9578 version 4
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Carry out a Direct Current Voltage Gradient (DCVG) survey in the gas
transmission industry
Level
4
Credits
3
Purpose This unit standard is for people working, or intending to work, in the gas
transmission industry.
People credited with this unit standard are, in the gas transmission industry,
able to: demonstrate knowledge of DCVG survey equipment used in the gas
transmission industry; use DCVG survey equipment; locate and use
documentation and reporting procedures for a DCVG survey; and report the
results of DCVG survey.
Subfield
Gas Industry
Domain
Gas Transmission Operations
Status
Registered
Status date
22 May 2009
Date version published
22 May 2009
Planned review date
31 December 2014
Entry information
Open.
Accreditation
Evaluation of documentation and visit by NZQA and
industry.
Standard setting body (SSB)
NZ Motor Industry Training Organisation (Incorporated)
(MITO)
Accreditation and Moderation Action Plan (AMAP) reference
0114
This AMAP can be accessed at http://www.nzqa.govt.nz/framework/search/index.do.
Special notes
1
Performance of the elements of this unit standard must comply with relevant site
requirements, and the following legislation and standards:
Health and Safety in Employment Act 1992;
Resource Management Act 1991;
AS 2832.2-2003, Cathodic protection of metals – Compact buried structures;
BS 7361-1:1991, Cathodic protection – Code of practice for land and marine
applications;
 New Zealand Qualifications Authority 2016
9578 version 4
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NACE TM 0169-2000 Laboratory Corrosion Testing of Metals, a National Association
of Corrosion Engineers Standard (North America).
2
Definition
Company procedures refer to the documented methods for performing work activities
and include health and safety, environmental, quality management, and site
requirements. They may refer to manuals, codes of practice, or policy statements.
Elements and performance criteria
Element 1
Demonstrate knowledge of DCVG survey equipment used in the gas transmission
industry.
Performance criteria
1.1
DCVG survey equipment is located, and its use is explained in terms of its
application to a specific site.
Range
1.2
cathodic protection systems interruption device, direct current
voltage gradient meter, pipe locator.
DCVG survey equipment functions are explained to identify the type of
information relayed in terms of the application of site specific equipment.
Range
coating breaks, isolation faults.
Element 2
Use DCVG survey equipment in the gas transmission industry.
Performance criteria
2.1
Safety procedures relating to DCVG techniques are used in accordance with
company procedures.
2.2
Pipeline conditions are assessed to determine the need to use DCVG survey
equipment.
Range
low test point readings, failed flange isolation kits, failed coating
systems.
2.3
DCVG survey equipment is operated in accordance with company procedures
and manufacturer's instructions.
2.4
Potential hazards of incorrect application and operation are explained in
accordance with company procedures and manufacturer's instructions.
 New Zealand Qualifications Authority 2016
9578 version 4
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Element 3
Locate and use documentation and reporting criteria for a DCVG survey in the gas
transmission industry.
Performance criteria
3.1
Specified documentation related to the operation of DCVG equipment are
located, and are used in accordance with company procedures and
manufacturer's instructions.
Range
3.2
General site equipment documentation is located and used in accordance with
company procedures.
Range
3.3
test certificates, certification, standards for safety, standards for in
service safety inspection and testing of equipment, identification
tags, labels.
manufacturer's information, equipment operating manuals, safety
procedures, operating procedures, maintenance procedures.
International cathodic protection standards and reporting criteria are used in
accordance with company procedures.
Range
British standards, Australian standards, North American corrosion
engineer standards.
Element 4
Report the results of DCVG survey in the gas transmission industry.
Performance criteria
4.1
Corrections to primary data of DCVG survey are made in accordance with
company procedures.
4.2
Results of DCVG survey are calculated from primary data in accordance with
company procedures.
4.3
Deviations from the expected range of results are investigated and actions are
taken in accordance with company procedures.
4.4
The report includes all information gathered in the DCVG survey in accordance
with company procedures.
4.5
Outcomes of the analysis are reported and conclusions are drawn in
accordance with company procedures international standards.
Range
British standards, Australian standards, North American corrosion
engineer standards.
 New Zealand Qualifications Authority 2016
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Please note
Providers must be accredited by NZQA, or an inter-institutional body with delegated
authority for quality assurance, before they can report credits from assessment against
unit standards or deliver courses of study leading to that assessment.
Industry Training Organisations must be accredited by NZQA before they can register
credits from assessment against unit standards.
Accredited providers and Industry Training Organisations assessing against unit standards
must engage with the moderation system that applies to those standards.
Accreditation requirements and an outline of the moderation system that applies to this
standard are outlined in the Accreditation and Moderation Action Plan (AMAP). The
AMAP also includes useful information about special requirements for organisations
wishing to develop education and training programmes, such as minimum qualifications for
tutors and assessors, and special resource requirements.
Comments on this unit standard
Please contact the NZ Motor Industry Training Organisation (Incorporated) (MITO)
info@mito.org.nz if you wish to suggest changes to the content of this unit standard.
 New Zealand Qualifications Authority 2016