In a post last week (and previously) I’ve mentioned the limitations of using “days away and restricted time” (DART) incidence rates as an adequate metric of an employer’s health and safety performance.  This seems especially true for refineries, chemical plants and sites with combustible dust hazards, where unitentional fires, ruptured equipment, and chemical releases may be warning signs of serious trouble.

A knowledgeable TPH reader reminded me that this very issue–the inadequacy of using DART rates to assess process safety—was addressed in the Chemical Safety Board’s report of the March 2005 BP Texas City disaster.  CSB referred to a 2004 paper by Michael Broadribb and colleagues saying:

“one key lesson for industry was that preventing major incidents ‘requires a specific focus on process safety management over and above conventional safety management,’ and ‘traditional indicators such as ‘days away from work’ do not provide a good indication of process safety performance.’”

The CSB report relies on other authoritive sources to make the point that when assessing safety and health performance of employers involved in highly-hazardous processes, employers and regulators need to consider process safety metrics, personal safety metrics, and others.  The experts noted by the CSB include Australian sociologist  Andrew Hopkins, who warns that focusing on worker injury data alone can lead lose sight of process safety warning signs, and the UK’s Trevor Klentz who lectures that personal injury rates are “not a measure of process safety.”

MSHA, OSHA’s sister agency in the Dept of Labor, recognizes that injury incident data are not sufficient, and requires mine operators to notify the agency within 15 minutes of certain non worker-injury incidents.  These include:

  • An unplanned inundation of a mine by a liquid or gas
  • An unplanned ignition or explosion of gas or dust
  • An unplanned fire in an underground mine not extinguished within 10 minutes of discovery
  • A coal or rock outburst which disrupts regular mining activity for more than one hour
  • An unstable condition at an impoundment, refuse pile, or culm bank which requires emergency action in order to prevent failure, or which causes individuals to evacuate an area.

Might there be similar non-injury incident events about which OSHA should be informed?

In my haste to write last week “Thinking beyond employer reports to focus OSHA’s attention,” I forgot to include the CSB’s assessment of this very issue—the inadequacy of relying solely on injury reports to assess worksite safety.  I appreciate the reminder from TPH reader, who I can say, does not work at the CSB.