LBNL Lessons Learned Statement

Deteriorated Nalgene Bottle Causes Acid To Leak Onto Power Strip

Background

 

A concentrated nitric acid solution leaked out of its Nalgene storage bottle and dripped onto an electrical power strip.  This strip was located underneath the elevated counter top upon which several acid containers were stored.  An electrical arc occurred when the solution contacted the energized circuit.  As a result, the countertop and neighboring electrical cords were burned before the circuit breaker tripped.

 

 

Analysis

 

Several factors contributed to this incident.  These included: the location of the power strip, the lack of secondary containment (to contain spilled and leaking liquids) and the deteriorated condition of the Nalgene storage bottle. The location of the power strip made it vulnerable to leaks and spills.  Electrical outlets need to be placed in areas where contact with liquids will not occur.  If this isn’t practical, then it is necessary to protect them with Ground Fault Circuit Interrupters (GFCIs).  The use of secondary containment, such as photo trays, most likely would have prevented this event from occurring.  As a general rule, secondary containers should be used for liquids.  The Nalgene bottles were examined.  None appeared to be leaking and all the caps were tightly screwed on.  However, one bottle had been filled to within a 1/2 inch of the top.  It was thought that internal pressure may have built up allowing the liquid to seep through the cap or through a pin hole in the side.  When hand pressure was applied to the bottle in an attempt to duplicate this condition, it shattered (see the following photograph).  According to the manufacturer, Nalgene bottles may deteriorate over time as a result of various environmental factors such as chemical degradation from the stored substance(s), temperature and exposure to ultraviolet (UV) radiation from sunlight.  (There are no UV inhibitors added to the plastic used for the containers.)  The bottle that shattered had been used for years and was yellow in color and not as pliable as a new one.

 

Corrective Actions

To prevent similar events from occurring, Laboratory personnel are encouraged to:

 

  1. Install power strips in areas free from potential liquid contact.  Also, GFCIs must be installed (and tested monthly) in areas where liquid contact is possible.
  2. Use secondary containment (photo trays) for all liquid chemicals.  These are available on-line through the VWR website: http://www.vwrsp.com/
  3. Periodically examine bottles for signs of degradation and replace them as needed.
  4. Ensure that bottles are not filled to the top.  Fill to ¾ full, leaving enough headspace for vapor build up.
  5. Store Nalgene containers away from direct sunlight.  This will minimize pressure build up from the solar load and will reduce UV degradation of the plastic.  Note:  Storage near UV germicidal lamps may hasten degradation.  Users are advised to either store plastic bottles elsewhere or inspect them more frequently.
  6. Ensure that the container is resistant to the chemical(s) being stored.  Consult a chemical resistance chart to select proper containers for the material being stored.  Nalgene is made of high density polyethylene, polycarbonate or polypropylene – each of which exhibits different chemical resistances.  The following Nalgene web site link has useful chemical resistance information: http://www.nalgenelab.nalgenunc.com/tech.html
  7. Always wear appropriate Personal Protective Equipment (PPE) when handling chemicals.  The minimum PPE required for handling chemicals in laboratories includes safety glasses with side shields and lab coats.  These should be supplemented with protective gloves as needed.  The Laboratory’s Chemical Hygiene and Safety Plan (http://www.lbl.gov/ehs/chsp/chem__hygiene.htm) has additional information on the selection and use of PPE.

 

Further Information

 

For further information please contact Carole Fried at extension 2603.