SSE MFG. INC. - ICE CREAM PLANT - Executive Summary |
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Schwan's has historically placed a high priority on chemical safety. The corporate environmental compliance manager has been assigned overall responsibility for chemical safety in general and for ammonia refrigeration safety in particular since 1991. Schwan's maintains 3 - shift coverage of emergency responders trained to the 24-hour technician level at all facilities with ammonia refrigeration systems covered by this rule. The Marshall, MN (Ice Cream Plant) facility manufactures ice cream. Anhydrous ammonia is used in the refrigeration system at this facility. Ammonia is the most efficient and environmentally compatible refrigerant available. Although it is toxic at high concentration and is an irritating gas, it is not a cumulative metabolic poison, does not cause cancer or other dread diseases and does not cause lasting environmental damage. The refrigeration system at this facility contains about 80,000 pounds of ammonia. Schwan's calculates ammonia worst case release scenarios using the Model RMP for Ammonia Refrigeration, May 1996. All Schwan's manufacturing facilities are located in areas that meet the definition of "urban". Schwan's has chosen to calculate worst case release poundage for the largest high-pressure receiver in the system, filled to full calculated hydraulic capacity. Reduced volume for administrative controls was not used, since the described scenario would probably occur only as a result of a catastrophic vessel rupture caused by a total filling of the vessel, closure of all vessel block valves, failure of all pressure relief valves, with a simultaneous increase in liquid temperature sufficient to overpressure the vessel to the point of failure. It is the professional judgement of Schwans Environmental Health and Safety Department that a release rate of 400 lb./min. should be used as an alternate case scenario in lieu of the 100 lb./min. rate suggested in the Model RMP. The "urban" site condition will be used. Based on the above, the worst-case ammonia release scenario for the Marshall, MN (Ice Cream Plant) facility will be 33,000 pounds released over a 10-minute period. The alternate case will be a release rate of 400 pounds per minute. Both scenarios have off- site impacts. The ammonia refrigeration system is covered by the OSHA Process Safety Management (PSM) rule, 29 CFR 1910.119. The Marshall, MN (Ice Cream Plant) facility maintains a 3-shift emergency response team, trained at the 24-hour technician level. The team numbers 40 members. The training is conducted by the Vendor. The training is designed with a heavy emphasis on ammonia safety, mechanical isolation, personal protective equipment up to use of Level `A' suits and interaction with an incident command system (ICS). Copies of emergency plans are filed with the Fire Department and annual facility walkthroughs are conducted with Fire Officers. Preplanned command posts and staging areas have been designated and Inci dent Command transfer and liaison functions have been established. A post-incident debriefing is conducted after each incident. Since a continuous improvement philosophy is deeply imbedded in the Schwan's corporate culture, improvements in system safety are implemented as a result of employee-based Total Quality Management (TQM) teams, a designated PSM team and as a result of system engineering modifications and extensions. Post incident debriefings and incident investigations are used to identify additional improvements to system safety. |