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Title / Pig a pipeline in a gas network
Level / 4 / Credits / 4
Purpose / People credited with this unit standard are able to: locate and identify procedures, documentation, and equipment for pigging a gas pipeline; load and launch a pig; receive and unload a pig from a gas pipeline; and complete reporting and documentation.
Classification / Gas Industry > GasNetwork Construction
Available grade / Achieved
Explanatory notes
1This unit standard is intended for, but is not limited to, workplace assessment. The range statements relate to enterprise specific equipment, procedures, and processes.
2The current version of the following documents must be complied with:
Health and Safety in Employment Act 1992;
NZS 5258:2003 Gas distribution networks available at
3All work practices must comply with regulations and codes of practice pertaining to the gas industry.
4Definitions
Company proceduresmeans the documented methods for performing work activities and include health and safety, environmental, and quality management requirements. They may refer to manuals, codes of practice, or policy statements.
Pigs are devices for insertion into pipelines for the purpose of cleaning the lines or separating products.
Outcomes and evidence requirements
Outcome 1
Locate and identify procedures, documentation, and equipment for pigging a gas pipeline.
Evidence requirements
1.1Company procedures for pigging a gas pipeline are located and interpreted in relation to specified job requirements.
1.2Job instructions and system specifications are confirmed in accordance with company procedures.
Rangeinstructions include but are not limited to – site location, consents.
1.3Reasons for pig usage are described according to site specific application.
Rangemay include but is not limited to – cleaning, purging, clearing blockages.
1.4Pig types are identified according to application and site pigging requirements.
Rangefoam, displacement, gauging, batching.
1.5Equipment is described in terms of hazards of incorrect application and operation, and the steps to avoid them are described in accordance with company procedures.
Rangehazards may include but are not limited to – stuck pig, reduced flow rates, process interruption.
1.6Resource requirements are identified and sourced in accordance with company procedures.
Rangeplant, tools, materials, documentation, personnel, communication equipment.
Outcome 2
Load and launch a pig.
Evidence requirements
2.1Safety and environmental hazards are identified, then isolated, removed, or minimised, in accordance with company procedures.
Rangemay include – signage, barriers, personal protective equipment, safe access and egress, gas escape, fire, explosion, asphyxiation, other utilities, temporary traffic control, environmental protection, excavations.
2.2The pig is loaded in accordance with manufacturer’s instructions and company procedures.
2.3Pig launching system checks are made in accordance with company procedures.
Rangepressure, isolations, in line valves are confirmed open.
2.4The pig is launched in accordance with manufacturer’s instructions and company procedures.
2.5Communication with relevant personnel is maintained during pig launching operation in accordance with company procedures.
Outcome 3
Receive and unload a pig from a gas pipeline.
Evidence requirements
3.1Pig receiving system checks are made in accordance with company procedures.
Rangemay include but is not limited to – pressure, isolations, safety equipment, pig receiver.
3.2The pig is received in accordance with manufacturer’s instructions and company procedures.
3.3Pig unloading system checks are carried out in accordance with company procedures.
Rangemay include but is not limited to – pressure, isolations, catchment, equipment, safety equipment.
3.4The pig is unloaded in accordance with manufacturer’s and site procedures.
3.5Residual materials are disposed of in accordance with consents and company procedures.
Rangemay include but is not limited to – water, shavings, debris.
3.6Findings are noted and recorded in accordance with company procedures.
Rangecondition of pig, analysis of debris, follow-up actions.
Outcome 4
Complete reporting and documentation.
Evidence requirements
4.1Information is communicated to other parties, both internal and external, in accordance with company procedures.
Rangemay include but is not limited to – special conditions, completion notice, additional work.
4.2Records and documents are completed and processed in accordance with company procedures.
Replacement information / This unit standard and unit standard 9551were replaced by unit standard 30376.This unit standard is expiring. Assessment against the unit standard must take place by the last date for assessments set out below.
Status information and last date for assessment for superseded versions
Process / Version / Date / Last Date for AssessmentRegistration / 1 / 20 November 2006 / 31 December 2020
Review / 2 / 21 May 2010 / 31 December 2020
Review / 3 / 17 August 2017 / 31 December 2020
Consent and Moderation Requirements (CMR) reference / 0014
This CMR can be accessed at http://www.nzqa.govt.nz/framework/search/index.do.
Please note
Providers must be granted consent to assess against standards (accredited) by NZQA, before they can report credits from assessment against unit standards or deliver courses of study leading to that assessment.
Industry Training Organisations must be granted consent to assess against standards by NZQA before they can register credits from assessment against unit standards.
Providers and Industry Training Organisations, which have been granted consent and which are assessing against unit standards must engage with the moderation system that applies to those standards.
Requirements for consent to assess and an outline of the moderation system that applies to this standard are outlined in the Consent and Moderation Requirements (CMR). The CMR 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.
MITO New Zealand IncorporatedSSB Code 101542 / New Zealand Qualifications Authority 2019