United States         Occupational Safety      Bureau of Alcohol,
Environmental Protection       and         Tobacco, Firearms
Agency           Health Administration       and Explosives

            EPA 550-S-13-001 August 2013
       Chemical Advisory:
  Safe Storage, Handling, and
  Management of Ammonium

Chemical Advisory: Safe Storage, Handling, and Management of Ammonium Nitrate                    August 2013

The Environmental Protection Agency (EPA), the Occupational Safety and Health Administration (OSHA),
and the Bureau of Alcohol, Tobacco, Firearms, and Explosives (ATF) ("we") are issuing this advisory1 as
part of an ongoing federal effort to improve chemical risk management, and to advance safety and
protect human health and the environment. This advisory contains information on recent and past
accidents involving AMMONIUM NITRATE (commonly referred to as AN), on the hazards of AN, how to
manage these hazards, and appropriate steps for community emergency planning and proper
emergency response. It is focused primarily on safe handling and storage of higher density, solid AN
pellets and prills (a prill is a  small bead) used in fertilizers. This advisory is intended to broadly
disseminate lessons learned from recent incidents involving AN so that such incidents can be prevented
in the future. Also provided is a list of information resources, including relevant codes and standards,
industry publications, and applicable statutes and regulations that will help facilities handling AN and
first responders better understand the hazards so they can effectively manage the risks. The
information provided is not intended to cover all the hazards, safe practices or technical challenges
associated with the manufacturing of AN; liquid fertilizers containing AN; manufacturing, storage or use
of explosives or blasting agents containing AN; or the transportation of AN. For these particular
situations, please consult other sources  including the appropriate references, standards and regulations,
cited at the end of this document.

In general, AN is manufactured for use as a fertilizer and to produce explosives and blasting agents.2
There are several other uses in the chemical industry, such as the production of nitrous oxide.  These
other uses represent a small fraction of amount of AN used in the US.

Although pure AN is stable at ambient temperature and pressure under many conditions, the chemical
itself does not burn. AN is a strong oxidizer3 and it supports and accelerates the combustion of organic
(and some inorganic) material, increasing the fire hazard and complicating the fire fighting challenges.
AN may explode when exposed to strong shock or when subjected to high temperatures in confinement.

Millions of tons of AN are produced annually in the US.  Incidents involving AN are rare, but as is shown
in the accidents below, they can have severe consequences. Most recently, on April 17, 2013,  a fire at a
fertilizer storage and distribution facility in West, Texas, resulted in a detonation of AN fertilizer stored
at the facility, killing 15 people, including some of the firefighters responding to the fire. That incident
remains under investigation,4 but much  has been learned from other AN explosions.
1 The statements in this document are intended solely as guidance. This document is not a substitute for EPA, OSHA, ATF or other agencies'
regulations, nor is it a regulation itself.  It cannot and does not impose legally binding requirements on the agencies, states, orthe regulated
community. The measures described in this document may not apply to a particular situation based upon the circumstances. This guidance
does not represent final agency action and may change in the future, as appropriate.
2 A blasting agent is any material or mixture, consisting of a fuel and oxidizer, intended for blasting, not otherwise classified as an explosive and
in which none of the ingredients are classified as an explosive, provided that the finished product, as mixed and packaged for use or shipment,
cannot be detonated by means of a No. 8 test blasting cap when unconfined (see 29 CFR 1910.109(a)(l))
3 An oxidizer is a material that readily yields oxygen or other oxidizing gas or that reacts readily to promote or initiate combustion of
combustible materials.
4 The precise quantity and form of AN has not been definitively established. We intend to update this advisory as we learn more about the
incident and as we identify additional best practices.

Chemical Advisory: Safe Storage, Handling, and Management of Ammonium Nitrate                    August 2013

       On October 2, 2003, a fire and explosion occurred in a double story farm warehouse in St.
        Romain en Jarez, France, involving 3 to 5 tons of AN stored in bags. This incident killed 26
        people, 18 of whom were firefighters.  In this incident, improper storage methods are thought
        to have played a role.

       On September 21, 2001, a massive explosion occurred in a warehouse at the Azote de France
        fertilizer factory in Toulouse, France, involving 200-300 tons of AN, which was stored in bulk in a
        hangar. The explosion resulted in the death of 30 people, 2500 injuries, the destruction of the
        factory, and an  additional 10,000 buildings being heavily damaged. The exact cause of this
        accident remains unknown. Storage of incompatible material with AN is believed to have been a

We have learned several key lessons as a result of these accidents and additions studies of AN,

The conditions of storage and the materials co-located with AN while in storage are crucial to the
safety and stability of the AN.

Explosions of stored AN are responsible for some of the worst chemical disasters on record. Several of
these incidents, including two in Germany in 1921, occurred during attempts to break up large piles of
solidified or caked AN and ammonium sulfate mixtures using explosives. In both cases, the initial blast
intended to break up solid AN initiated an unintended general detonation of the AN or ammonium
sulfate mixture.

AN will self-confine under some conditions.  Adding heat, such as a booster charge intended to break
up clumps, can initiate a general detonation of the AN.

Other large explosions have been triggered by fires involving AN in confined spaces, including the 1947
explosion in Texas City,  Texas, of two cargo ships. In that case, the first  ship is thought to have exploded
due to a fire in the hold involving AN fertilizer that had been  manufactured with a wax coating and
stored in paper bags.  The wax would have been one potential source of fuel for mixing with the AN,
thus creating an explosive situation. The second ship exploded some time later, likely due to a fire
caused by the first explosion. These two explosions resulted in deaths of nearly 600, including all but
one member of the Texas City Fire Department.

As a  result of such accidents and subsequent studies of the properties of AN, caked AN is no longer
broken up with explosive materials, and organic material such as wax coatings are no longer used for AN

Our intent in issuing this advisory is to identify actions that should be taken as a result of the lessons
learned from the more recent accidents involving AN. Similar to the corrective steps taken following the
1921 and 1947 incidents, this advisory emphasizes the safe steps that should become common practice
in the industry and emergency response community in order to prevent the catastrophic loss of life and
property damage.

Chemical Advisory: Safe Storage, Handling, and Management of Ammonium Nitrate                    August 2013

Here are some of the things we have learned from accidents involving AN:

  AN will self-compress/self-confine under some conditions, becoming much more likely to explode.

AN is at risk for explosion when stored near other material that can add fuel to the AN - such as grain,
             sugar, seeds, sawdust, and most especially petroleum fuels such as diesel.

  AN is a powerful oxidizer and a rich source of nitrate, which provides energy to an explosion. Thus,
    the presence of fuel and/or heat (and especially both) near AN is a very high hazard situation.


Hazard Classification

For the purpose of transportation, AN that contains less than 0.2 percent combustible substances and
AN fertilizers are classified by the  U.S. Department of Transportation (DOT), as oxidizers. AN with more
than 0.2 percent combustible substances is classified by DOT as an explosive.5 (see box below).

The National Fire Protection Association (NFPA) assigns an instability rating of 3 (in  a range of 0-4) to AN,
meaning AN is capable of detonation, explosive decomposition,  or explosive reaction, but that a strong
initiating source or confinement in extreme temperatures is required.  AN can explode under certain
conditions by adding energy (heat, shock), especially when contaminants are present or it is under

     "Pure" ammonium nitrate is stable and will explode only under extraordinary circumstances.
However, the addition of combustible materials such as sugar, grain dust, seed husks or other organic
  contaminants, even in fairly low percentages, creates a dangerous combination  and the ammonium
nitrate mixture becomes far more susceptible to detonation. This characteristic of ammonium nitrate
        underlies most of the advice and recommendations for safe handling contained herein.

Decomposition Chemistry

AN melts at 337 F (170 C) and begins to undergo decomposition when molten.  Hazardous scenarios
with AN can involve simple thermal decomposition initiated by external fire or other heating, self-
sustained decomposition also known as "cigar burning," and detonation.

Decomposition creates toxic gases containing ammonia and nitrogen oxides.  The resulting nitrogen
oxides will support combustion, even in the absence of other oxygen. The resulting heat and pressure
from the decomposition of AN may build up if the reaction takes place in a confined space and the heat
5 Explosive means any substance or article, including a device, which is designed to function by explosion (i.e., an extremely rapid release of gas
and heat) or which, by chemical reaction within itself, is able to function in a similar manner even if not designed to function by explosion (see

Chemical Advisory: Safe Storage, Handling, and Management of Ammonium Nitrate                    August 2013

and gases created are not able to dissipate. As the temperature rises, the rate of decomposition
increases. In a confined space, the pressure can reach dangerous levels and cause an explosion that will
include the detonation of the AN.

When dealing with a large quantity of AN, localized areas of high temperature may be sufficiently
confined by the mass of material to initiate an explosion. The explosion of a small quantity of AN in a
confined space (e.g., a pipe) may act as a booster charge and initiate the explosion of larger quantities
(e.g., in an associated vessel).

During a fire in a facility where AN is present, the AN can become hot and molten which makes the
material very sensitive to shock and detonation, particularly if it becomes contaminated with
incompatible material such as combustibles, flammable liquids, acids, chlorates, chlorides, sulfur,
metals, charcoal, sawdust, etc. If a molten mass becomes confined (e.g., in drains, pipes or machinery),
it can explode.

Most types of AN do not continue to decompose once a fire has been extinguished. However, some
types of AN fertilizers containing a small percentage of chlorides (e.g., potassium chloride) undergo a
smoldering (self-sustaining) decomposition that can spread throughout the mass to produce substantial
toxic fumes, even when the initial heat source is removed. These fertilizers that can self-sustain
decomposition, known as "cigar burners" are normally compound fertilizers that contain between 5% to
25% nitrogen from ammonium nitrate, up to 20% phosphate (as P2O5) and chloride (which may only be
present as a small percentage).


AN mixed with oil or other sensitizing  contaminants may explode or detonate when exposed to fire or
shock.  Organic materials (e.g., packing materials, seed, etc.) will increase the likelihood of an explosion
and will make the AN explosion more  energetic.

AN may also be sensitized by certain inorganic contaminants, including chlorides and some metals, such
as aluminum powder, chromium, copper, cobalt, and  nickel.

As AN solution becomes more acidic, its stability decreases, and it may be more  likely to explode.

Solid AN readily absorbs moisture, which can lead to caking, self-compression and self confinement.
This in turn increases susceptibility to  explosion in a fire.

The density, particle size and concentration of solid AN in a material, as well as the presence of other
additives, affects the hazard of the material. The technical grade of AN is a lower density (higher
porosity) prilled material.  Higher density prills are used as fertilizer. AN can be fused with ammonium
sulfate fertilizer or  amended with carbonate materials to reduce its explosive properties. More
information on additives is discussed in Guidance for the Storage, Handling and Transportation of Solid
Mineral Fertilizers found in the Reference section. Solid fertilizers are usually coated with an  inorganic,
non-combustible anti-caking compound to prevent sticking and clumping.

Chemical Advisory: Safe Storage, Handling, and Management of Ammonium Nitrate                    August 2013

AN in undiluted or pure form has a higher degree of overall hazard than when it is mixed or blended
with compatible or non-combustible materials that can reduce the concentration. In general for
fertilizer blends containing AN, the more nitrogen they contain, the greater the explosion hazard they
pose. Blended fertilizers containing AN and chloride compounds and blended fertilizers containing AN
contaminated with combustible materials or incompatible substances pose increased explosion hazards.
A large number of blended fertilizers are produced from basic primary fertilizer products (e.g.,
ammonium nitrate, urea, and mono-ammonium phosphate) and natural materials (e.g., rock phosphate,
potassium chloride) which can introduce contaminants. All such materials are not necessarily
compatible with each other and some may produce undesirable effects when mixed with others. These
undesirable effects can include, for example, chemical reaction(s) and physical effects (e.g. stickiness
which can cause handling difficulties, moisture migration giving rise to caking tendency). Facilities can
consult Guidance for Compatibility of Fertilizer Blending Materials listed in the Reference section to
assess potential incompatibility. The Safety Data Sheet (SDS - formerly MSDS) of the AN  product should
be used as one source of information to assess the overall hazard. The effects of added components can
only be determined after careful review of the SDS and other available hazard literature.

  Confinement and/or the addition of fuel to AN creates a real danger of explosion. The addition of
  heat when either of these conditions exists can lead to disaster. Accordingly, the responder should
quickly assess if AN has been involved in the fire and whether the AN has been compromised in any of
                        these ways, and plan the fire response accordingly.

What steps should facility owners or operators take to reduce the hazards of AN during
storage and handling?

Storage/Process Conditions to Avoid

Persons engaged in the handling, management or emergency planning for AN must be aware of the
hazards of AN and ensure that the conditions that may lead to an explosion are not present.  Measures
that facilities should take to ensure the safe storage, use and handling of AN include:

       Avoid heating AN in a confined space.
           o  Processes involving AN should be designed to avoid this possibility.
           o  Avoid localized heating of AN, potentially leading to development of high temperature
              areas (e.g., AN fertilizer should not be stored near sources of heat such as steam pipes,
              radiators, hot ducts, light bulbs etc.).
       Ensure that AN is not exposed to strong shock waves from explosives.  AN storage near high
       explosives or blasting agents must conform to ATF's Table of Separation Distances, Title 22 of
       the Code of Federal Regulations, section 555.220 (22 CFR 555.220).

Chemical Advisory: Safe Storage, Handling, and Management of Ammonium Nitrate                    August 2013

       Avoid contamination of AN with combustible materials or organic substances such as packing
        materials, dust, seed, oils, and waxes.
           o  If possible, do not co-locate AN, especially bulk AN in bins, with dust-producing organics
               such as grains or seeds.
       Avoid contamination of AN with inorganic materials that may contribute to its sensitivity to
        explosion, including chlorides and some metals, such as aluminum powder, chromium, copper,
        cobalt, and nickel.
           o  Pay attention to the materials used to build storage areas and cribs. Wood and
               aluminum or other metals must be specially treated to prevent impregnation if they are
               going to be in contact with AN.  Metal materials can be treated with epoxy tar or
               chlorinated rubbers to prevent corrosion of the metal and contamination of the AN.
       Maintain the pH of AN solutions within the safe operating range of the process. In particular,
        avoid low pH (acidic) conditions.
           o  If possible, do not co-locate acids in an AN storage area.
       Keep molten or solid AN out of confined spaces, especially sewers or drains where it can react
        with organic materials there.

Certain  specific safety and handling instructions (required and recommended) apply for safe handling
and storage of AN6 under certain conditions:

    OSHA's standard for Explosives and Blasting Agents at 29 CFR 1910.109(i) contains requirements for
    AN stored in the form  of crystals, flakes, grains or prills including fertilizer grade, dynamite grade,
    nitrous oxide grade, technical grade, and other mixtures containing 60 percent or more of AN by
    weight. AN should also be handled in accordance with safe practices found in NFPA 400 Hazardous
    Materials Code, Chapter 11.

    Building Design

       Store only in one-story buildings and buildings with no basements, unless the basement is open
        on one side.
       Use fire resistant walls within 50 feet of combustible building or materials.
       Flooring in storage and handling areas should be constructed of  noncombustible material or
        protected from impregnation by AN.
       Avoid installing, or remove or close off any open drains, traps, tunnels, pits or pockets into
        which molten AN can flow and be confined in the event of fire.
       Buildings should be kept dry and free of water seepage through  roofs, walls and floors.
       Have adequate ventilation or be constructed to self-ventilate in the event of a fire to avoid
       Do not place AN into storage when the temperature of the product exceeds 130F (54.4C).
 AN-based materials that are DOT Hazard Class 1 sensitive (explosives or blasting agents) must be handled and stored in accordance with
requirements of OSHA's Standard for Explosives and Blasting Agents (29 CFR 1910.109) and ATF's Table of Separation Distances of Ammonium
Nitrate and Blasting Agents from Explosives or Blasting Agents (27 CFR 555.220) Facilities should also follow the NFPA 495- Explosive Materials
Code, where applicable.

Chemical Advisory: Safe Storage, Handling, and Management of Ammonium Nitrate                    August 2013

    Storage in bags, drums or other containers

       Piles of bags, drums and other containers should be no closer than 36 inches below the roof or
       supporting beams.
       Bags should be stored no less than 30 inches from walls or partitions.
       Piles of bags, drums, and other containers should not exceed a height of 20 feet, width of 20
       feet, and length of 50 feet, unless the building is of noncombustible construction or protected
       by automatic sprinklers.
       Maintain aisles of at least 3 feet width between piles.

    Storage in bulk

       Bins for storing bulk AN should be kept clean and free of materials, which could contaminate the
       material. Bins should not be constructed of galvanized iron, copper, lead or zinc unless suitably
       protected.  Aluminum or wooden bins should be protected against impregnation by AN.
       Piles or bins must be adequately sized, arranged and moved periodically to minimize caking.
       Height or depth of piles shall be limited by pressure-setting tendency of the product, but in no
       case should pile be higher than 36 inches below roof or supporting beams.
       Do NOT use dynamite, explosives or blasting agents to break up or loosen caked AN.
       Protect piles of AN from absorbing moisture from humid air by covering them with water-
       impermeable sheeting or using air conditioning.
       Do not store AN with organic chemicals, acids, or other corrosive materials, materials that may
       require blasting during processing or handling, compressed flammable gases, flammable and
       combustible materials or other contaminating substances. AN stores should be separated from
       incompatible substances by using separate buildings or 1 - hour fire resistant walls, or  a
       minimum separation distance of 30 feet.

    Fire Protection

       AN storage areas should be equipped with an automatic sprinkler system, or have an automatic
       fire detection and alarm system if the areas are not continuously occupied. This is especially
       important when the facility in  question is close to the public surrounding the facility.
       Facilities should NOT store more than 2500 tons of bagged AN without an automatic sprinkler
       An automatic sprinkler system, if installed, should be  provided in accordance with NFPA 13,
       Standard for the Installation of Sprinkler Systems.
       Suitable fire control devices such as hoses and appropriate portable fire extinguishers (AN is an
       oxidizer and not all fire extinguishers are appropriate) shall be provided throughout the
       warehouse and loading areas. Water supplies and fire hydrants should be available.
       Store AN fertilizer in separate  buildings or separated by approved fire walls from organic,
       combustible or reactive materials, such as grains, wood or other organic materials, urea and
       urea compounds, flammable liquids or gases, corrosive acids, chlorates, chromates nitrites,
       permanganates or finely divided metals or sulfur.


Chemical Advisory: Safe Storage, Handling, and Management of Ammonium Nitrate                   August 2013

       AN fertilizer should NOT be stored in the same building with explosives or blasting agents unless
       conditions in ATF's Table of Separation Distances of Ammonium Nitrate and Blasting Agents
       from Explosives and Blasting Agents, 27 CFR 555.220, are met.
       Prohibit smoking in AN storage areas.

      We recommend that AN be stored in purpose-built facilities/buildings of non-combustible
 construction. Dust-producing organic materials, such as grain, seeds and sugar, should not be stored
near AN. Some metal powders such as aluminum powder are equally dangerous.  AN should be stored
so as to ensure it is not contaminated by gasoline, diesel or other fuels, and is not subject to high heat
                 (even in one small area of a large stockpile) or water infiltration.

What should communities do to understand and develop a plan for the risk associated with

AN is a hazardous chemical covered under the OSHA Hazard Communication Standard. Therefore,
facilities that handle and store AN are required by law to submit information regarding chemical hazards
(including AN) to their State or Tribal Emergency Response Commission (SERC or TERC), Local Emergency
Planning Committee (LEPC), and local fire department. This  information must include the following:

    1)  a Safety Data Sheets (SDS) providing the chemical's hazard information and emergency response
       guidelines and
    2)  a Hazardous Chemical Inventory form that provides the quantity, storage types and locations of
       the AN at their facility.

We recommend that fire services visit any facility reporting AN, and that the conditions of storage and
     manner of handling be reviewed by fire service personnel. Fire service and other emergency
    responders should take note of the specific location (s), amounts and packaging of stored AN.
    Conditions of storage should be reviewed with the facility operator in light of the information
                                 provided in this document.

The LEPC in conjunction with the fire department should use this information to develop an emergency
plan, in case of a fire or explosion involving AN or any other hazardous substance. The facility should
consult with the LEPC to  provide them the necessary information to develop the emergency plan, the
elements of which should include:

       Identification of facilities and transportation routes of hazardous substances
       Description  of emergency response procedures, on and off site
       Designation of a  community coordinator and facility emergency coordinator(s) to implement the

Chemical Advisory: Safe Storage, Handling, and Management of Ammonium Nitrate                   August 2013

       Outline of emergency notification procedures
       Description of how to determine the probable area and population affected by releases
       Description of local emergency equipment and facilities and the persons responsible for them
       Outline of evacuation plans
       A training program for emergency responders (including schedules)
       Methods and schedules for exercising emergency response plans

LEPCs should also ensure that members of the community (which would include potentially affected
populations) are aware of the emergency plan and the actions they need to take if an accident occurs.

Local fire departments should use the information to determine what precautions they may need to
take in responding to an accident at the facility and ensure the first responders have the appropriate
training to respond to incidents  involving AN.

Owners and operators of facilities holding AN are required to report the AN hazard to local response
officials under the Emergency Planning and Community Right-to-Know Act (EPCRA). Unfortunately, that
obligation is not universally understood, and so some facilities may fail to report.  Fertilizer-grade AN is
typically found at those businesses that provide direct logistical support to agriculture. This may include
crop service operations, farm co-ops, grange stores and similar operations.

 In the interest of community safety, it is often necessary and appropriate for first response officials to
   reach out to facility owners and operators, and determine if unreported risks  are present in their
community. Helping a neighbor, facility operator, or employer to understand and meet his obligations
                  to the community and to workers is in everyone's best interest
Owner/operators of storage facilities should develop a site emergency response plan which includes:

       Coordination with local first responders
       Joint training with first responders if possible
       Employee training
       Community outreach
       Analysis of what may be at risk in a serious accident and appropriate planning
       Signs that clearly mark high hazard areas, safe areas, emergency contact numbers, firefighting
       equipment, and other essential area during an emergency response
       A site and area evacuation plan

  Owners and operators of facilities holding AN have an obligation to ensure their community's first
responders are aware of the hazards associated with the AN. Reliance on a report may not always be
sufficient. Owners and operators should take a pro-active approach to reaching out to the emergency
    response officials in their location and ensuring that the hazards of AN are understood by the

Chemical Advisory: Safe Storage, Handling, and Management of Ammonium Nitrate                   August 2013

What do firefighters need to know when responding to an accident or fire involving AN?

Before responding to a fire involving AN, firefighters should ensure the community emergency response
plan includes:

       AN hazard information and emergency response guidelines
       Quantity, storage types, and locations of AN at facilities in their community
       Specific response procedures; including a decision process to determine under which conditions
       a fire should be fought or whether the fire should be allowed to burn
       Evacuation procedures for the community
       Training requirements for all response personnel
       A schedule for exercising the response plan related to AN accidents

When responding to a fire where AN is stored; firefighters should:

       First consider if they can safety fight the fire or whether they should  just let it burn, move to a
       safe location, and focus on evacuating nearby residents and preventing further safety issues for
       the surrounding community.

To determine whether or not it makes sense to fight the fire or to let it burn, firefighters and emergency
responders should consider the following information:

       Firefighters should not fight an AN fire and everyone, including fire fighters, should be
       evacuated to a safe distance if they observe any of the following:
       o   A fire involving AN is judged to be out of control;
       o   The fire is engulfing the AN; or
       o   Brown/orange smoke is detected, indicating the presence of nitrogen dioxide (which is
           toxic); or
       o   A rapid increase in the amount/intensity of smoke or fire in the area of AN storage.

       If firefighters consider it safe and appropriate to respond to a fire involving AN, then the
       following information should  be considered:
       o   AN fires should be fought from protected locations or maximum  possible distance.
           Approach a fire involving or close to AN from  upwind to avoid  hazardous vapors and toxic
           decomposition products.  Self-contained breathing apparatus (SCBA) of types approved by
           the National  Institute for Occupational Safety and Health (NIOSH) should be used to protect
           personnel against gases.
       o   Use flooding quantities of water from a distance as promptly as possible.  It is important
           that the mass of AN be kept cool and the burning be quickly extinguished.  Keep adjacent
           fertilizers cool by spraying with large amounts of water.  When possible and appropriate,
           only use unmanned hose holders or monitor nozzles.

Chemical Advisory: Safe Storage, Handling, and Management of Ammonium Nitrate                   August 2013

        o   Do NOT use steam, CO2, dry powder or foam extinguishers, sand or other smothering
        o   Ensure maximum ventilation of the AN storage container as quickly as practical to prevent
           heat and pressure buildup. This is different than ensuring maximum ventilation of the
           entire building or structure where the AN is stored. Ventilation of the structure should be
           conducted only in a manner to limit fire spread and growth and should be minimized until a
           suppression water supply is established.
        o   If practicable and safe to do so, attempt to prevent AN from entering the drains where
           explosive confinement could occur.  Remember AN may be washed into drains by fire
           water, but it can also melt and flow without impetus from water.
        o   Prevent or minimize contamination of water bodies or streams to reduce the potential for
           environmental effects.


NFPA codes and Compressed Gas Association (CGA) standards are developed through a consensus
standards development process approved by the American National Standards Institute.  This process
brings together volunteers representing various viewpoints and interests to achieve consensus on safety
issues. These codes and standards are not binding but may be adopted by reference into laws or
regulations. Users of the codes and standards should consult applicable federal, state and local laws and

NFPA has developed a code for storage of AN, including mixtures containing 60 percent or more by
weight of AN, and a code for explosives that would apply to blasting agents and explosives containing
AN. These codes are listed below:

       NFPA 400  Hazardous Materials Code, Chapter 11 - Ammonium Nitrate Solids and Liquids.
       (2013).  Also see Annex A.ll in this document and Annex E:  Properties and Uses of Ammonium
       Nitrate and Fire-Fighting Procedures.

       NFPA 495  Explosive Materials Code (2013).

       National  Fire Protection Association
       1 Batterymarch Park
       PO  Box 9101
       Quincy, MA 02169-7471
       Phone: 800-344-3555 (toll free)
       Website: http://www.nfpa.org/freeaccess
 Keep in mind that ammonium nitrate is an oxidizer-that is- it provides its own oxygen and once combustion begins, it cannot be smothered.
Moreover, the combination of heat and confinement will accelerate combustion, perhaps to the point of detonation.

Chemical Advisory: Safe Storage, Handling, and Management of Ammonium Nitrate                    August 2013

Safe Practices for the Production of Nitrous Oxide From Ammonium Nitrate, CGA G-8.4  (January 2013).
Compressed Gas Association, Inc., Chantilly, VA
http://www.cganet.com/customer/publication  detail.aspx?id=G-8.4


Storing and Handling Ammonium Nitrate, INDG230 (First published 8/96, Reprinted 11/04).  Health and
Safety Executive (HSE), United Kingdom http://www.hse.gov.uk/explosives/ammonium/

Safe Storage and Handling of Ammonium Nitrate (AN), Technical Note 60, (28/02/2006), SafeWork,
South Australia,  http://www.safework.sa.gov.au/uploaded files/SSAN  Storage.T60.pdf

Safe Practice: Safe Storage of Solid Ammonium Nitrate. (2013). Resources Safety, Division of Mines and
Petroleum, Government of Western Australia (WA), East Perth, WA.
http://www.dmp.wa.gov.au/documents/Code of Practice/DGS COP  StorageSolidAmmoniumNitrate.

Guidance for the Storage, Handling and Transportation of Solid Mineral Fertilizers. (2007). European
Fertilizers Manufacturers Association, Brussels,  Belgium, www.efma.org

Guidance for the Safe Handling and use of Non-conforming Fertilizers and Related Materials (Producers).
(2003). European Fertilizers Manufacturers Association, Brussels, Belgium, www.efma.org

Guidance for the Safe Handling and Use of Non-conforming Fertilizers and Related Materials for Fertilizer
Importers, Distributors and Merchants. (2004). European Fertilizers Manufacturers Association, Brussels,
Belgium, www.efma.org

Guidance for the Storage of Hot Ammonium Nitrate Solution. (2005). European Fertilizers Manufacturers
Association, Brussels, Belgium,  www.efma.org

Guidance for Compatibility of Fertilizer Blending Materials. (2006).  European Fertilizers Manufacturers
Association, Brussels, Belgium,  www.efma.org

    The above five guidance documents from European Fertilizers  Manufacturers Association can be
    found on the following webpage:


Ammonium Nitrate and Mixed Fertilizers Containing Ammonium Nitrate, FM Global Property Loss
Prevention  Data Sheet 7-89. (April 2013). FM Global, Johnston, Rhode Island.
http://www.fmglobal.com/page.aspx?id=04010200 Free access with registration

Ammonium Nitrate Handling, (2013). Bunn Fertiliser, Ltd.

Chemical Advisory: Safe Storage, Handling, and Management of Ammonium Nitrate                    August 2013

Ammonium Nitrate, Industrial Grade, Technical Information. (2011) Dyno Nobel Inc.
http://www.dynonobel.com/files/2010/04/lAmmonium  Nitrate LomoDonora-lndustrial.pdf

Ammonium Nitrate, Nutrient Source Specific (NSS) Fact Sheet, No. 22 International Plant Nutrition
Institute, Norcross, GA
http://www.ipni. net/publication/nss.nsf/0/67265AOAC9302CC5852579AF0076927A/$FILE/NSS-

Fire Protection Guide to Hazardous Materials, 14th edition. (2010). National Fire Protection Association,
Quincy, MA.

Guide No. 140 for Oxidizers , Emergency Response Guidebook. 2012. US Dept. of Transportation,
Pipeline and Hazardous Materials Safety Administration.

EPA Chemical Accident Investigation Report, Terra Industries, Inc., Nitrogen Fertilizer Facility, Port Neal,
Iowa. (January, 1996). U.S. Environmental Protection Agency, Region 7, Emergency Response and
Removal Branch, Kansas City, KS. http://www.epa.gov/emergencies/docs/chem/cterra.pdf

West Fertilizer Explosion and Fire. (2013). U.S. Chemical Safety Board

The National Safety Council has a data sheet Ammonium Nitrate Fertilizer, Data Sheet 1-699. (1991) that
discusses the health hazards, properties, and precautions for safe storage and handling of AN fertilizer.

        National Safety Council
        1121 Spring Lake Drive
        Itasca, IL 60143-3201
        Phone: (800) 621-7269 (toll free) or (630)-775-2199 (Library)
        Website: http://www.nsc.org

The Fertilizer Institute (TFI) possesses information on various fertilizer products, including AN, and their

        The Fertilizer Institute
        425 Third Street, SW, Suite 950
        Washington, DC 20024
        Phone: (202) 962-0490
        Website: http://www.tfi.org

ResponsibleAg (RA) is a Fertilizer Code of Practice management system that helps facilities establish
basic Environmental, Health, Safety and Security (EHS&S) performance practices. ResponsibleAg is a
joint venture of the Agricultural Retailers Association (ARA) and The Fertilizer Institute (TFI).  ARA also
has a First Responder Guidance for use by agricultural retailers, LEPCs and local first responders. For
more information, contact:

Chemical Advisory: Safe Storage, Handling, and Management of Ammonium Nitrate                    August 2013
       Agricultural Retailers Association
       1156 15th Street, NW
       Suite 500
       Washington, D.C. 20005
       Phone: 202-457-0825
       Website: www.aradc.org

For more detailed information on the safe handling practices for storage of explosive materials which
may contain AN, please consult the following Safety Library Publications (SLPs) developed by the
Institute of Explosive Makers (IME).

       Construction Guide for Storage Magazines, IME SLP No. 1 (September 2006).
       The American Table of Distances, IME SLP No. 2 . (October 2011).
       Suggested Code of Regulations for the Manufacture, Transportation, Storage, Sale, Possession,
       and Use of Explosive Materials, IME SLP No. 3. (October 2009).
       Handbook for the Transportation and Distribution of Explosive Material,  IME SLP No. 14.  (April
       Safety in the Transportation, Storage and Use of Explosive Materials,  IME SLP No. 17 (October
       Recommendations for the Transportation of Explosives, Division 1.5, Ammonium Nitrate
       Emulsions, Division 5.1, Combustible Liquids, Class 3, and Corrosives, and Liquids, Class 8 in Bulk
       Packaging, IME SLP No. 23. (October 2011).
       Explosives Manufacturing and Processing Guide to Safety Training, IME SLP No. 25.  (May 2011).

       SLPs are  available at http://www.ime.org/ecommerce/products.php7category id=13

       Institute of Makers of Explosives (IME)
       1120 Nineteenth St. N.W. Suite 310
       Washington, DC 20036-3605
       Website: www.ime.org

SAFEX International is an industry group whose members manufacture civil or military explosives or
technical grade ammonium  nitrate (TGAN). TGAN is generally in the form of porous prills and is used in
the manufacture of commercial explosives. SAFEX has published a guide for safe storage of TGAN listed
below that is available to its members.  https://www.safex-international.org/  index.php

       Good Practice Guide: Storage of Solid Technical Grade Ammonium Nitrate. (March 2011).
       International Working Group on Ammonium Nitrate, SAFEX International. SAFEX Good Explosive
       Practice Series,  GPG 02 rev. 1

Chemical Advisory: Safe Storage, Handling, and Management of Ammonium Nitrate                   August 2013


 Statutes and regulations applicable to the manufacture of or processes involving AN, are listed below.

Clean Air Act Accident Prevention- General Duty (EPA)

Section 112(r) of the Clean Air Act (CAA) focuses on prevention of chemical accidents. Under this
provision of the CAA, all facilities with regulated substances or other extremely hazardous substances
have a general duty to  prevent and mitigate accidental releases.  Under Section 112(r)(l), the general
duty is :

       to  identify hazards ...using appropriate hazard assessment techniques, to design and maintain a
       safe facility taking such steps as are necessary to prevent releases, and to minimize the
       consequences of accidental releases which do occur.

This general duty applies to facilities producing, processing, handling or storing extremely hazardous
substances. While not a regulated substance, AN may be considered extremely hazardous under certain

Clean Air Act- Risk Management Program (EPA) and Process Safety Management (OSHA)

In 1990, amendments to the CAA authorized the EPA's Risk Management Program (RMP) Rule (40 CFR
Part 68) under section 112(r), and required the Occupational Health and Safety Administration (OSHA)
to issue the Process Safety Management Program  (PSM) rule. Both rules serve to prevent chemical
accidents.  The RMP  focuses on prevention and mitigation of accidental releases of listed toxic and
flammable substances.  Requirements under the RMP rule include development of a hazard assessment,
a prevention program,  and an emergency response program. While AN is not a listed substance subject
to the RMP, chemicals used in the production of AN are included on the RMP list, making the process
producing AN potentially subject to the RMP.  Certain processes using AN may also involve RMP listed
substances. For more information about RMP regulations, see

OSHA's Process Safety Management (PSM) Standard establishes requirements intended to protect
employees by preventing or minimizing the consequences of chemical accidents involving highly
hazardous chemicals (29 CFR 1910.119). Although AN is not covered by the PSM standard, the
production or use of AN may involve PSM listed chemicals in excess of thresholds. Manufacture of
explosives, which may involve AN, is also covered by the PSM standard. For more information about
OSHA's PSM standard see https://www.osha.gov/SLTC/processsafetvmanagement/index.html

Emergency Planning and Community Right-to-Know Act (EPA)

The Emergency Planning and Community Right-to-Know Act (EPCRA), requires information on the
presence of hazardous chemicals above designated threshold quantities at regulated facilities be
provided to state and local emergency planning authorities. This information facilitates development of
emergency response plans required by section 303 of EPCRA, enhances community awareness of

Chemical Advisory: Safe Storage, Handling, and Management of Ammonium Nitrate                   August 2013

chemical hazards and help first responders to respond to chemical accidents. The chemicals covered
under these requirements are a specific list of chemicals known as Extremely Hazardous Substances
(EHSs) found at 40 CFR Part 355 Appendices A and B and any chemicals that meet the criteria as
hazardous chemicals under OSHA's Hazard Communication Standard. AN is not an EHS but is considered
a hazardous chemical (oxidizer) and therefore subject to the EPCRA provisions described below.

Section 311 of EPCRA requires facilities to submit Safety Data Sheets for the EHSs and hazardous
chemicals to their State or Tribal Emergency Response Commission (SERC or TERC), Local Emergency
Planning Committee (LEPC) and local fire department. Section 312 requires facilities to submit annually
to their SERC or TERC, LEPC, and local fire department, Hazardous Chemical Inventory forms for these
chemicals. The SDS provides the chemical's hazard information and emergency response guidelines and
the Hazardous Chemical Inventory form provides the quantity, storage types and locations of the
chemical at their facility.  Regulations covering these requirements are found at 40 CFR Part 370.

Section 311(e)(5) of EPCRA does not include the following as a  hazardous chemical: any substance used
in routine agricultural operations or a fertilizer held for sale by a retailer to  the ultimate customer.  At
fertilizer distributors, AN  is commonly blended with other chemicals to produce a fertilizer mix
according to customer specifications. Any AN that is mixed or formulated with other chemicals by
facilities is not covered by the Section 311(e)(5) exemption. The exemption was intended to apply only
to retailers of the substance, not to manufacturers and wholesalers - who typically have large quantities
of fertilizers, and may use and manufacture a wide range of chemical compounds. These manufacturers
and wholesalers can present significant risks that need to be addressed by emergency response
authorities. For more information about EPCRA hazardous chemical reporting, see

Environmental Protection Agency (EPA)
Phone: (800) 424-9346 or (703) 412-9810
Website: http://www.epa.gov

Explosives and Blasting Agents Standards (OSHA)

In addition to the PSM program described above, the Occupational Safety and Health Administration
(OSHA) regulates the manufacture, keeping, having, storage, sale, transportation, and use of explosives
and blasting agents under its Occupational Safety and Health Standards for explosives and blasting
agents (29 CFR 1910.109). Blasting agents are frequently formulated with AN.  For more information
about OSHA's standards covering explosives and blasting agents, including ammonium nitrate and
storage of all grades of ammonium nitrate, see
https://www.osha.gov/pls/oshaweb/owadisp.show document?p id=9755&p table=STANDARDS

Hazard Communication Standard (OSHA)

OSHA's Hazard Communication Standard (HCS) at 29 CFR 1910.1200 requires chemical manufacturers
and importers to evaluate the hazards of the chemicals they produce or import, and prepare labels and
Safety Data Sheets (SDS) to convey the hazard information to their downstream customers.  All


Chemical Advisory: Safe Storage, Handling, and Management of Ammonium Nitrate                    August 2013

employers with hazardous chemicals in their workplaces must have labels and safety data sheets for
their exposed workers, and train them to handle the chemicals appropriately.  AN is a hazardous
chemical covered under the HCS. The HCS is now aligned with the Globally Harmonized System of
Classification and Labeling of Chemicals (GHS).  Employers are required to train workers by December 1,
2013 on the new labels elements and safety data sheets format to facilitate recognition and
understanding. For more information, see http://www.osha.gov/dsg/hazcom/index.html

Occupational Safety and  Health Administration
Phone: (800) 321- OSHA  (6742)
Website: http://www.osha.gov

Chemical Facility Anti-Terrorism Standards (DHS)

The Department of Homeland Security (DHS)'s Chemical Facility Anti-Terrorism Standards (CFATS)
program applies to facilities that possess threshold quantities of certain types of ammonium nitrate.
Facilities in possession of Chemicals of Interest (listed in 6 CFR Part 27 Appendix A) exceeding specific
threshold quantities are  required to complete a "Top-Screen" questionnaire to identify the types and
quantities of Chemicals of Interest the facility possesses.  For ammonium nitrate at any concentration
(with more than 0.2% combustible substances, including any organic substance calculated as carbon, to
the exclusion of any other added substance) the Screening Threshold Quantity for risk of release is 5,000
pounds and for risk of theft is 400 pounds. This same form of ammonium nitrate is also classified by
DOT as a Division 1.1  explosive. For solid ammonium nitrate,  with a minimum concentration of 33% or
greater and a nitrogen concentration of 23% nitrogen or greater, the Screening Threshold Quantity for
risk of theft is 2,000 pounds.  The CFATS program, first established under Section 550 of the 2007 DHS
Appropriations Act, identifies and regulates high-risk chemical facilities to ensure they have security
measures in place to  reduce the risks associated with these chemicals. CFATS regulations are found in 6
CFR Part 27.

Based on the Top-Screen, if DHS initially determines the facility to be high-risk, the facility must
complete and submit a Security Vulnerability Assessment, which  is then reviewed by DHS to make a final
determination on whether the facility is high-risk. Facilities receiving a final high-risk determination
must develop and submit for DHS's review, a Site Security Plan (SSP), or alternatively, an Alternative
Security Program, that describes the specific  security measures the facility will utilize to meet the 18
applicable risk-based  performance standards under CFATS. The agency must then conduct an inspection
to help determine whether or not the facility's SSP should be approved. For more information about
CFATS program, see http://www.dhs.gov/chemical-facility-anti-terrorism-standards

Hazardous Materials (DOT)

The Department of Transportation (DOT) regulates transportation of AN under its Hazardous Materials

The following forms of ammonium nitrate are listing in the DOT Hazardous Materials Table (49 CFR
172.101) with their Hazard Class or Division:


Chemical Advisory: Safe Storage, Handling, and Management of Ammonium Nitrate                    August 2013
Ammonium nitrate based fertilizer, 5.1
Ammonium nitrate based fertilizer, 9  (when transported by vessel or aircraft)
Ammonium nitrate emulsion or Ammonium nitrate suspension or Ammonium nitrate gel, intermediate
for blasting explosives, 5.1
Ammonium nitrate-fuel oil mixture containing only prilled ammonium nitrate and fuel oil, 1.5D
Ammonium nitrate, liquid (hot concentrated solution), 5.1
Ammonium nitrate, with more than 0.2 percent combustible substances, including any organic
substance calculated as carbon, to the exclusion of any other added substance, 1.1D
Ammonium nitrate, with not more than 0.2% total combustible material, including any organic
substance, calculated as carbon to the exclusion of any other added substance, 5.1

 Explanation of Hazard Class numbers:
1.1 - Explosives (with a mass explosion hazard)  A mass explosion is one which affects almost the entire
load instantaneously.
1.5 - Very insensitive explosives; blasting agents
5.1 - Oxidizer
 9 - Miscellaneous Hazard Material

DOT also requires security plans for persons offering for transportation or transporting any quantity of a
Division 1.1 or 1.5 material containing ammonium nitrate or large bulk quantities (greater than 6,614 Ibs
or 792 gals) of ammonium nitrate, ammonium nitrate fertilizers, or ammonium nitrate emulsions,
suspensions, or gels. The security plan must conform to requirements in 49 CFR 172.800.

Department of Transportation
Phone: (202) 366-5580 - Public Information
Website: http://www.dot.gov

Explosives Regulations (ATF)

The Bureau of Alcohol, Tobacco, Firearms, and Explosives (ATF) of the Department of the Justice
regulates the importation, manufacture, distribution, and storage of explosive materials including
blasting agents and other explosive materials containing AN. ATF's explosives regulations,  27 CFR Part
555, can be located at http://www.atf.gov/regulations-rulings/regulations/index.html

Bureau of Alcohol, Tobacco, Firearms, and Explosives
Website: http://atf.gov

For More Information, Contact:

The Superfund, TRI, EPCRA, Risk Management Program, and Oil Information Center
(800) 424-9346 or (703) 412-9810
TDD (800) 553-7672 or (703) 412-3323