Unicom Thermal Technologies Inc. - Executive Summary

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A. Describe the Accident Release Prevention and Emergency Policies 
 
Unicom Thermal Technologies is committed to safety.  We believe all injuries can be prevented and expect all employees to assume the responsibility for working safely. 
 
Ammonia safety is a key item in our safety program.  We take many precautions to prevent or minimize accidental releases of ammonia.  These precautions include safety controls (alarms and automatic shutdown devices) which are designed to identify and prevent potentially unsafe conditions like pressure increases that could cause a system failure, a preventive maintenance program designed to maintain the on-going integrity of the system, a training program designed to ensure that the system is operated by qualified personnel, and emergency response procedures which enable trained personnel to respond quickly to system upsets. 
 
The Operations Manager is responsible for the management of the ammonia safety program. 
 
 
B.   Stationary Source and Regulated Sub 
stances Handled 
 
The Unicom Thermal Technologies Cooling Plant No. 3 is located in the lower level of the Blue Cross-Blue Shield Building in Chicago, Illinois.  The plant uses an ammonia refrigeration system to provide cold water for cooling buildings in the Loop area.  The maximum ammonia inventory at the plant is approximately 19,000 pounds.  Ammonia is the only regulated substance handled at the plant. 
 
 
C.   Summary of Worst-Case and Alternative Release Scenarios 
 
The worst-case toxic release scenario at Cooling Plant No. 3 involves the release of 3,200 pounds of ammonia to the atmosphere over 49 minutes due to the failure of an ammonia nurse tank. The release rate assumes that the enclosed engine room would limit the rate ammonia is released to the atmosphere.   Under worst-case conditions, the resulting vapor cloud could have off-site impacts. 
 
The alternative toxic release scenario at Cooling Plant No. 3 involves the release of 830 pounds of ammonia to the atmosphere over a 49 m 
inute period from a <" liquid line attached to one of the chillers. The release duration was assumed to be limited by the response of the Operators to an ammonia detector in the engine room. The release rate also assumes that the enclosed engine room would limit the rate ammonia is released to the atmosphere.  Under alternative release conditions, the resulting vapor cloud could have off-site impacts. 
 
The worst-case and alternative toxic release scenarios are unlikely for the following reasons: 
 
o The weather conditions that were used for the worst-case release scenario do not occur, while those used for the alternative case are uncommon; 
o Industry standards are followed for the design and manufacture of the equipment in the ammonia refrigeration system; 
o All ammonia equipment is located in an enclosed, sealed engine room to prevent accidents to the equipment and contain any ammonia releases that might occur; 
o Ammonia detectors should readily detect ammonia releases inside the engi 
ne room; 
o The ventilation system is equipped with a water deluge system that should remove any ammonia vapors from the air before it is exhausted to the atmosphere; 
o Pressure safety valves on the ammonia vessels should limit any pressure increases inside the vessels;  
o Ammonia is not corrosive in this service;  
o The facility has a preventive maintenance program in place to maintain the on-going integrity of the ammonia refrigeration equipment; 
o The facility has a training program designed to ensure that the systems are operated by qualified personnel; and,  
o The facility emergency response procedures that enable trained personnel to respond quickly to isolate any potential releases. 
 
 
D.   Description of the Accidental Release Prevention Program 
 
The facility has a program level 3 accident release prevention program for the ammonia system that complies with OSHA's Process Safety Management Standard and EPA's Risk Management Program Regulation.  The ammonia prevention program cons 
ists of the following elements: 
 
o Employee Participation Program 
o Process Safety Information 
o Process Hazard Analysis 
o Operating Procedures 
o Training Program 
o Contractor Safety Program 
o Pre-Startup Safety Review Procedures 
o Mechanical Integrity Program 
o Hot Work Permit Procedures 
o Management of Change Procedures 
o Incident Investigation Procedures 
o Compliance Audit Procedures 
 
 
E.   Five-Year Accident History 
 
There have not been any ammonia-related incidents at Cooling Plant No. 3 during the previous five years that resulted in significant on-site or offsite consequences. 
 
 
F.   Description of the Emergency Response Program 
 
An emergency response program has been implemented at Cooling Water Plant No. 3.  This program contains procedures describing how the facility will respond to ammonia leaks and other emergencies, including evacuation procedures.   
 
The emergency response program includes the following elements: 
 
o Pre-Emergency Planning and Coordination 
o Personnel Role 
s and Duties 
o Emergency Response Procedures 
o Evacuation Routes and Procedures 
o First Aid Procedures 
 
The program has been coordinated with the Chicago Fire Academy. 
 
 
G.   Planned Changes to Improve Safety 
 
Several items were recommended to improve the equipment and the system operating procedures when the ammonia system was analyzed in 1998.  The recommended changes have been evaluated and will be implemented as required.
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