oEPA
United States
Environmental Protection
Agency
Office of Solid Waste
and Emergency Response
(5104)
EPA 550-F-04-005
February 2005
vwvw.epa.gov/emergencies
MANAGING CHEMICAL REACTIVITY HAZARDS
The Environmental Protection Agency (EPA) is issuing this Alert as part of its ongoing effort
to protect human health and the environment. EPA is striving to learn the causes and
contributing factors associated with chemical accidents and to prevent their recurrence. Major
chemical accidents cannot be prevented solely through regulatory requirements, but by
understanding the fundamental root causes, widely disseminating the lessons learned, and
integrating these lessons learned into safe operations. EPA publishes Alerts to increase
awareness of possible hazards. It is important that facilities, SERCs, LEPCs, emergency
responders and others review this information and take appropriate steps to minimize risk.
PROBLEM
Many materials used in
industrial facilities can pose
chemical reactivity hazards.
Conventional management systems
frequently do not adequately address
the unique behavior of materials that
may react to cause excessive
temperature or pressure excursions or
toxic or corrosive emissions.
Incidents occur not only at chemical
manufacturing and processing plants,
but also at water treatment plants,
swimming pools and spas, metal
processing facilities, and mechanical
equipment manufacturing facilities.
PURPOSE
The purpose of this alert is to
introduce facilities to the
methodology for chemical
reactivity hazard management as
developed by the Center for Chemical
Process Safety (CCPS) and made
available in a book Essential
Practices for Managing Chemical
Reactivity Hazards. This alert is a
follow-on to the recent EPA alert
which discusses the CCPS method for
screening facilities for chemical
reactivity hazards. While the first
EPA alert focused on identifying
chemical reactivity hazards, this alert
focuses on the management of the
hazards. This alert does not cover all
ten essential management practices,
but highlights some common
management deficiencies.
This alert assumes that the reader has
determined that a chemical reactivity
hazard exists at the facility and has:
• Explored opportunities, such as
substituting inherently safer
chemicals, to reduce or eliminate
reactivity hazards;
• Gathered available information
from available sources such as
MSDS.
• Completed preliminary screening
to identify chemical reactivity
hazards (see the EPA companion
alert Identifying Chemical
Reactivity Hazards: Preliminary
Screening Method for additional
information);
• Developed a matrix indicating
which chemicals react with each
other, including the process or
operating area where the chemicals
are located;
• Gained management commitment
to the safe operation of the facility;
• Ensured resources are available to
ensure physical plant is designed
or modified as necessary to
mitigate chemical reactivity hazard
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exposure;
• Implemented a sound training program,
operating procedures, and hazard
communication program; and
• Implemented an active safety audit program.
INCIDENT EXAMPLES
A number of incidents involving reactive
chemicals have resulted in accidental
chemical releases, fire, and explosions.
The following section describes several recent
incidents.
September, 2004 - A transport vessel containing a
mixture of recovered monomer was observed to be
relieving pressure via the pressure relief valve. The
relief valve was lifting (relieving) as a result of the
pressure in the vessel exceeding the relief valve
setting. The increased pressure was caused by an
increase in the temperature within the container.
This temperature increase was caused by a
polymerization reaction of the monomer mixture.
A water deluge was applied to cool the transport
vessel and minimize the vapor cloud dispersion.
The accident investigation revealed a blockage in
the injection feed line which obstructed the
addition of inhibitor into the monomer mixture.
The immediate term procedure modifications were
to manually control the inhibitor injection and,
also, to verify inhibitor concentration after loading
the transport vessel. The longer term modification
includes automatic inhibitor addition with post
loading verification of inhibitor concentration.
March, 2004 - Operations personnel were
preparing to unload a railcar of methyl chloride
when they discovered a product identification label
attached to the railcar dome reading "methylene
chloride." Because the label and placards were not
in agreement, personnel quarantined the railcar
until proper chemical verification could be made
with the supplier and the facility quality control
laboratory. The verification confirmed that the
railcar placarding for methyl chloride was correct.
Close attention to material identification used
triggered personnel to take steps to verify the
contends of the railcar, thereby reducing the
likelihood of a serious process safety incident.
March, 1997 - The facility provides an antimony
catalyst service. A 1000-pound horizontal
cylindrical container was in the process of having a
small sample drawn into an open container.
However, the handle of the quarter-turn valve
leading to the dip-leg had been removed by the
customer before returning the container of spent
catalyst. The employee opened the valve using a
vice-grip tool but was then unable to close the
valve. Escaping spent antimony catalyst was
believed to have reacted with moisture in the
atmosphere, to create hydrogen chloride. The
incident investigation led to a management-of-
change review, revised sampling procedures and
training and a closed sampling system that
discharges to a scrubber system. This incident
illustrates the need for particular attention to
operations that involve removing material from the
enclosed system, such as when venting, draining or
sampling.
July, 1994 - New steel saddles (internal saddle
shaped devices used to promote mixing) were
installed in the direct-contact chiller vessel ahead
of the chlorine compressor. The saddles should
have had no corrosion protection coating, but they
did have an undetected coating of mineral oil.
When the main stream of chlorine and the chilling
material, which was also chlorine, entered the
chiller vessel, there was an intense exothermic
reaction between the chlorine and the mineral oil
which burned through the vessel wall, releasing
chlorine to the atmosphere. The subsequent
incident investigation, the management-of-change
review, and the operating procedure revision
focused on verification that mechanical equipment
that may come into contact with chlorine is
confirmed to be free of any material with which
chlorine may react. This incident highlights the
need to consider not only process chemicals, but
other chemicals and contaminants as well.
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MANAGEMENT OF REACTIVE
HAZARDS
The consequences of a reactive chemical
incident can be severe. In a 2002 study, the
U.S. Chemical Safety Board (CSB) collected
detailed information on 167 serious incidents that
occurred between 1980 and 2001. EPA reviewed
CSB's information and identified the most
commonly reported management deficiencies. In
order of frequency, the reported management
deficiencies are:
• Operating Procedures, Safe Operating Limits
and Training
• Hazard Identification and Evaluation
• Human Factors
• Management of Change
• Emergency Relief Equipment and Controls
• Process Design
• Process Knowledge
• Incident Investigation
• Process Hazard Analysis
• Safety Auditing
• Equipment Maintenance
In their Reactive Hazard Investigation report, CSB
points to the limited availability of accurate
reactive chemical incident data. In spite of these
limitations, we believe that this data set is useful in
identifying areas of management systems that need
to be strengthened in order to address the hazards
of reactive chemicals.
To assist facilities in managing these risks, the
Center for Chemical Process Safety (CCPS)
sponsored the concept book Essential Practices for
Managing Chemical Reactivity Hazards and with
the support of its government and industry partners
has made this book available free of charge from
the Internet. Chapter 4 of this book discusses ten
essential practices for managing chemical
reactivity hazards. This alert does not cover all ten
management practices but highlights some
common management deficiencies.
Recommendations for strengthening management
systems include:
Communicate and Train on Chemical
Reactivity Hazards
Training activities and materials should
incorporate the hazards of chemical reactivity and
provide information relevant to workers directing
and performing process operations. The following
are some suggestions for improving
communication and training about reactive hazards
within a facility:
• State not only the steps required to correctly
execute the operation, but also the
consequences of deviation. Develop likely
scenarios such as incorrect charging,
contamination of the process, or operating the
process in the wrong range.
• Integrate information about chemical reactivity
hazards into the operating procedures and
instructions, rather than separately appending it
to the instructions.
• Clearly state safe operating limits and the
actions to be taken if operating deviations
occur.
• Because concepts concerning reactivity hazards
may be unfamiliar to some operating staff, these
concepts should be clearly and simply worded.
• Chemical reactivity hazards information should
be included in the facility's material safety data
sheet (MSDS) and, if necessary, described in
detail in instructions accompanying the MSDS.
• Share training materials with all operating
personnel, including contractors.
• Facility management should ensure that training
is understood by employees and contractors.
Identify Process Controls and Risk
Management Options
The materials receiving and transfer system should
be designed to guard against inadvertent mixing or
incorrect handling.
• Material receipt - Is a procedure in place,
possibly sampling, to check the material
received to ensure that it is the correct material?
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• Connection points- Is the connection clearly
marked and/or color coded to guard against
delivering to the wrong point? Incompatible
couplings may also have an application.
• Have piping manifolds, including sampling
lines, blow-down and venting or flaring systems
been checked to guard against cross connections
that can lead to inadvertent mixing?
• If incompatible materials are not handled in
dedicated systems, are there positive isolation
methods (spectacle blinds, drop-out, double
block and bleed valve stations) used to prevent
inadvertent mixing?
• Positive Materials Identification (PMI) - Has
the material handling equipment been checked
to ensure that it is suitable for the material to
which it is exposed? In addition to the piping,
vessels, pumps and valving, the internal trim,
packing, and lubrication and sealant must be
considered.
Appropriate safeguards should be considered to
minimize hazards related to storage of reactive
materials.
• Can the material deteriorate and become
unstable because of the ambient temperature
being too high, or too low, or because of
excessive shelf time?
• If containment is breached, will materials
become exposed to air or water to which they
are reactive?
• Are incompatible materials stored the proper
distance apart, or otherwise isolated?
• Can breached containers allow incompatible
chemicals to mix and react?
• Has equipment used in the storage area been
evaluated to ensure that it will not act as a heat
or ignition source or cause instability (example
- fork-lift truck exhaust in a dusty
environment)?
• Are sensors and alarms located in the storage to
alert personnel in the event of a release or slow
leak?
Manage Process Knowledge
Technical information pertaining to fire protection,
safety, health and environmental protection should
be freely exchanged between organizations within
industry and by technical societies.
• Does the facility management have at least one
person designated to explore available
information on chemical reactivity hazards that
may pertain to their operations?
• Is information gathered from the above sources
distilled down into an understandable form and
made available to persons that may be involved
with or exposed to the hazards of reactive
chemicals present at the operating facility?
• Is every opportunity taken to upgrade operating
procedures and instructions as new information
becomes known?
• Is facility management strongly encouraged to
contribute its own new information, including
lessons learned and near-misses to others within
industry?
Conduct a Process Hazard Analysis (PHA)
Many methods of conducting a PHA are suitable
for assessing the hazards associated with operation
of facilities involving reactive materials or
mixtures. Several methods, such as "hazard and
operability" and "what-if," rely on a base set of
questions for identifying risks. These base sets of
questions should be expanded to include aspects
that may be unique to reactive chemicals.
Additionally, any process change that is made
should receive a management of change (MOC)
review.
Consider Abnormal Situations
The severity of many chemical accidents can be
attributed to a reluctance to seriously consider all
scenarios and to develop an appropriate action
plans. Identifying and evaluating deviations that
may occur and developing appropriate responses
must be thought out before the fact. Possible
abnormal situations must be documented and
incorporated into instructions and training for
operating personnel and for emergency responders.
Otherwise, there is likely to be no response or an
inadequate one. Some questions that should be
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considered:
• What out-of-control conditions are possible?
What remedial steps are authorized and by
whom?
• What firefighting actions may be taken?
What actions should be avoided?
• Is emergency response equipment
appropriately located and accessible in all
types of situations?
• Which neutralizing or mitigation initiatives
may be taken?
• What secondary hazards may result from
pressure relief or blow-down systems?
• What contaminants are likely to be
encountered?
Conduct Frequent Audits
Safety, health and environmental (SHE) audits can
serve a number of invaluable functions, including
verification that the concepts of reactive chemical
hazards are understood by operating personnel and
have been built into the operation. The SHE audit
may be the last line of defense against an accident.
In verifying that the management system is
reliable, the SHE audits can also serve as an
excellent training activity for key personnel and for
"guest" audit participants. Audits provide an
opportunity for input from individuals in all levels
of the organizations. Audit teams must also
include at least one person with a good
understanding of the methods for identifying
chemical reactivity hazards. Team members
should be familiar with the different elements of a
sound management system and be able to
determine if each element is functioning as
intended. The effectiveness of the training
programs and the operating procedures should be a
focal point of the audit program.
RECOMMENDED READING
Essential Practices for Managing Chemical
Reactivity Hazards - 2003, 194 pages, - Chemical
Center for Process Safety (CCPS).
CCPS has teamed with US OSHA, US EPA, the
American Chemistry Council, the Synthetic
Chemical Manufacturers Association, and Knovel
corporation to make this important new CCPS
concept book available for free on the Internet.
"Essential Practices" identifies a simple process to
determine if your operation may be at risk of a
chemical reactivity incident, and then guides you
to resources to manage that risk. Persons wishing
free online access to this book will need to follow
a one-time sign-up procedure through Knovel,
CCPS's on-line book distributor, prior to gaining
access to the document.
http: //info. knovel. com/ccp s/
Chemical Safety Alert: Identifying Chemical
Reactivity Hazards Preliminary Screening
Method- 2004, 5 pages - US EPA.
The purpose of this alert is to introduce small- and
medium-sized facilities to a simple method
developed by the Center for Chemical Process
Safety (CCPS), published in Essential Practices
for Managing Chemical Reactivity Hazards, to
screen facilities for chemical reactivity hazards.
http ://yosemite. epa. gov/oswer/ceppoweb .nsf/vwRe
sourcesByFilename/flowchart.pdf/SFile/flowchart.
rjdf
A Checklist for Inherently Safer Chemical
Reaction Process Design and Operation What
You Need to Know - 2004, 8 pages - Chemical
Center for Process Safety (CCPS).
CCPS has developed this free pamphlet as a
summary of basic principles for safe operation of
chemical reaction processes.
http://www.aiche.org/ccps/pdf/CCPSAlertChecklis
t.pdf
Reactive Material Hazards What You Need to
Know - 2001, 11 pages - Chemical Center for
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Process Safety (CCPS).
CCPS has developed this free pamphlet to help
safety managers, chemists, and engineers
determine whether a process could have a chemical
reactivity hazard and what they should do to
prevent potential hazards.
http://www.aiche.org/ccps/pdf/reactmat.pdf
SOME USEFUL WEBSITES
OSHA Reactives Alliance
http://www.osha.gov/dcsp/alliances/reactives/react
ives.html
OSHA Chemical Reactivity Safety
http ://www. osha. gov/dep/reactivechemicals/
Mary Kay O'Connor Process Safety Center-
Reactive Chemical Research
http://process-safety.tamu.edu/research/reactiveche
m_l ab/RC_home. htm
National Oceanic and Atmospheric
Administration (NOAA) Chemical Reactivity
Worksheet
http://response.restoration.noaa.gov/chemaids/react
.html
FOR MORE INFORMATION...
Contact the RCRA, Superfund & EPCRA
Call Center at:
(800) 424-9346 or (703) 412-9810
TDD (800)553-7672
Monday -Friday
9 AM to 5 PM, Eastern Time
Visit the OEM Home Page at:
http://www.epa.gov/emergencies
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