According to the National Board of Boiler and Pressure Vessel Inspectors, boiler accidents and accidents from unfired pressure vessels are still being attributed to operator error or poor maintenance.
The report states that the total number of incidents increased by 8% (from 2,011 in 1998 to 2,163 in 1999), fatalities rose 133% (nine deaths in 1998, 21 deaths in 1999), and injuries increased 330% (from a record low of 31 in 1998 to 136 in 1999).