CNG Fuel Inspector Resource Package
Consists of CSA/ANSI NGV 1-2017, Compressed Natural Gas Vehicle (NGV) Fueling Connection Devices; ANSI PRD 1-2013, Pressure relief devices for natural gas vehicle (NGV) fuel containers; CSA/ANSI NGV 2:19, Compressed natural gas vehicle fuel containers; ANSI NGV 3.1-2014/CSA 12.3-2014, Fuel system components for compressed natural gas powered vehicles; SPE-2.1 SERIES-18, Best practices for defueling, decommissioning, and disposal of compressed natural gas vehicle fuel containers and liquefied natural gas vehicle fuel tanks and CSA NGV 6.1-2018, Compressed Natural Gas (CNG) fuel storage and delivery systems for road vehicles
Product Details
Overview
The CNG Fuel Inspector Resource Package is a collection of relevant CSA Natural Gas Vehicle (NGV) standards including connection devices, pressure relief devices and fuel containers.
CSA/ANSI NGV 1-2017 - Compressed Natural Gas Vehicle (NGV) Fueling Connection Devices
This standard is being developed for agencies in North America to use for examination, testing and certification of compressed Natural Gas Vehicle (NGV) fueling nozzles and receptacles used in NGV fueling systems, and not to the systems themselves. The American Gas Association (A.G.A.) Requirements for Natural Gas Refueling Connection Devices (No. 1-90) and Canadian Gas Association Certification Requirement for NGV Nozzles and Receptacles (Draft CR 90-005) provided a basis for this standard.
This standard applies to newly produced compressed Natural Gas Vehicle (NGV) fueling connection devices constructed entirely of new, unused parts and materials. It covers receptacle and protective caps (mounted on vehicle), nozzles, and three-way valves. It applies to devices with standardized mating components. In addition, it applies to devices which both prevent natural gas vehicles from being fueled by dispenser stations with service pressures higher than the vehicle, and allow natural gas vehicles to be fueled by dispenser stations with service pressures equal to or lower than the vehicle fuel system service pressure.
ANSI PRD 1-2013 - Pressure Relief Devices for Natural Gas Vehicle (NGV) Fuel Containers
This standard establishes minimum requirements for pressure relief devices intended for use on fuel containers that comply with ANSI/CSA NGV2, Compressed Natural Gas Vehicle (NGV) Fuel Containers, FMVSS 304, Federal Motor Vehicle Safety Standards, 49 CFR Part 571.304, Compressed Natural Gas Fuel Container Integrity, CSA B51, Part 2, High Pressure Cylinders for On-Board Storage of Natural Gas as a Fuel for Automotive Vehicles and/or ISO 11439 Gas Cylinders - High Pressure Cylinders for the Onboard Storage of Natural Gas as a Fuel for Automotive Vehicles.
The standard represents a standard for safe operation, substantial and durable construction and performance testing of pressure relief devices (PRD) for natural gas vehicle (NGV) fuel containers, for the on-board storage of compressed natural gas for vehicle operation within specified limitations. It is based on proven engineering principles, research and the combined expertise of gas utilities, manufacturers, users, and others having specialized experience.
ANSI NGV 3.1-2014/CSA 12.3-2014 - Fuel System Components for Compressed Natural Gas Powered Vehicles
First published in 1995, this is the third edition of ANSI NGV 3.1 - CSA 12.3, Fuel System Components for Compressed Natural Gas Powered Vehicles. It establishes requirements for newly produced compressed natural gas fuel system components, intended for use on natural gas powered vehicles.
Highlights of the standard includes detailed and informative Annexes, a clause that list all fuel system components, and an emphasis on the pressure containment, performance and safety characteristics of specified components. The standard also applies to components downstream of the first stage of pressure reduction with a working pressure designated by the manufacturer in kPa (psi). In the case of conflict between this standard and Federal, Provincial, State or local requirements, the government requirements are to take precedence.
EXP2.1-16 - Best Practice for Defueling, Decommissioning, and Disposal of Compressed Natural Gas Vehicle Fuel Containers
CNG cylinders are pressurized, which means users must take special precautions when it comes to proper maintenance, replacement and disposal. A cylinder can be safely used until its expiration date as marked on the cylinder label provided there is no damage, corrosion, or other issues with the tank. Keeping cylinders in use after the expiration date or operating damaged tanks can have serious safety consequences.
CSA Group has developed a best practices document - CSA EXP2.1 Best Practice Defueling, Decommissioning, and Disposal of Compressed Natural Gas Vehicle Fuel Containers to help address the safety issues associated with removing CNG fuel containers from circulation.
CSA EXP2.1 is available in PDF or new ePub format - accessible on mobile devices and additional features such as bookmarking and the ability to email short sections.
CSA/ANSI NGV 2-2016 - Compressed Natural Gas Vehicle Fuel Containers
This standard provides guidance for safe operation, substantial and durable construction and performance testing of containers for the on-board storage of compressed natural gas for vehicle operation within specified limitations. It is based on engineering principles, research and the combined expertise of gas utilities, manufacturers, users, and others having specialized experience.
The standard contains requirements for the material, design, manufacture and testing of serially produced, refillable Type NGV 2 containers intended only for the storage of compressed natural gas for vehicle operation. Users of this American National Standard are advised that the devices/products/activities within its scope may be subject to regulation at the federal, state, or local levels. Users are strongly urged to investigate this possibility through appropriate channels. In the event of a conflict with this standard, the federal, state, or local regulations should be followed.
CSA/ANSI NGV 6.1-2018 - Compressed natural gas (CNG) fuel storage and delivery systems for road vehicles
This Standard applies to the design, installation, inspection, repair, and maintenance of a fuel storage and delivery system installed in an on road vehicle for use with compressed natural gas (CNG). This includes a fuel system on a self-propelled vehicle for the provision of motive power.
CSA/ANSI NGV 1-2017 - Compressed Natural Gas Vehicle (NGV) Fueling Connection Devices
Preface
This is the third edition of CSA/ANSI NGV 1, Compressed natural gas vehicle (NGV) fueling connection devices. It supersedes the previous editions published in 2006 and 1998.
P36HD nozzles designed in accordance with this Standard will not be compatible with existing P36 heavy duty applications using C200 (ISO 14469) receptacles, equivalent to P30HD (see Figure 6).
Scope
1.1
This Standard applies to newly produced compressed Natural Gas Vehicle (NGV) fueling connection devices, hereinafter referred to as devices, constructed entirely of new, unused parts and materials. NGV fueling connection devices consist of the following components, as applicable:
a) receptacle and protective cap (mounted on vehicle) (see Clause 4.4)
b) nozzle (see Clause 4.2); and
c) three-way valve (external to nozzle and mounted in the fuel dispenser system) (see Clause 4.5).
1.2
This Standard applies to devices that have a service pressure of either 8300 kPa (1200 psi), 16 500 kPa (2400 psi), 20 700 kPa (3000 psi), or 24 800 kPa (3600 psi), hereinafter referred to in this Standard as the following (see Clause 4.8.3 c)):
P12 - 8300 kPa (1200 psi)
P24 - 16 500 kPa (2400 psi)
P30 and P30HD - 20 700 kPa (3000 psi)
P36 and P36HD - 24 800 kPa (3600 psi)
The HD suffix designates a larger geometry version to allow higher flow rates associated with fueling larger heavy duty applications.
1.3
This Standard applies to devices with standardized mating components (see Clauses 4.4.6 and 4.6).
1.4
This Standard applies to devices that:
a) prevent natural gas vehicles from being fueled by a dispenser with service pressures higher than the vehicle it was designed for;
b) allow natural gas vehicles to be fueled by a dispenser with service pressures equal to or lower than the vehicle fuel system service pressure; and
c) prevent light duty natural gas vehicles from being fueled by a heavy duty dispenser.
1.5
This Standard does not apply to repaired or rebuilt nozzles.
1.6
All references to psi or kPa throughout this Standard are to be considered gauge pressures unless otherwise specified.
1.7 Units of measure
This Standard contains SI (metric) units with corresponding yard/pound quantities, the purpose being to allow the Standard to be used in yard/pound units. IEEE/ASTM SI 10, American National Standard for Metric Practice, or ISO 80000-1:2009 Quantities and units - Part 1: General, is used as a guide in making conversion.) If a value for a measurement and a corresponding value in other units are stated, the first stated value is to be regarded as the requirement. The given corresponding value may be approximate. If a value for a measurement and a corresponding value in other units, are both specified as a quoted marking requirement, the first stated unit, or both are to be provided.
1.8 Terminology
In this Standard, shall is used to express a requirement, i.e., a provision that the user shall satisfy in order to comply with the standard; should is used to express a recommendation or that which is advised but not required; and may is used to express an option or that which is permissible within the limits of the standard.
Notes accompanying clauses do not include requirements or alternative requirements; the purpose of a note accompanying a clause is to separate from the text explanatory or informative material.
Notes to tables and figures are considered part of the table or figure and may be written as requirements.
Annexes are designated normative (mandatory) or informative (non-mandatory) to define their application.
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ANSI PRD 1-2013 - Pressure relief devices for natural gas vehicle (NGV) fuel containers
Preface
This publication represents a standard for safe operation, substantial and durable construction and performance testing of pressure relief devices (PRD) for natural gas vehicle (NGV) fuel containers, for the on-board storage of compressed natural gas for vehicle operation within limitations given below and in the scope of this standard.
This standard is based on proven engineering principles, research and the combined expertise of gas utilities, manufacturers, users, and others having specialized experience.
Nothing in this standard is to be considered in any way as indicating a measure of quality beyond compliance with the provisions it contains. It is designed to allow compliance of products which may exceed that specified in the provisions herein. In its preparation, full recognition has been given to possibilities of improvement through ingenuity of design. This standard is subject to revision as further experience and investigation may show it is necessary and desirable.
This standard does not apply to fuel system components that will be incorporated during original manufacture of motor vehicles which comply with Federal Motor Vehicle Safety Standards (FMVSS) or Canadian Motor Vehicle Safety Standards (CMVSS) for Natural Gas Powered Vehicles.
Scope
1.1
This standard establishes minimum requirements for pressure relief devices intended for use on fuel containers that comply with ANSI/CSA NGV2, Compressed Natural Gas Vehicle (NGV) Fuel Containers, FMVSS 304, Federal Motor Vehicle Safety Standards, 49 CFR Part 571.304, Compressed Natural Gas Fuel Container Integrity, CSA B51, Part 2, High Pressure Cylinders for On-Board Storage of Natural Gas as a Fuel for Automotive Vehicles and/or ISO 11439 Gas Cylinders - High Pressure Cylinders for the Onboard Storage of Natural Gas as a Fuel for Automotive Vehicles.
Pressure relief devices may be of any design or manufacturing method that meets the requirements of this standard.
The construction of pressure relief devices, whether specifically covered in this standard or not, shall be in accordance with reasonable concepts of safety, performance and durability.
This standard does not apply to reseating or resealing devices.
1.1.1
Pressure relief devices designed to comply with this standard are expected to be used with natural gas fuel containing no more than two percent hydrogen by volume.
Resistance to chloride stress corrosion cracking shall be taken under consideration if selecting stainless steel materials. Resistance to stress corrosion cracking and sustained load cracking shall be taken under consideration if selecting aluminum materials. Resistance to sulfide stress cracking shall be taken under consideration if selecting steel materials..
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ANSI NGV 3.1-2014/CSA 12.3-2014 - Fuel system components for compressed natural gas powered vehicles
Preface
This is the third edition of ANSI NGV 3.1 - CSA 12.3, Fuel system components for compressed natural gas powered vehicles. It supersedes the previous editions published in 2012 and 1995.
Scope
1.1
This Standard establishes requirements for newly produced compressed natural gas fuel system components, intended for use on natural gas powered vehicles, as listed in Table 1, below:
Table 1 - Fuel system components - (See Clauses 1.1 and 1.5.)
- Check valve
- Manual valve
- Manual container valve
- Automatic valve
- Gas injector
- Pressure indicator
- Pressure regulator
- Gas flow adjuster
- Gas/air mixer
- Pressure relief valve
- Pressure relief device
- Excess flow valve
- Gas tight housing and ventilation hoses
- Rigid fuel line
- Flexible fuel line, hoses and assemblies
- Filter
- Fittings
- Discharge line closures
1.2
This Standard applies to devices that have a service pressure of either 16 500 kPa (2 400 psi), 20 700 kPa (3 000 psi), or 24 800 kPa (3 600 psi), hereinafter referred to in this Standard as the following:
P24 - 16 500 kPa (2 400 psi)
P30 - 20 700 kPa (3 000 psi)
P36 - 24 800 kPa (3 600 psi)
The Standard also applies to components downstream of the first stage of pressure reduction with a working pressure designated by the manufacturer in kPa (psi).
1.3
The construction of the noted components whether specifically covered by the various provisions of this Standard or not, is to be in accordance with reasonable concepts of safety, performance and durability.
1.4
All specifications as to construction set forth herein are to be satisfied by the construction actually prescribed or such other construction as will provide at least equivalent performance.
1.5
This Standard emphasizes the pressure containment, performance and safety characteristics of components listed in Table 1.
1.6
It is recognized that other components not specifically covered herein can be examined to meet the criteria of this Standard and tested according to the appropriate functional needs.
1.7
This Standard does not apply to the following:
a) natural gas fuel system components incorporated during the manufacture of motor vehicles originally manufactured in compliance with the Federal Motor Vehicle Safety Standards (FMVSS) for Compressed Natural Gas Fueled Vehicles and the Canadian Motor Vehicle Safety Standard (CMVSS);
b) fuel containers;
c) stationary gas engines;
d) container mounting hardware;
e) electronic fuel management;
f) fueling receptacles; or
g) three way valves.
1.8
In the case of conflict between this Standard and Federal, Provincial, State or local requirements, the government requirements are to take precedence.
1.9
All references to psi throughout this Standard are to be considered gauge pressures, unless otherwise specified.
1.10
This Standard contains SI (metric) units corresponding to the yard/pound quantities, the purpose being to allow the Standard to be used in SI (metric) units. IEEE/ASTM SI I0, American National Standard for Metric Practice, or ISO 80000-1:2009 Quantities and units - Part 1: General, is used as a guide in making metric conversion from yard/pound quantities.) If a value for a measurement and a corresponding value in other units are stated, the first stated value is to be regarded as the requirement. The given corresponding value may be approximate. If a value for a measurement and a corresponding value in other units, are both specified as a quoted marking requirement, the first stated unit, or both are to be provided.
1.11
In this Standard, shall is used to express a requirement, i.e., a provision that the user shall satisfy in order to comply with the standard; should is used to express a recommendation or that which is advised but not required; and may is used to express an option or that which is permissible within the limits of the standard.
Notes accompanying clauses do not include requirements or alternative requirements; the purpose of a note accompanying a clause is to separate from the text explanatory or informative material.
Notes to tables and figures are considered part of the table or figure and may be written as requirements.
Annexes are designated normative (mandatory) or informative (non-mandatory) to define their application.
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SPE-2.1 SERIES-18 - Best practices for defueling, decommissioning, and disposal of compressed natural gas vehicle fuel containers and liquefied natural gas vehicle fuel tanks
Preface
This is the first edition of SPE-2.1 Series, Best practices for defueling, decommissioning, and disposal of compressed natural gas vehicle fuel containers and liquefied natural gas vehicle fuel tanks.
This Series consists of the following Documents:
a) CSA SPE-2.1.1, Best practices for defueling, decommissioning, and disposal of compressed natural gas vehicle fuel containers; and
b) CSA SPE-2.1.2, Best practices for defueling, decommissioning, and disposal of liquefied natural gas vehicle fuel tanks.
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SPE-2.1.1-18 -Best practices for defueling, decommissioning, and disposal of compressed natural gas vehicle fuel containers
Preface
This is the first edition of CSA SPE-2.1.1, Best practices for defueling, decommissioning, and disposal of compressed natural gas vehicle fuel containers. It supersedes CSA EXP2.1, published in 2016.
Scope
1.1 General
This Document contains requirements for the safe removal and disposal of compressed natural gas (CNG) containers from natural gas vehicle (NGV) service when the container
a) has reached its end of life as indicated by the date on the container label;
b) has been condemned in accordance with visual inspection guidelines;
c) is no longer of value to an owner; or
d) has been deemed a public nuisance or imminent hazard by the local authority (abandoned, confiscated, or seized containers).
It is the owner’s responsibility to ensure that the CNG containers on the vehicle are defueled and removed by a qualified agency at the end of the container life (EOL). Once the container has been removed, the custodian of the container is responsible to dispose of the container safely.
Note: Owners should obtain paperwork to document transfer of custody.
1.2 Procedure overview
In general, the best practice for disposal of all condemned containers requires adherence to the following procedures:
a) safely defuel and purge the contents;
b) remove the valve and other fittings;
c) obliterate all markings and labels;
d) destroy the container; and
e) properly discard the container.
1.3 Container type
NGV 2 high-pressure containers are designated as follows:
Type 1. Metal.
Type 2. Resin impregnated continuous filament with metal liner with a minimum burst pressure of 125% of service pressure. This container is hoop-wrapped.
Type 3. Resin impregnated continuous filament with metal liner. This container is full-wrapped.
Type 4. Resin impregnated continuous filament with a non-metallic liner.
1.4 Terminology
In this Document, shall is used to express a requirement, i.e., a provision that the user is obliged to satisfy in order to comply with the Document; should is used to express a recommendation or that which is advised but not required; and may is used to express an option or that which is permissible within the limits of the Document.
Notes accompanying clauses do not include requirements or alternative requirements; the purpose of a note accompanying a clause is to separate from the text explanatory or informative material.
Notes to tables and figures are considered part of the table or figure and may be written as requirements.
Annexes are designated normative (mandatory) or informative (non-mandatory) to define their application.
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SPE-2.1.2-18 - Best practices for defueling, decommissioning, and disposal of liquefied natural gas vehicle fuel tanks
Preface
This is the first edition of CSA SPE-2.1.2, Best practices for defueling, decommissioning, and disposal of liquefied natural gas vehicle fuel tanks.
Scope
1.1 General
This Document contains requirements for the safe removal and disposal of liquefied natural gas (LNG) tanks from natural gas vehicles (NGV) when the tanks
a) have been condemned in accordance with visual inspection guidelines;
b) are no longer of value to an owner; or
c) have been deemed a public nuisance or imminent hazard by the local authority (abandoned, confiscated, or seized tanks.
It is the owner’s responsibility to ensure that the LNG tank on the vehicle is defueled and removed by a qualified agency whenever deemed required. Once the tank has been removed, the custodian of the tank is responsible to dispose the tank safely.
Note: Owners should obtain paperwork to document transfer of custody.
1.2 Procedure overview
In general, the best practice for disposal of a tank requires adherence to the following procedures:
a) safely defuel the contents and purge the tank
b) remove the valves and other fittings
c) obliterate all markings and labels;
d) render the tank inoperable; and
e) properly discard the tank
1.3 Terminology
In this Document, “shall” is used to express a requirement, i.e., a provision that the user is obliged to satisfy in order to comply with the Document; “should” is used to express a recommendation or that which is advised but not required; and “may” is used to express an option or that which is permissible within the limits of the Document.
Notes accompanying clauses do not include requirements or alternative requirements; the purpose of a note accompanying a clause is to separate from the text explanatory or informative material.
Notes to tables and figures are considered part of the table or figure and may be written as requirements.
Annexes are designated normative (mandatory) or informative (non-mandatory) to define their application.
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CSA/ANSI NGV 6.1-2018 - Compressed natural gas (CNG) fuel storage and delivery systems for road vehicles
Preface
This is the second edition of CSA/ANSI NGV 6.1, Compressed natural gas (CNG) fuel storage and delivery systems for road vehicles. It supersedes the previous edition published in 2016.
The first edition of CSA NGV 6.1 was a Recommended Practice that provided a recommended standard practice for vehicle fuel systems. It was written in mandatory language to accommodate its adoption by anyone wishing to do so. The second edition transitioned to a National Standard.
Scope
1.1
This Standard applies to the design, installation, inspection, repair, and maintenance of a fuel storage and delivery system installed in an on road vehicle for use with compressed natural gas (CNG). This includes a fuel system on a self-propelled vehicle for the provision of motive power.
Note: This Standard is intended to cover the fuel storage and delivery system as defined in Figure 1. Elements downstream of the regulation device(s) or stage(s) such as the low pressure delivery line and injectors are not included in the Scope of this Standard.
1.2
This Standard does not apply to:
a) stationary engines;
b) mobile equipment using natural gas as a fuel for other than propulsion;
c) electronic control module or controls strategy of a fuel management system;
d) liquefied natural gas (LNG) fuel storage systems; or
e) compressed natural gas (CNG) gaseous portion of LNG vehicles.
Future editions of this Standard may include:
a) liquefied natural gas (LNG) fuel storage system;
b) compressed natural gas (CNG) portion of an LNG vehicle;
c) storage or utilization of natural gas on boats or trains;
d) powered industrial trucks;
e) off road applications including mining applications, all-terrain vehicles; and
f) motorcycles.
1.3
Regulatory requirements may supersede the requirements of this Standard.
1.4
All references to pressure throughout this Standard are to be considered gauge pressures, unless otherwise specified.
1.5
This Standard contains SI (Metric) with corresponding English units, the purpose being to allow the Standard to be used in SI (Metric) units. American National Standard for Metric Practice, IEEE/ASTM SI 10, or ISO 80000-1, Quantities and units — Part 1: General, is used as a guide in making English conversion from metric units. If a value for a measurement and a corresponding value in other units are stated, the first stated value is to be regarded as the requirement. The given corresponding value may be approximate. If a value for a measurement and a corresponding value in other units are both specified as a quoted marking requirement, the first stated unit, or both, are to be provided.
Where the word gallon is used in this Standard, it indicates a U.S. gallon equivalent to 3.785 liters water capacity.
1.6
In this Standard, shall is used to express a requirement, i.e., a provision that the user is obliged to satisfy in order to comply with existing codes and this Standard; should is used to express a recommendation or that which is advised but not required; and may is used to express an option or that which is permissible within the limits of the Standard.
Notes accompanying clauses do not include requirements or alternative requirements; the purpose of a note accompanying a clause is to separate from the text explanatory or informative material.
Notes to tables and figures are considered part of the table or figure and may be written as requirements.
Annexes are designated normative (mandatory) or informative (non-mandatory) to define their application.
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CSA/ANSI NGV 2-2016 - Compressed natural gas vehicle fuel containers
Preface
This is the fifth edition of CSA/ANSI NGV 2, Compressed natural gas vehicle fuel containers. This Standard was prepared by the NGV 2/HGV 2 Technical Subcommittee on Standards for Compressed Natural Gas and Compressed Hydrogen Vehicle Fuel Containers, under the jurisdiction of the Automotive Technical Committee, and has been formally approved by the Technical Committee, and the American National Standards Institute.
Previous editions of this Standard, and addenda thereto, approved by the American National Standards Institute are as follows:
NGV 2-1992
NGV 2-1998
NGV 2-2000 / NGV 2a-2001
NGV 2-2007 / NGV 2a-2012 / NGV 2b-2012
Scope
1.1 General
This Standard contains requirements for the material, design, manufacture, and testing of serially produced, refillable Type NGV 2 containers intended only for the storage of compressed natural gas for vehicle operation. These containers are to be permanently attached to the vehicle. This Standard applies to containers up to and including 1 000 liters (35.4 ft3) water capacity.
1.2 Container type
Type NGV 2 containers are designated as follows:
Type 1 - Metal.
Type 2 - Resin impregnated continuous filament with metal liner with a minimum burst pressure of 125 percent of service pressure. This container is hoop-wrapped.
Type 3 - Resin impregnated continuous filament with metal liner. This container is full- wrapped.
Type 4 - Resin impregnated continuous filament with a nonmetallic liner.
1.3 Alternative construction or materials
All specifications as to construction or materials set forth herein may be satisfied by the construction or materials actually prescribed or such other construction or materials as will provide at least equivalent level of performance. Additional tests may be required to evaluate potential failure modes that pertain to the new construction or materials that are not specifically addressed in this Standard.
1.4 Units of measure
This Standard contains SI (metric) units with yard/pound quantities for reference purposes, the purpose being to allow the Standard to be used in SI (metric) units. IEEE/ASTM SI 10, or ISO 80000-1, is used as a guide in making metric conversion from inch/pound quantities. If a value for a measurement and a corresponding value in other units are stated, the first stated value is to be regarded as the requirement. The given corresponding value may be approximate. If a value for a measurement and a corresponding value in other units, are both specified as a quoted marking requirement, the first stated unit, or both are to be provided.
1.5 Terminology
In this Standard, shall is used to express a requirement, i.e., a provision that the user is obliged to satisfy in order to comply with the standard; should is used to express a recommendation or that which is advised but not required; and may is used to express an option or that which is permissible within the limits of the standard.
Notes accompanying clauses do not include requirements or alternative requirements; the purpose of a note accompanying a clause is to separate from the text explanatory or informative material.
Notes to tables and figures are considered part of the table or figure and may be written as requirements.
Annexes are designated normative (mandatory) or informative (non-mandatory) to define their application.