injuries resulted from the explosion but the spectrometer housing was heavily damaged. The internal components, including the optics and computer hardware, appeared to be in good shape.

A mixture of hydrogen and nitrogen was inadvertently connected for the purging rather than dry nitrogen. The staff member, even though an expert in the use of these instruments and quite knowledgeable of the hazards associated with the use of flammable gases, failed to recognize that he connected a cylinder of 10% nitrogen/90% hydrogen to the system rather than dry nitrogen.

Incident Date
May 18, 1983
  • Hydrogen Storage Equipment
  • Gas cylinder
  • Laboratory Equipment
  • IR spectrometer
Damage and Injuries
Probable Cause
When Incident Discovered
Lessons Learned

Procedures for safe handling of compressed gas cylinders, marking design of gas cylinders and connecting lines, and arrangement of cylinders were reviewed and modified as necessary. The spectrometer was returned to the manufacturer for a careful examination to assess the full extent of the damage. The affected laboratory area was taken out of service. Additional conspicuous markings were added to flammable gas cylinders and connecting lines. Specific training on safe handling of compressed gases was provided for all compressed gas users. The FTIR spectrometer was physically moved to a different laboratory where hydrogen cylinders were not used. All hydrogen lines and valve connections were color-coded red.