1. Fatal Incident Involving a Temporary Enclosure at a Chemical Facility From an OSHA Technical Information Bulletin

2. Purpose  Provide information  Hazard alert  Requirements and regulations  Recommendations and guidance  Other information

3. Incident Description  Facility unit undergoing a turnaround.  2 workers to inspect the flange surfaces of an open 48-inch piping system.  Piping system opened to remove a piece of process equipment for cleaning.

4. Black Tarp 48” Pipe

5. Incident Description  Plastic-wrapped pipe  New moisture-sensitive catalyst upstream

6. Incident Overview N 2 Injection Reactor w/new catalyst Open 48" Piping Open Valve Closed Valve N 2 Venting Note: Actual process/piping significantly more complex. N 2 injection point 150' and several stories in elevation from pipe opening. North South

7. Incident Overview Nitrogen Purge Reactor with Catalyst Open valves to north side open piping In-Line Mixer (removed) Black Tarp

8. Incident Description  Southside open pipe & enclosure  Midday black light inspection.  Black tarps draped to block light.  Workers entered enclosure.  No problems with inspection.

9. Incident Description  North side open pipe & enclosure  Midday backlight inspection.  Black tarps draped to block light.  Workers entered enclosure.  Workers overcome upon entering.

10. Incident Conclusions  One worker died, another hospitalized.  N 2 throughout system.  Piping system was not straightforward.  OSHA cited the employer for 1910.146 Permit-Required Confined Space violations.

11. Permit Required Confined Space Hazards  Oxygen deficiency  Flammable atmosphere  Toxic atmosphere  Oxygen enrichment  Chemical exposure  Thermal hazards  Electrical shock  Temperature extremes  Engulfment  Mechanical hazards  Trapping/Pinch points  Physical hazards  Slips, Trips, Falls  Unstable working surface  Structural failure  Other recognized hazards

12. Nitrogen Hazard  Can’t be detected by human senses  N 2 displaces oxygen in enclosures (confined spaces) resulting in oxygen- deficient atmospheres

13. Human Response to Oxygen- Deficient Atmospheres Atmospheric Oxygen Concentration [%O 2 ] Possible Consequences 19.5 Meets OSHA minimum requirements for worker protection 8-10 Unconsciousness without warning; so quickly that individuals cannot help or protect themselves 6-8Fatal injury < 6 minutes 4-6Coma < 40 seconds with subsequent death

14. Requirements, Recommendations & Guidance  If space meets the definition of a PRCS, must follow 1910.146.  Even if not technically a PRCS, 1910.146 recommended.  Other OSHA standards may apply:  1910.134 – Respiratory Protection  IDLH Atmospheres  Recognition that temporary enclosures may be PRCSs.

15. Requirements, Recommendations, & Guidance  Comprehensive confined space training.  Particular attention on hazardous atmospheres

16. Related Information  OSHA Technical Information Bulletin on incident at: http://www.osha.govhttp://www.osha.gov  CSB Morten Report at: http://www.csb.gov/reports/1998/union_carbid e/98005lafr.htm  OSHA PRCS Standard, Directive and Interpretation at: http://www.osha.gov