Last Revised: April 20, 2018

An explosion caused by hydrogen gas used with an anaerobic chamber in a University of Missouri biochemistry research lab on Monday injured four people and destroyed the laboratory.  A report from Chemical & Engineering News summarizes the incident.  Four people were injured in the explosion.  One person is hospitalized.  Damages are expected to exceed $750,000.


Anaerobic chambers are used to work with oxygen sensitive organisms.  The anaerobic chambers contain various concentrations of hydrogen, carbon dioxide and nitrogen.  A catalyst system scavenges trace amounts of oxygen from the chamber.  Because the concentration of hydrogen in an anaerobic chamber may exceed the lower explosive limit of 4%, extreme care must be taken to prevent oxygen from entering the chamber.


This was not the first anaerobic chamber explosion to occur in a research lab.  Explosions have occurred due to the inadvertent admission of air into a chamber during maintenance and due to the use of a mixture of 95% hydrogen/5% nitrogen instead of 95% nitrogen and 5% hydrogen.


Explosion at University of Missouri in 2012. Photo courtesy C&EN

Lessons Learned

  • Use non-flammable mixtures of hydrogen (4%) where possible.

  • Always purchase the smallest cylinder of flammable gas needed.  Avoid purchasing full sized cylinders.

  • Verify the identity of gases before use.  It is not uncommon to received incorrect gas mixtures.

  • On start up flush chambers with nitrogen gas instead of hydrogen mixtures.

  • Leak test the chamber on start up.

  • Know how to purge the air lock on your anaerobic chamber.  Improper use of the air lock can admit oxygen into the chamber.

  • Monitor the oxygen concentration in the chamber.  Replace oxygen indicators as recommended by the manufacturer.