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Risk Management Bulletin


By July 1, 2010No Comments

There are nearly 5 million permit-required confined spaces in workplaces nationwide, plus another million “non-permit” spaces. Confined space accidents, which often result in injuries or fatalities, happen more often than you might think. According to the National Institute of Occupational Safety and Health, these mishaps usually occur because workers encounter one or more of these potential hazards:

  • Lack of natural ventilation
  • Oxygen-deficient atmosphere
  • Flammable/explosive atmosphere
  • Unexpected release of hazardous energy
  • Limited entry and exit
  • Dangerous concentrations of air contaminants
  • Physical barriers or limitations to movement
  • Instability of stored products.

To prevent, or minimize accidents in confined spaces, we’d recommend a three-pronged safety program: Training, testing, and rescue preparedness.

1. Train
Training should emphasize recognizing what constitutes confined spaces, the potential hazards they pose, and the precautions that workers and managers must take to prevent accidents and injuries. Stressing that death is a likely outcome in confined space accidents usually makes trainees sit up and take notice.

2. Test
Testing, evaluation, and continuous monitoring are essential. More than half of confined space fatalities result from hazardous atmospheric conditions such as toxic vapors or lack of oxygen. NIOSH recommends that a qualified person test all confined spaces for oxygen level, flammability, and known or suspected toxic substances to determine whether the atmosphere is safe for entry.

3. Rescue
Make sure that trained, equipped, and experienced rescue personnel are available in case of emergency. A significant percentage of confined space fatalities and injuries involve would-be rescuers who rush in without proper training or equipment. NIOSH advises creating rescue procedures specific to the type of confined space and its hazards before rescuers enter the space.