1.2.
General
1.2.1. Where the provisions of these Rules
impose undue hardship or where the literal adherence to the provisions fails to
provide adequate safety, the Commissioner may permit deviation from the
Rules.
1.2.2. The term "anhydrous
ammonia" as used in these Rules refers to the compound, formed by a combination
of two gaseous elements, nitrogen and hydrogen, in the proportion of one part
nitrogen to three parts hydrogen by volume. Anhydrous ammonia may be in either
gaseous or liquid form. It is not to be confused with aqua ammonia which is a
solution of ammonia gas in water. Whenever the term "ammonia" appears in these
Rules, it means anhydrous ammonia.
1.2.3. It is important that personnel
understand the properties of this gas and that they be thoroughly trained in
safe practices for its storage and handling. Some of the important physical
properties of ammonia are listed in 1.2.5.
1.2.4. Gaseous ammonia liquefies under
pressure at ambient temperature. Advantage of this characteristic is taken by
industry and for convenience this commodity is usually shipped and stored under
pressure as a liquid. When refrigerated to or below its normal boiling point
(-28ºF) it may be shipped and stored as a liquid at atmospheric
pressure.
1.2.5. Physical
Properties of Ammonia:
|
Molecular symbol
|
NH3
|
|
Molecular weight
|
17.032
|
|
Boiling point at one atmosphere*
|
-28ºF
|
|
Melting point at one atmosphere*
|
-107.9ºF
|
|
Critical temperature
|
271.4ºF
|
|
Critical pressure
|
1657 psia.
|
|
Latent heat at-28ºF and one atmosphere*
|
589.3 Btu per pound
|
|
Relative density of vapor compared to dry air at
32ºF and one atmosphere*
|
0.5970
|
|
Vapor density at-28ºF and one
atmosphere*
|
0.05555 lb. per cu ft
|
|
Specific gravity of liquid at-28ºF compared to
water at 39.2ºF
|
0.6819
|
|
Liquid density at-28ºF and one
atmosphere*
|
42.57 lb. per cu ft
|
|
Specific volume of vapor at 32ºF and one
atmosphere*
|
20.78 cu ft per pound
|
|
Flammable limits by volume in air at atmospheric
pressure
|
16% to 25%
|
|
Ignition Temperature (in a standard quartz
container)
|
1562ºF
|
|
Specific Heat, Gas, 15ºC, one atm at constant
pressure, Cp
|
0.5232 Btu/lb. ºF
|
|
at constant volume, Cv
|
0.3995 Btu/lb. ºF
|
*One atmosphere = 14.7 psia.
1.2.6. Experience has shown that ammonia is
extremely hard to ignite and under normal conditions is a very stable compound.
It takes temperatures of 840-980ºF to cause it to dissociate slightly at
atmospheric pressure. The flammable limits at atmospheric pressure are 16% to
25% by volume of ammonia in air. Experiments conducted by a nationally
recognized laboratory indicated that an ammonia-air mixture in a standard
quartz test container does not ignite below 1562ºF. Ammonia is classified
by the United States Department of Transportation and the United States Coast
Guard as a non-flammable compressed gas for the purpose of
transportation.
1.2.7. Ammonia
should be handled only by properly trained personnel. In no case should ammonia
be used in conjunction with chemicals unless the possible reactions have first
been adequately investigated. Under some circumstances ammonia and ammonium
compounds can form explosive products with other chemicals.
1.2.8. Ammonia gas irritates the skin and
mucous membrane. Its odor is detectable by most people. Since ammonia gas is
lighter than air, adequate ventilation is the best means of preventing any
accumulation.
1.2.9. Zinc, copper
and copper base alloys such as brass are subject to rapid destructive action by
ammonia in the presence of water.
1.3.
Standards Incorporated by
Reference
1.3.1. The following
standards are hereby incorporated by reference in these Rules:
1.3.1.1. U.S. Department of Transportation
(DOT) Regulations referring to Hazardous Materials Regulations of the
Department of Transportation, including specifications for shipping containers,
Code of Federal Regulations, 49 CFR parts
171 to
190, October 1, 2011 edition. This
rule does not adopt any later amendments or editions.
1.3.1.2. American Society of Mechanical
Engineers (ASME) Boiler and Pressure Vessel Code parts UW-1 though UW-65,
Section VIII, Division 1, Titled "Part UW: Requirements for Pressure Vessels
Fabricated by Welding," 2015 edition. This rule does not adopt any later
amendments or editions.
1.3.1.3.
Unfired Pressure Vessel Code of the American Society of Mechanical Engineers
(Sections VIII of the ASME Boiler Construction Code), 1952, 1956, 1959, 1962,
1965, 1968, 1971, 1978, 1983, 1989, 1996, 1997, 2001, 2007, 2008, 2010 and 2015
editions. This rules does not adopt any later amendments or editions.
1.3.1.4. National Electrical Code, NFPA 70
(ANSI-C1), for Class I, Group D locations, 2014 edition. This rule does not
adopt any later amendments or editions.
1.3.1.5. American Petroleum Institute, API
Standard 620, Twelfth edition, 2013. This rule does not adopt any later
amendments or editions.
1.3.1.6.
Portable U.S. Department of Transportation (DOT) Containers, Code of Federal
Regulations 49 CFR
173.32 october 1, 2011 edition. This rule
does not adopt any later amendments or editions.
1.3.1.7. Compressed Gas Association
Publication P-1, 2015 edition. This rule does not adopt any later amendments or
editions.
1.3.1.8. U.S. Department
of Transportation (DOT) Regulation referring to systems utilizing cylinders,
portable tanks (DOT-51), Code of Federal Regulations 49 CFR Part
173.32 ,
October 1, 2011 edition. This rule does not adopt any later amendments or
editions.
1.3.1.9. U.S. Department
of Transportation (DOT) Regulations referring to systems utilizing "Ton
Containers" (DOT-106A, DOT-110A) Code of Federal Regulations
49 CFR Parts
179.300-179.301, October 1, 2011 edition.
This rule does not adopt any later amendments or editions.
1.3.1.10. The American National Standards
Institute's Method of Marking Portable Compressed Gas Containers to Identify
the Material Contained, ANSI Z48.1, 1954 edition. This rule does not adopt any
later amendments or editions.
1.3.1.11. U.S. Department of Transportation
(DOT) Regulations referring to safety relief device requirements, Code of
Federal Regulations 49 CFR Part
173.315 , October 1, 2011 edition. This rule
does not adopt any later amendments or editions.
1.3.2. A copy of the Official Publications of
the above incorporated Standards shall be kept on file at the Colorado
Department of Agriculture, located at 305 Interlocken Parkway, Broomfield
Colorado 80021, and shall be open to public inspection, and available for
copying, during normal business hours.
A copy of the official publication of the U.S. Department of
Transportation (DOT) regulations shall also be kept at the U.S. Department of
Transportation, 1200 New Jersey Avenue SE, Washington D.C. 20590 and is
available online at: transportation.gov/regulations.
A copy of the official publication of the American Society of
Mechanical Engineers shall be kept on file at the Colorado Department of
Agriculture, located at 305 Interlocken Parkway, Broomfield Colorado 80021, and
shall be open to public inspection, and available for copying, during normal
business hours. A copy of the official publication of the American Society of
Mechanical Engineers shall also be kept at the ASME Headquarters, Two Park
Avenue, New York NY 10016-5990 and is available online at: ASME.org
A copy of the official publication of The National Electrical
Code shall be kept on file at the Colorado Department of Agriculture, located
at 305 Interlocken Parkway, Broomfield Colorado 80021, and shall be open to
public inspection, and available for copying, during normal business hours. A
copy of the official publication of the National Electrical Code shall also be
kept at The National Fire Protection Association, 1 Batterymarch Park, Quincy
Massachusetts 02169-7471 and is available online at: NFPA.org
A copy of the American Petroleum Institute Standards shall be
kept on file at the Colorado Department of Agriculture, located at 305
Interlocken Parkway, Broomfield Colorado 80021, and shall be open to public
inspection, and available for copying, during normal business hours. A copy of
the official publication of the American Petroleum Institute Standards shall
also be kept at the American Petroleum Institute, 200 Massachusetts Avenue NW,
suite 1100, Washington D.C., 20001-5571 and is available online at:
API.org.
A copy of the Compressed Gas Association Publication shall be
kept on file at the Colorado Department of Agriculture, located at 305
Interlocken Parkway, Broomfield Colorado 80021, and shall be open to public
inspection, and available for copying, during normal business hours. A copy of
the official publication of the Compressed Gas Association shall also be kept
at 14501 George Carter Way, suite 103, Chantilly, VA 20151 and is available
online at: CGANET.com.
A copy of the American National Standards Institute's
standards Publication shall be kept on file at the Colorado Department of
Agriculture, located at 305 Interlocken Parkway, Broomfield Colorado 80021, and
shall be open to public inspection, and available for copying, during normal
business hours. A copy of the official publication of the American National
Standards Institute's Standards shall also be kept at ANSI headquarters, 1899 L
Street NW, Washington D.C. 20036 and is available online at: ANSI.org.
1.4.
Definitions
The following definitions are used for the purpose of these
Rules:
1.4.1. "Approved" means:
1.4.1.1. Listed by a recognized testing
laboratory, or
1.4.1.2. Recommended
by the manufacturer as suitable for use with anhydrous ammonia and so marked,
or
1.4.1.3. Accepted by the
Commissioner.
1.4.2.
"Appurtenance" refers to all devices such as safety relief devices, liquid
level gauging devices, valves, pressure gauges, fittings, metering or
dispensing devices.
1.4.3. "ASME"
means American Society of Mechanical Engineers.
1.4.4. "Backflow check valve" means a device
designed to prevent ammonia from flowing in the wrong direction within a pipe
or tube.
1.4.5. "Capacity" refers
to the total volume of the container measured in U.S. gallons, unless otherwise
specified.
1.4.6. "Chemical-splash
goggles" and "splash proof goggles" means flexible-fitting chemical-protective
goggles, with a hooded, indirect ventilation system that provides protection to
the eyes and eye sockets from the splash of hazardous liquids. This term shall
not include direct vented goggles.
1.4.7. "Cylinder" means a container of 1000
pounds water capacity or less.
1.4.8. The "Code" refers to the Unfired
Pressure Vessel Code of the American Society of Mechanical Engineers (Section
VIII of the ASME Boiler Construction Code), 2015 edition.
1.4.9. "Container" includes all vessels,
tanks, cylinders or spheres used for transportation, storage or application of
anhydrous ammonia.
1.4.10. "Data
plate" means a piece of non-corroding metal permanently attached by the
manufacturer to the surface of a container.
1.4.11. "Densely populated area" means any
location with either one or more multifamily housing units or eight or more
single-family dwellings located within a quarter section.
1.4.12. "Design Pressure" is identical to the
term "Maximum Allowable Working Pressure" used in the Code.
1.4.13. "Emergency shutoff valve" means a
valve that stops the flow of product by spring closure, gravity, or pressure
and can be activated by an outside means including a cable pull, hose pull, air
assists, electrical closure or back pressure.
1.4.14. "Excess-flow valve" means a device
placed in a line that is designed to close when the flow of vapor or liquid
flowing through the line exceeds the amount for which the valve is
rated.
1.4.15. An "Implement of
Husbandry" is a farm wagon-type tank vehicle of not over 3000 gallons capacity,
used as a field storage "nurse tank" supplying the fertilizer to a field
applicator and moved on highways for bringing the fertilizer from a local
source of supply to farms or fields or from one farm or field to
another.
1.4.16. "Filling Density"
means the percent ratio of the weight of the gas in a container to the weight
of water at 60ºF that the container will hold. For determining the water
capacity of the tank in pounds, the weight of a gallon (231 cubic inches) of
water at 60ºF in air shall be 8.32828 pounds.
1.4.17. "Gas" refers to anhydrous ammonia in
either the gaseous or liquefied state.
1.4.18. "DOT Regulations" refer to Hazardous
Materials Regulations of the U.S. Department of Transportation (Title
49-Transportation, Code of Federal Regulations, Parts 171 to 190), including
Specifications for Shipping Containers.
1.4.19. "Mobile container" means any
container that is not installed as a permanent storage container.
1.4.20. "Non-code welding" means welding that
does not comply with parts UW-1 through UW-65 of the ASME Boiler and Pressure
Vessel Code, Sections VIII, Division 1, Titles "Parts UW: Requirements for
Pressure Vessels Fabricated by Welding," 2015 edition.
1.4.21. "Permanent storage container" means a
stationary container having a volume of at least 3,000 water gallons.
1.4.22. "Permanent storage facility" means a
site that includes one or more permanent storage containers and their
connections and appurtenances.
1.4.23. "Place of public assembly" means any
building, structure or facility established to accommodate groups of people for
commercial, civic, political, religious, recreational, educational, or other
purposes. This term shall include buildings or structures used for medical
care, including hospitals, assisted care facilities, and prisons.
1.4.24. "Systems" as used in these Rules
refers to an assembly of equipment consisting essentially of the container or
containers, appurtenances, pumps, compressors, and interconnecting
piping.
1.4.25. The abbreviations
"psig" and "psia" refer to pounds per square inch gauge and pounds per square
inch absolute, respectively.
1.4.26. The terms "charging" and "filling"
are used interchangeably and have the same meaning.
1.4.27. "Trailer" as used in these Rules
refers to every vehicle designed for carrying persons or property while being
drawn by a motor vehicle and so constructed that no part of its weight except
the towing device rests upon the towing vehicle.
1.4.28. "Tank Motor Vehicle" means any motor
vehicle designed or used for the transportation of anhydrous ammonia in any
tank designed to be permanently attached to any motor vehicle or any container
not permanently attached to any motor vehicle which by reason of its size,
construction or attachment to any motor vehicle must be loaded and/or unloaded
without being removed from the motor vehicle.
1.4.29. "Semi-trailer" refers to every
vehicle designed for carrying persons or property while being drawn by a motor
vehicle and so constructed that some part of its weight and that of its load
rests upon or is carried by another vehicle.
1.4.30. "Safety Relief Valve" refers to an
automatic spring loaded or equivalent type pressure activated device for gas or
vapor service characterized by pop action upon opening, sometimes referred to
as a pop valve.
1.4.31.
"Hydrostatic Relief Valve" refers to an automatic pressure activated valve for
liquid service characterized by throttle or slow weep opening (non-pop
action).
