SSE MFG., INC. - CONVENIENCE FOODS - 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 (Convenience Foods) facility manufactures frozen  
convenience foods. 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 15,000 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 condit 
ion will be used. 
 
Based on the above, the worst-case ammonia release scenario for  
the Marshall, MN (Convenience Foods) facility will be 14,000  
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 (Convenience Foods) 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  
bee 
n designated and Incident 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.
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