Centeon L.L.C. - Executive Summary

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1.1    SOURCE 
The Centeon L.L.C., Bradley, Illinois, pharmaceutical manufacturing  
facility is subject to the United Stated Environmental Protection Agency's  
(USEPA's) Risk Management Program (RMP) for Accidental Chemical Release  
regulation (40 Code of Federal Regulations [CFR] 68) because it has a  
refrigeration system that contains more than the threshold quantity (10,000  
pounds) of anhydrous ammonia (ammonia) (Chemical Abstract System  
[CAS] Number 7664-41-7).  Anhydrous ammonia (NH3) is a gas at ambient  
conditions.  The ammonia refrigeration system is used to control the  
processing and room temperature for plasma-derived and related  
products.  It is a closed system that contains approximately 80,000 pounds  
(i.e., 15,123 gallons) of ammonia in various physical states (gas, liquid, and  
saturated vapor).  The vessels, which can contain the largest volume of  
ammonia, are the dual high-pressure (HP) receivers.  The HP receivers are  
considered o 
ne vessel since they are interconnected and equalized such  
that liquid and vapor is equally distributed between them.  The vessels  
operate at approximately 150 to 180 pounds per square inch gauge (psig)  
and can contain as much as 29,624 pounds of liquid ammonia.  However,  
during typical operation, the vessel holds only about 10,000 pounds.  Most  
of the ammonia equipment is located indoors.  The HP receivers,  
condensing towers, some chillers, and most piping runs are located  
Ammonia is the oldest and most common refrigerant in general industrial  
use throughout the world.  It is a high capacity refrigerant that operates at  
reasonable pressure.  At this facility, personnel exposure to more than a  
small leak is rare because ammonia operates within a closed system of  
vessels, piping, and equipment and its self-alarming properties allow for  
immediate detection and response. 
Centeon's ammonia refrigeration system is a two-stage system consisting 
of a high pressure (HP) side and a low pressure side.  The Building No. 4  
chillers operate on the low side (i.e., low pressure) to quickly chill alcohol  
or cool room air.  Ammonia suction from the Building No. 4 equipment at  
about -10 psig passes through the low side accumulator before entering  
the low-back compressors.  Liquid ammonia in the low side suction is  
trapped in the low side accumulator and returned to the high side  
accumulator.  The booster compressor discharge is desuperheated in the  
high side accumulator before entering the high side compressors. 
The high side compressor suction draws from the high side suction  
accumulator at about 20 psig.  This accumulator receives suction from  
various chiller units.  Excess ammonia liquid that collects in the high side  
accumulator is removed and returned to the system. 
The major discharge from the high side compressors (hot gas), at 150 to  
175 psig, is vented to four condensing towers. 
The condensed liquid is returned to 
the HP receivers where it is fed to the  
low and high side equipment, including the chillers and room coolers. 
The ammonia refrigeration system is well protected by the existence of  
specific safety systems and hardware, including safety relief valves,  
engine room ventilation, and system safety interlocks.  Safety relief valves  
protect the HP receivers, compressor discharge, condensers, suction  
accumulators, oil pots, and pump-out system from the hazards associated  
with overpressure.  Safety interlocks include HP and high temperature  
alarms and cutouts for the compressors, as well as high level floats and  
sensors for vessels. 
Centeon's refrigeration system is a totally closed system.  Historically,  
releases of ammonia from industrial refrigeration systems most often  
occur from leaking valves, malfunctioning pressure relief devices, or  
inadvertent releases during repair activities.  While these incidents can  
impact employees, this facility ha 
s never experienced a release of a  
reportable quantity that represented an off-site impact (i.e., beyond the  
property line). 
Consistent with the RMP rule requirements, two specifically defined  
release scenarios (a worst-case release and an alternative release) were  
analyzed to determine the maximum distance to an endpoint where the  
ammonia concentration is 200 parts per million in air, or 0.02 percent.  This  
endpoint represents the maximum airborne concentration below which  
nearly all individuals could be exposed for up to 1 hour without  
experiencing or developing irreversible effects or symptoms that could  
affect their ability to take protective action. 
The release scenarios analyzed are based upon the guidance contained in  
the USEPA's Risk Management Program Guidance for Ammonia Refrigeration  
(the "Model Plan"), dated November 1998.  This guidance document used  
the SACRUNCH atmospheric dispersion model to construct "lookup"  
tables that relate the quantity and rate of a 
mmonia released to the  
endpoint distance. 
The worst-case release is considered to be defined (according to the RMP  
Rule) by the catastrophic rupture and complete loss of the maximum  
contents of the HP receivers (approximately 29,624 pounds of ammonia)  
over a 10-minute period.  Using the specified worst-case meteorology  
contained in the Model Plan, the distance to the endpoint for a worst-case  
release was estimated to be 10,507 feet or 1.99 miles. 
Although the worst-case consequence analysis is required by the RMP, it  
should be considered a highly unlikely event.  Design, construction, and  
operation of the HP receivers is such that worst-case failure is extremely  
remote.  The receivers were designed and constructed in accordance with  
the American Society of Mechanical Engineers (ASME) Boiler and Pressure  
Vessel Code (Section VIII), and were certified and stamped by the National  
Board of Pressure Vessel Inspectors (National Board).  Third party and  

tate mandated inspections of the vessels' condition occur every year by a  
Factory Mutual inspector who has been certified by the National Board.   
In addition, the vessel is inspected daily by plant motive power personnel  
trained in the operation of the system. 
There are only two potential causes for a worst-case scenario involving an  
HP receiver:  (1) the internal pressure to increases uncontrollably and  
ruptures the vessel from the inside; or (2) rupture of the vessel wall occurs  
due to inadvertent contact (e.g., vehicular) from the outside. 
The vessels at Centeon are operated well below the design pressure (i.e.,  
maximum allowable working pressure) of 250 psig and because of the  
safety factors built into the ASME Code, a fourfold pressure excursion, to  
approximately 1,000 psig, would have to occur before a worst-case vessel  
failure.  Such pressures could not be generated internally.  The only logical  
external cause of HP would be flame impingement or surface heat from a  
high challenge fire adjacent to the vessels.  If this were to occur, the vessels  
are equipped with safety relief valves (SRVs) set to relieve internal  
pressure at 250 psig.  A HP excursion would not occur as long as the SRVs  
continued to function.  Actuation of the SRVs would result in an ammonia  
release similar to that described in Section 2.2 for the alternative-release  
scenario.  The SRVs are on a 5-year replacement schedule, in compliance  
with the International Institute of Ammonia Refrigeration (IIAR) guidance  
contained in IIAR Bulletin Number 109, Minimum Safety Criteria for a Safe  
Ammonia Refrigeration System, in an effort to ensure that they will function  
properly when required. 
Furthermore, inadvertent vehicular contact with the vessel is unlikely  
since the unit is protected with substantial barrier protection designed to  
preclude this occurrence.  (The vessels are located beneath the evaporative  
The worst-case release scenario is unlikely for the  
following additional  
 The worst-case weather conditions which were used for this scenario  
are uncommon; 
 Typically, the receiver contains only 10,000 pounds of ammonia; 
 Industry standards were followed for the manufacture and quality  
control of these receivers; 
 Ammonia is not corrosive in this service and the vessels are less than  
15 years old; 
 Safety relief valves limit operating pressures in these receivers; 
 The facility has a preventive maintenance program in place designed  
to maintain the ongoing integrity of the vessels; 
 The facility has a training program designed to ensure that the system  
is operated by qualified personnel; 
 The facility has emergency response procedures designed to enable  
trained personnel to respond quickly to isolate any potential releases; 
 Main ammonia shut-off valves exist that are designed to allow  
personnel to stop the flow of ammonia quickly in an emergency; 
The alternative,  
or scenario is considered to be defined (according to the  
Model Plan) by a release of ammonia through a one-quarter-inch effective  
diameter hole in a high side (i.e., 150 psig) pipe or vessel, releasing  
118 pounds of ammonia per minute for up to 60 minutes.  This release is  
representative of a small pipe or vessel leak.  Because the HP receivers and  
some piping are located outdoors, passive (building) mitigation  was not  
used to reduce the release rate or the distance to the endpoint.  Active  
mitigation  was considered, because it is believed that emergency  
responders could identify and stop the leak in less than 60 minutes.   
However, a rapid response does not change the TEP distance obtained  
from the Model Plan. 
Using the specified meteorology contained in the Model Plan, the distance  
to the endpoint for the "more likely" release scenario was estimated to be  
450 feet or 0.1 miles. 
As with the worst-case scenario, the alternative-release scenario is unlikely  
for the  
following reasons: 
 Industrial standards were followed for the manufacture and quality  
control of these lines; 
 Ammonia is not corrosive in this service; 
 The fact that most of the lines are elevated minimizes potential damage  
from fork lifts; 
 The facility has a preventive maintenance program in place designed  
to maintain the ongoing integrity of the system; 
 The facility has a training program designed to ensure that the system  
is operated by qualified personnel; and 
 The facility has emergency response procedures designed to enable  
trained personnel to respond quickly to isolate potential releases by  
closing valves in the liquid lines. 
The facility has carefully considered the potential for accidental releases of  
ammonia, such as the potential occurrence of the worst-case and  
alternative-release scenarios described in Section 2.0.  In an effort to  
minimize the probability and severity of an ammonia release, a prevention  
program t 
hat satisfies the Occupational Safety and Health Administration,  
Process Safety Management of Highly Hazardous Chemicals standard (29 CFR  
1910.119) has been implemented.  The key components of the prevention  
program are summarized below: 
 The development, documentation, and availability of critical process  
safety information regarding ammonia, the design basis of the system,  
and the equipment.  This information is used in an effort to fully  
understand and safely operate the ammonia refrigeration system. 
 The development of an employee participation program, which  
includes employees throughout the organization and from a cross  
section of areas within the plant (i.e., production and maintenance).   
This program also assumes that employees that utilize the ammonia  
system and are most knowledgeable about it are best able to easily,  
effectively, and regularly recommend changes or improvements which  
enhance safety. 
 The performance of a formal process hazard analysis (PHA 
), using the  
"What-if..." technique.  A team with expertise in engineering,  
operations, maintenance, and safety evaluated the existing  
refrigeration system in depth and developed recommendations  
designed to enhance the safety and operability of the system.  The PHA  
addressed:  (1) process hazards; (2) previous incidents, if any;  
(3) engineering and administrative controls applicable to the hazards;  
(4) the consequence of control failure; (5) facility siting; (6) human  
factors; and (7) a qualitative evaluation of possible safety and health  
effects of control system failures.  The PHA resulted in multiple  
procedural and/or hardware recommendations designed to enhance  
the safety and operation of the refrigeration system.  These  
recommendations are in the process of being resolved and many  
changes have already been implemented.  The PHA will be updated  
and revalidated every 5 years. 
 Written operating procedures (OPs) were prepared that are designed  
to provide the basis fo 
r proper and safe operation of the ammonia  
refrigeration system.  The OPs include procedures for normal  
operation, startup, shutdown, emergency operation, and emergency  
shutdown.  They also describe safe operating limits for temperature  
and pressure, the consequences of operating outside these safe  
operating limits, and a description of safety systems and how they  
 Refrigeration system operators receive refresher training at least every  
3 years.  The training content is based upon the process safety  
information and operating procedures.  The training program is  
designed to ensure that the operators understand the nature and  
causes of problems that may arise from system operation as well as the  
potential hazards particular to ammonia and the refrigeration process. 
 Formal authorization systems (i.e., management of change procedure,  
pre-startup safety review) are in place that are designed to ensure that  
system changes or expansions are as safe as the original 
design and  
that an independent recheck, prior to start-up, confirms that the  
changes are consistent with the engineering design and safety  
 Events that might (or did) cause an accidental or unexpected release of  
ammonia are subjected to a formal investigation.  The objective of the  
investigation is to address issues in such a way as to prevent  
 Contractors that are hired to work on, or adjacent to, the refrigeration  
system are "pre-qualified" based upon their knowledge of ammonia  
refrigeration, understanding of applicable codes and standards, and  
their demonstrated ability to work safely.   
 Prior to the performance of any hot work (i.e., spark or flame  
producing operations such as welding, cutting, brazing, and grinding),  
management must approve the work by executing a written hot work  
authorization permit to verify that appropriate precautions to prevent  
fire have been implemented. 
 Periodic walk-throughs occur to find unusual or in 
creasing vibration,  
incipient leaks, corrosion, or other indications of potential upsets or  
failures that could lead to a release. 
 Replacement of pressure relief valves every 5 years. 
 Numerous safety systems including pressure relief valves, monitors,  
ammonia vessel level controls, and safety interlocks are used in the  
refrigeration system. 
 Periodic inspection and calibration is performed on liquid level  
sensors, temperature and pressure instruments, switches and  
shutdown devices that have safety implications. 
 Periodic inspections are performed for major powered equipment,  
including compressors, pumps and large fans, bearings, couplings,  
shaft seals, mountings, etc., for vibration or incipient mechanical  
 Proper design including adherence to recognized safety codes, such as  
the International Institute of Ammonia Refrigeration (IIAR). 
 Adherence to fire codes and preparation for fires, storms, or events  
which could impact the ammonia system. 
lanning with the local fire department to ensure a rapid response to  
potential incidents involving the system or external events, such as  
floods or tornadoes. 
 Prevention program compliance audits performed every 3 years to  
verify that the elements are being properly implemented.  Any issues  
found in an audit are addressed in accordance with an action plan. 
The facility has not experienced a release of ammonia within the past 5 years  
(June 1994) that has resulted in on-site death, injury, or significant property  
damage or off-site death, injury, evacuation, sheltering in place, property  
damage, or environmental  
The facility has implemented a detailed written Emergency Response Plan  
(ERP).  The ERP is intended to address emergencies at the facility in  
addition to incidents related to a release of ammonia. 
The ERP includes education and response training for employees,  
coordination with the local fire department 
, coordination with the Local  
Emergency Planning Committee (LEPC), and evacuation of the facility and  
surrounding area.  Additionally, the plan details the procedures for:   
(1) pre-emergency planning; (2) emergency recognition and prevention;  
(3) site security and control; (4) decontamination; (5) emergency medical  
treatment and first aid; (6) emergency alerting and response; and  
(7) personal protective and emergency equipment. 
Centeon maintains emergency response personnel on all shifts.  Members  
of the response team participate in 40 hours of initial training, 8 hours of  
annual refresher training, as well as regular mock emergency exercises. 
   Passive mitigation means equipment, devices, and technologies that function without  
human, mechanical, or other energy input.  Examples include enclosures (e.g., buildings)  
for compressed gases and secondary containment dikes for liquids. 
   Active mitigation means equipment, devices, or technologies that require human,  
l, or other energy input to function.  Active mitigation for compressed gases,  
like ammonia, may include automatic shut-off valves, rapid transfer systems, and  
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