Confined spaces may include, but are not limited to:

  • Vessels, tanks, towers, vessels skirts, tank cars, bag houses, pipes, and ventilation and exhaust ducts, silos and vats.
  • Equipment under construction or fabrication or in demolition with limited openings for entry or with the potential danger of engulfment.
  • Newly created confined spaces during maintenance and servicing activities (for example: welding enclosures for hot work activities).
  • Boilers and furnaces.
  • Dikes, pits, trenches (i.e. rainwater or wash water) and excavations with restricted access that are more than 1.2 meters (4 ft) deep or less than 1.2 meters (4 ft) deep but with the potential danger of solid, liquid, or vapor engulfment.
  • Trenches, dikes and cooling tower basins that could contain, hold or produce dangerous air contaminants or oxygen deficient atmosphere.