Conformance testing: Difference between revisions

From Wikipedia, the free encyclopedia
Jump to navigation Jump to search
imported>Jens Meiert
m Added missing comma (Oxford comma consistent with previous sections of article)
 
imported>Sargdub
tidy
 
Line 1: Line 1:
{{Short description|Type of testing for standards, contracts and regulations}}
{{Short description|Type of testing for standards, contracts and regulations}}
'''Conformance testing''' — an element of '''conformity assessment''', and also known as '''compliance testing''', or '''type testing''' is [[Test method|testing]] or other activities that determine whether a process, product, or service complies with the requirements of a [[specification]], [[technical standard]], [[contract]], or [[regulation]].<ref name="TrenkaevInter03">{{cite book |chapter-url=https://books.google.com/books?id=9ta5rLb1CkkC&pg=PA226 |chapter=Interoperability Testing Based on a Fault Model for a System of Communicating FSMs |title=Testing of Communicating Systems: 15th IFIP International Conference, TestCom 2003 |author1=Trenkaev, V. |author2=Kim, M. |author3=Seol, S.  |editor1=Hogrefe, D. |editor2=Wiles, A.  |publisher=Springer Science & Business Media |year=2003 |pages=226–242 |isbn=9783540401230}}</ref><ref name="WareTheNeed90">{{cite book |chapter-url=https://books.google.com/books?id=2FQf_pCCUeUC&pg=PA14 |chapter=Chapter 2: The Need for Mutual Recognition of Test Laboratories |title=Test Quality for Construction, Materials and Structures: Proceedings of the International RILEM/ILAC Symposium |author=Ware, J.E. |editor=Fickelson, M. |publisher=CRC Press |year=1990 |pages=12–18 |isbn=9780412394508}}</ref><ref name="WerstiukRelay07">{{cite book |chapter-url=https://books.google.com/books?id=HCMDxjJnnF8C&pg=PA13 |chapter=Chapter 2: Relay Testing Fundamentals |title=The Relay Testing Handbook: Relay Testing Fundamentals |author=Werstiuk, C. |publisher=Valence Electrical Training Services |year=2007 |pages=13–52 |isbn=9781934348017}}</ref><ref name="INCITSReport05">{{cite web |url=http://www.incits.org/tc_home/m1htm/docs/m1050067.pdf |archive-url=https://web.archive.org/web/20061213213606/http://www.incits.org/tc_home/m1htm/docs/m1050067.pdf |title=Report on Issues for Harmonizing Conformity Assessment to Biometric Standards |author=M1 Ad-Hoc Group on Issues for Harmonizing Conformity Assessment to Biometric Standards |publisher=InterNational Committee for Information Technology Standards |date=16 March 2005 |archive-date=13 December 2006 |access-date=22 February 2018}}</ref><ref name="ISOWhatIs">{{cite web |url=https://www.iso.org/conformity-assessment.html |title=What is conformity assessment? |publisher=International Organization for Standardization |access-date=22 February 2018}}</ref> Testing is often either [[event condition action|logical test]]ing or [[physical test]]ing. The test procedures may involve other criteria from [[test functions for optimization|mathematical testing]] or [[chemical test]]ing. Beyond simple conformance, other requirements for efficiency, interoperability, or compliance may apply. Conformance testing may be undertaken by the producer of the product or service being assessed, by a user, or by an [[accredited]] independent organization, which can sometimes be the author of the standard being used. When testing is accompanied by [[certification]], the products or services may then be [[Advertising|advertised]] as being certified in compliance with the referred [[technical standard]]. Manufacturers and suppliers of products and services rely on such certification including listing on the certification body's website, to assure quality to the end user and that competing suppliers are on the same level.
'''Conformance testing''' and also known as '''compliance testing''' or '''type testing''', is [[Test method|testing]] or other activities that determine whether a process, product, or service complies with the requirements of a [[specification]], [[technical standard]], [[contract]], or [[regulation]].<ref name="TrenkaevInter03">{{cite book |chapter-url=https://books.google.com/books?id=9ta5rLb1CkkC&pg=PA226 |chapter=Interoperability Testing Based on a Fault Model for a System of Communicating FSMs |title=Testing of Communicating Systems: 15th IFIP International Conference, TestCom 2003 |author1=Trenkaev, V. |author2=Kim, M. |author3=Seol, S.  |editor1=Hogrefe, D. |editor2=Wiles, A.  |publisher=Springer Science & Business Media |year=2003 |pages=226–242 |isbn=9783540401230}}</ref><ref name="WareTheNeed90">{{cite book |chapter-url=https://books.google.com/books?id=2FQf_pCCUeUC&pg=PA14 |chapter=Chapter 2: The Need for Mutual Recognition of Test Laboratories |title=Test Quality for Construction, Materials and Structures: Proceedings of the International RILEM/ILAC Symposium |author=Ware, J.E. |editor=Fickelson, M. |publisher=CRC Press |year=1990 |pages=12–18 |isbn=9780412394508}}</ref><ref name="WerstiukRelay07">{{cite book |chapter-url=https://books.google.com/books?id=HCMDxjJnnF8C&pg=PA13 |chapter=Chapter 2: Relay Testing Fundamentals |title=The Relay Testing Handbook: Relay Testing Fundamentals |author=Werstiuk, C. |publisher=Valence Electrical Training Services |year=2007 |pages=13–52 |isbn=9781934348017}}</ref><ref name="INCITSReport05">{{cite web |url=http://www.incits.org/tc_home/m1htm/docs/m1050067.pdf |archive-url=https://web.archive.org/web/20061213213606/http://www.incits.org/tc_home/m1htm/docs/m1050067.pdf |title=Report on Issues for Harmonizing Conformity Assessment to Biometric Standards |author=Ad-Hoc Group on Issues for Harmonizing Conformity Assessment to Biometric Standards |publisher=InterNational Committee for Information Technology Standards |date=16 March 2005 |archive-date=13 December 2006 |access-date=22 February 2018}}</ref><ref name="ISOWhatIs">{{cite web |url=https://www.iso.org/conformity-assessment.html |title=What is conformity assessment? |publisher=International Organization for Standardization |access-date=22 February 2018}}</ref> It is an element of the more general '''conformity assessment'''.


Aside from the various types of testing, related conformance testing activities include:
Testing is often either [[event condition action|logical test]]ing or [[physical test]]ing. The test procedures may involve other criteria from [[test functions for optimization|mathematical testing]] or [[chemical test]]ing. Beyond simple conformance, other requirements for efficiency, interoperability, or compliance may apply.
* [[Surveillance]]
 
* [[Inspection]]
Conformance testing may be undertaken by the producer of the product or service being assessed, by a user, or by an [[accredited]] independent organization, which can sometimes be the author of the standard being used. When testing is accompanied by [[certification]], the products or services may then be [[Advertising|advertised]] as being certified in compliance with the referred [[technical standard]]. Manufacturers and suppliers of products and services rely on such certification including listing on the certification body's website, to assure quality to the end user and that competing suppliers are on the same level.
* [[Auditing]]
 
* [[Certification]]
Aside from the various types of testing, related conformance testing activities may also include [[surveillance]], [[inspection]], [[auditing]], [[certification]], and [[accreditation]].
* [[Accreditation]].


==Forms of conformance testing==
==Forms of conformance testing==
Line 30: Line 29:


=== Software engineering ===
=== Software engineering ===
In [[software testing]], conformance testing verifies that a product performs according to its specified standards. [[Compiler]]s, for instance, are extensively tested to determine whether they meet the recognized standard for that language.<ref name="GoerigkTowards99">{{cite book |chapter-url=https://books.google.com/books?id=gM6AS9_XwtgC&pg=PA62 |chapter=Towards Rigorous Compiler Implementation Verification |title=Collaboration Between Human and Artificial Societies: Coordination and Agent-Based Distributed Computing |author1=Goerigk, W. |author2=Simon, F. |editor=Padget, J.A. |publisher=Springer Science & Business Media |pages=62–73 |year=1999 |isbn=9783540669302}}</ref><ref name="CuginiACent01">{{cite book |chapter-url=https://books.google.com/books?id=hrizEY2BWOoC&pg=PA258 |chapter=FORTRAN Test Programs |title=A Century of Excellence in Measurements, Standards, and Technology |author=Cugini, J. |editor=Lide, D.R. |publisher=CRC Press |pages=258–259 |year=2001 |isbn=9780849312472}}</ref>
In [[software testing]], conformance testing verifies that a product performs according to its specified standards. [[Compiler]]s, for instance, are extensively tested to determine whether they meet the recognized standard for that language.<ref name="GoerigkTowards99">{{cite book |chapter-url=https://books.google.com/books?id=gM6AS9_XwtgC&pg=PA62 |chapter=Towards Rigorous Compiler Implementation Verification |title=Collaboration Between Human and Artificial Societies: Coordination and Agent-Based Distributed Computing |author1=Goerigk, W. |author2=Simon, F. |editor=Padget, J.A. |publisher=Springer Science & Business Media |pages=62–73 |year=1999 |isbn=9783540669302}}</ref><ref name="CuginiACent01">{{cite book |chapter-url=https://books.google.com/books?id=hrizEY2BWOoC&pg=PA258 |chapter=FORTRAN Test Programs |title=A Century of Excellence in Measurements, Standards, and Technology |author=Cugini, J. |editor=Lide, D.R. |publisher=CRC Press |pages=258–259 |year=2001 |isbn=9780849312472}}</ref>


=== Electronic and electrical engineering ===
=== Electronic and electrical engineering ===
In [[electronic engineering]] and [[electrical engineering]], some countries and business environments (such as telecommunication companies) require that an electronic product meet certain requirements before they can be sold.<ref name="WerstiukRelay07" /><ref name="RyanHigh01">{{cite book |title=High Voltage Engineering and Testing |editor=Ryan, H.M. |publisher=The Institution of Electrical Engineers |edition=2nd |year=2001 |pages=726 |isbn=9780852967751}}</ref> Standards for telecommunication products written by standards organizations such as [[American National Standards Institute|ANSI]], the [[Federal Communications Commission|FCC]], and [[International Electrotechnical Commission|IEC]] have certain criteria that a product must meet before compliance is recognized. In countries such as Japan, China, Korea, and some parts of Europe, products cannot be sold unless they are known to meet those requirements specified in the standards.<ref name="COCIRHowDoes">{{cite web |url=https://www.bomcheck.net/rohs/how-does-bomcheck-manage-compliance-with-rohs-restrictions-in-china-korea-japan |title=How does BOMcheck manage compliance with RoHS restrictions in China, Korea and Japan? |work=BOMcheck.net |publisher=COCIR |access-date=22 February 2018}}</ref><ref name="EURLex31993">{{cite web |url=http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=CELEX:31993L0068:en:HTML |title=EUR-Lex - 31993L0068 - EN |work=EUR-Lex |publisher=European Union |date=30 August 1993 |access-date=22 February 2018}}</ref> Usually, manufacturers set their own requirements to ensure product quality, sometimes with levels much higher than what the governing bodies require. Compliance is realized after a product passes a series of tests without occurring some specified mode of failure.
In [[electronic engineering]] and [[electrical engineering]], some countries and business environments (such as telecommunication companies) require that an electronic product meet certain requirements before they can be sold.<ref name="WerstiukRelay07" /><ref name="RyanHigh01">{{cite book |title=High Voltage Engineering and Testing |editor=Ryan, H.M. |publisher=The Institution of Electrical Engineers |edition=2nd |year=2001 |pages=726 |isbn=9780852967751}}</ref> Standards for telecommunication products written by standards organizations such as [[American National Standards Institute|ANSI]], the [[Federal Communications Commission|FCC]], and [[International Electrotechnical Commission|IEC]] have certain criteria that a product must meet before compliance is recognized. In countries such as Japan, China, Korea, and some parts of Europe, products cannot be sold unless they are known to meet those requirements specified in the standards.<ref name="COCIRHowDoes">{{cite web |url=https://www.bomcheck.net/rohs/how-does-bomcheck-manage-compliance-with-rohs-restrictions-in-china-korea-japan |title=How does BOMcheck manage compliance with RoHS restrictions in China, Korea and Japan? |work=BOMcheck.net |publisher=COCIR |access-date=22 February 2018}}</ref><ref name="EURLex31993">{{cite web |url=http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=CELEX:31993L0068:en:HTML |title=EUR-Lex - 31993L0068 - EN |work=EUR-Lex |publisher=European Union |date=30 August 1993 |access-date=22 February 2018}}</ref> Usually, manufacturers set their own requirements to ensure product quality, sometimes with levels much higher than what the governing bodies require. Compliance is realized after a product passes a series of tests without occurring some specified mode of failure.


Line 50: Line 47:
; Powerline surge immunity : A surge is applied to the line voltage.
; Powerline surge immunity : A surge is applied to the line voltage.


== Standardization and agreements ==
== Standards ==
 
Several international standards relating to conformance testing are published by the [[International Organization for Standardization]] (ISO) and covered in the divisions of ICS 03.120.20 for management<ref name=pccc>{{cite web |last = International Organization for Standardization |author-link = International Organization for Standardization |title = 03.120.20: Product and company certification. Conformity assessment |url = http://www.iso.org/iso/products/standards/catalogue_ics_browse.htm?ICS1=03&ICS2=120&ICS3=20& |access-date=2009-04-10}}</ref> and ICS 23.040.01 for technical.<ref name=pcpg>{{cite web |last = International Organization for Standardization |author-link = International Organization for Standardization |title = 23.040.01: Pipeline components and pipelines in general |url = http://www.iso.org/iso/products/standards/catalogue_ics_browse.htm?ICS1=23&ICS2=040&ICS3=01& |access-date=2009-04-10}}</ref> Other standalone ISO standards include:
Several international standards relating to conformance testing are published by the [[International Organization for Standardization]] (ISO) and covered in the divisions of ICS 03.120.20 for management<ref name=pccc>{{cite web |last = International Organization for Standardization |author-link = International Organization for Standardization |title = 03.120.20: Product and company certification. Conformity assessment |url = http://www.iso.org/iso/products/standards/catalogue_ics_browse.htm?ICS1=03&ICS2=120&ICS3=20& |access-date=2009-04-10}}</ref> and ICS 23.040.01 for technical.<ref name=pcpg>{{cite web |last = International Organization for Standardization |author-link = International Organization for Standardization |title = 23.040.01: Pipeline components and pipelines in general |url = http://www.iso.org/iso/products/standards/catalogue_ics_browse.htm?ICS1=23&ICS2=040&ICS3=01& |access-date=2009-04-10}}</ref> Other standalone ISO standards include:


Line 58: Line 54:
* ''ISO/IEC 18009:1999 Information technology—Programming languages—Ada: Conformity assessment of a language processor'' <ref name=itpl>{{cite web |last = International Organization for Standardization |author-link = International Organization for Standardization |title = ISO/IEC 18009:1999 Information technology -- Programming languages -- Ada: Conformity assessment of a language processor |url = http://www.iso.org/iso/iso_catalogue/catalogue_tc/catalogue_detail.htm?csnumber=31051 |access-date=2009-04-10}}</ref>
* ''ISO/IEC 18009:1999 Information technology—Programming languages—Ada: Conformity assessment of a language processor'' <ref name=itpl>{{cite web |last = International Organization for Standardization |author-link = International Organization for Standardization |title = ISO/IEC 18009:1999 Information technology -- Programming languages -- Ada: Conformity assessment of a language processor |url = http://www.iso.org/iso/iso_catalogue/catalogue_tc/catalogue_detail.htm?csnumber=31051 |access-date=2009-04-10}}</ref>


===Conformity assessment and mutual recognition agreements===
===Mutual recognition agreements===
Many countries sign [[mutual recognition agreement]]s (MRAs) with other countries in order to promote trade of and facilitate market access to goods and services, while making it easier to meet a country's conformance testing requirements.<ref name="EC-MRA18">{{cite web |url=https://ec.europa.eu/growth/single-market/goods/international-aspects/mutual-recognition-agreements_en |title=Mutual Recognition Agreements |publisher=European Commission |date=22 February 2018 |access-date=22 February 2018}}</ref><ref name="NISTMutual17">{{cite web |url=https://www.nist.gov/standardsgov/what-we-do/conformity-assessment/mutual-recognition-agreements-mras |title=Mutual Recognition Agreements for Conformity Assessment of Telecommunications Equipment |publisher=National Institute of Standards and Technology |date=6 September 2017 |access-date=22 February 2018}}</ref><ref name="ISO68:2002">{{cite web |url=https://www.iso.org/standard/29363.html |title=ISO/IEC Guide 68:2002 Arrangements for the recognition and acceptance of conformity assessment results |publisher=International Organization for Standards |date=January 2002 |access-date=22 February 2018}}</ref> Additionally, these agreements have the advantage of increasing confidence in conformance assessment bodies (e.g., testing labs and certification bodies),<ref name="NISTMutual17" /> and by extension, product quality.<ref name="ISOWhatIs"/><ref name="WTOTech">{{cite web| url=https://www.wto.org/english/tratop_e/tbt_e/tbt_info_e.htm |title=Technical Information on Technical barriers to trade |work=Trade Topics |publisher=World Trade Organization |access-date=22 February 2018}}</ref> An example is the [[IAF MLA]] which is an agreement for the mutual recognition of accredited certification between IAF Accreditation Body (AB) Member signatories.
Many countries sign [[mutual recognition agreement]]s (MRAs) with other countries in order to promote trade of and facilitate market access to goods and services, while making it easier to meet a country's conformance testing requirements.<ref name="EC-MRA18">{{cite web |url=https://ec.europa.eu/growth/single-market/goods/international-aspects/mutual-recognition-agreements_en |title=Mutual Recognition Agreements |publisher=European Commission |date=22 February 2018 |access-date=22 February 2018}}</ref><ref name="NISTMutual17">{{cite web |url=https://www.nist.gov/standardsgov/what-we-do/conformity-assessment/mutual-recognition-agreements-mras |title=Mutual Recognition Agreements for Conformity Assessment of Telecommunications Equipment |publisher=National Institute of Standards and Technology |date=6 September 2017 |access-date=22 February 2018}}</ref><ref name="ISO68:2002">{{cite web |url=https://www.iso.org/standard/29363.html |title=ISO/IEC Guide 68:2002 Arrangements for the recognition and acceptance of conformity assessment results |publisher=International Organization for Standards |date=January 2002 |access-date=22 February 2018}}</ref> Additionally, these agreements have the advantage of increasing confidence in conformance assessment bodies (e.g., testing labs and certification bodies),<ref name="NISTMutual17" /> and by extension, product quality.<ref name="ISOWhatIs"/><ref name="WTOTech">{{cite web| url=https://www.wto.org/english/tratop_e/tbt_e/tbt_info_e.htm |title=Technical Information on Technical barriers to trade |work=Trade Topics |publisher=World Trade Organization |access-date=22 February 2018}}</ref> An example is the [[IAF MLA]] which is an agreement for the mutual recognition of accredited certification between IAF Accreditation Body (AB) Member signatories.



Latest revision as of 02:25, 3 June 2025

Template:Short description Conformance testing and also known as compliance testing or type testing, is testing or other activities that determine whether a process, product, or service complies with the requirements of a specification, technical standard, contract, or regulation.[1][2][3][4][5] It is an element of the more general conformity assessment.

Testing is often either logical testing or physical testing. The test procedures may involve other criteria from mathematical testing or chemical testing. Beyond simple conformance, other requirements for efficiency, interoperability, or compliance may apply.

Conformance testing may be undertaken by the producer of the product or service being assessed, by a user, or by an accredited independent organization, which can sometimes be the author of the standard being used. When testing is accompanied by certification, the products or services may then be advertised as being certified in compliance with the referred technical standard. Manufacturers and suppliers of products and services rely on such certification including listing on the certification body's website, to assure quality to the end user and that competing suppliers are on the same level.

Aside from the various types of testing, related conformance testing activities may also include surveillance, inspection, auditing, certification, and accreditation.

Forms of conformance testing

The UK government identifies three forms of testing or assessment:[6]

  • 1st party assessment (self assessment)
  • 2nd party assessment (assessment by a purchaser or user of a product or service)
  • 3rd party assessment (undertaken by an independent organisation)

Typical areas of application

Conformance testing is applied in various industries where a product or service must meet specific quality and/or regulatory standards. This includes areas such as:[1][3][4][7][8]

  • biocompatibility proofing
  • data and communications protocol engineering
  • document engineering
  • electronic and electrical engineering
  • medical procedure proofing
  • pharmaceutical packaging
  • software engineering
  • building construction (fire)

In all such testing, the subject of test is not just the formal conformance in aspects of completeness of filed proofs, validity of referred certificates, and qualification of operating staff. Rather, it also heavily focuses on operational conditions, physical conditions, and applied test environments. By extension conformance testing leads to a vast set of documents and files that allow for reiterating all performed tests.

Software engineering

In software testing, conformance testing verifies that a product performs according to its specified standards. Compilers, for instance, are extensively tested to determine whether they meet the recognized standard for that language.[9][10]

Electronic and electrical engineering

In electronic engineering and electrical engineering, some countries and business environments (such as telecommunication companies) require that an electronic product meet certain requirements before they can be sold.[3][11] Standards for telecommunication products written by standards organizations such as ANSI, the FCC, and IEC have certain criteria that a product must meet before compliance is recognized. In countries such as Japan, China, Korea, and some parts of Europe, products cannot be sold unless they are known to meet those requirements specified in the standards.[12][13] Usually, manufacturers set their own requirements to ensure product quality, sometimes with levels much higher than what the governing bodies require. Compliance is realized after a product passes a series of tests without occurring some specified mode of failure.

Compliance testing for electronic devices include emissions tests, immunity tests, and safety tests.[14] Emissions tests ensure that a product will not emit harmful electromagnetic interference in communication and power lines. Immunity tests ensure that a product is immune to common electrical signals and electromagnetic interference (EMI) that will be found in its operating environment, such as electromagnetic radiation from a local radio station or interference from nearby products. Safety tests ensure that a product will not create a safety risk from situations such as a failed or shorted power supply, blocked cooling vent, and powerline voltage spikes and dips.

For example, Ericsson's telecommunications research and development subsidiary Telcordia Technologies publishes conformance standards for telecommunication equipment to pass the following tests:[15]

Radiated immunity
An antenna is used to subject the device to electromagnetic waves, covering a large frequency range (usually from 80 MHz to 6 GHz).
Radiated emissions
One or more antennas are used to measure the amplitude of the electromagnetic waves that a device emits. The amplitude must be under a set limit, with the limit depending on the device's classification.
Conducted immunity
Low frequency signals (usually 10 kHz to 80 MHz) are injected onto the data and power lines of a device. This test is used to simulate the coupling of low frequency signals onto the power and data lines, such as from a local AM radio station.
Conducted emissions
Similar to radiated emissions, except the signals are measured at the power lines with a filter device.
Electrostatic discharge (ESD) immunity
Electrostatic discharges with various properties (rise time, peak voltage, fall time, and half time) are applied to the areas on the device that are likely to be discharged too, such as the faces, near user accessible buttons, etc. Discharges are also applied to a vertical and horizontal ground plane to simulate an ESD event on a nearby surface. Voltages are usually from 2 kV to 15 kV, but commonly go as high as 25 kV or more.
Electrical Fast Transient Burst immunity (EFTB)
Bursts of high voltage pulses are applied to the powerlines to simulate events such as repeating voltage spikes from a motor.
Powerline dip immunity
The line voltage is slowly dropped down then brought back up.
Powerline surge immunity
A surge is applied to the line voltage.

Standards

Several international standards relating to conformance testing are published by the International Organization for Standardization (ISO) and covered in the divisions of ICS 03.120.20 for management[16] and ICS 23.040.01 for technical.[17] Other standalone ISO standards include:

  • ISO/TR 13881:2000 Petroleum and natural gas industries—Classification and conformity assessment of products, processes and services[18]
  • ISO 18436-4:2008 Condition monitoring and diagnostics of machines—Requirements for qualification and assessment of personnel—Part 4: Field lubricant analysis[19]
  • ISO/IEC 18009:1999 Information technology—Programming languages—Ada: Conformity assessment of a language processor [20]

Mutual recognition agreements

Many countries sign mutual recognition agreements (MRAs) with other countries in order to promote trade of and facilitate market access to goods and services, while making it easier to meet a country's conformance testing requirements.[21][22][23] Additionally, these agreements have the advantage of increasing confidence in conformance assessment bodies (e.g., testing labs and certification bodies),[22] and by extension, product quality.[5][24] An example is the IAF MLA which is an agreement for the mutual recognition of accredited certification between IAF Accreditation Body (AB) Member signatories.

See also

References

Template:Reflist

Template:Product testing Template:Software testing

  1. a b Script error: No such module "citation/CS1".
  2. Script error: No such module "citation/CS1".
  3. a b c Script error: No such module "citation/CS1".
  4. a b Script error: No such module "citation/CS1".
  5. a b Script error: No such module "citation/CS1".
  6. Department for Business, Energy and Industrial Strategy, Conformity Assessment and Accreditation Policy in the UK, published February 2017, accessed 8 August 2020
  7. Script error: No such module "citation/CS1".
  8. Script error: No such module "citation/CS1".
  9. Script error: No such module "citation/CS1".
  10. Script error: No such module "citation/CS1".
  11. Script error: No such module "citation/CS1".
  12. Script error: No such module "citation/CS1".
  13. Script error: No such module "citation/CS1".
  14. Script error: No such module "citation/CS1".
  15. Script error: No such module "citation/CS1".
  16. Script error: No such module "citation/CS1".
  17. Script error: No such module "citation/CS1".
  18. Script error: No such module "citation/CS1".
  19. Script error: No such module "citation/CS1".
  20. Script error: No such module "citation/CS1".
  21. Script error: No such module "citation/CS1".
  22. a b Script error: No such module "citation/CS1".
  23. Script error: No such module "citation/CS1".
  24. Script error: No such module "citation/CS1".