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Title / Demonstrate knowledge of the compaction of hot mix asphalt
Level / 3 / Credits / 5
Purpose / This unit standard is designed for people in the pavement surfacing industry who require an understanding of the practical aspects of asphalt compaction such as asphalt paving machine operators, roller operators, and asphalt construction, and may include asphalt construction supervisors.
People credited with this unit standard are able to: demonstrate knowledge of hot mix asphalt compaction equipment and operational hazards; and describe the effective compaction of hot mix asphalt.
Classification / Pavement Surfacing > Asphalt Surfacing
Available grade / Achieved
Explanatory notes
1The following requirements apply to this unit standard, and must be complied with:
New Zealand Transport Agency specifications at
NZTA P9:Specification forConstruction of Asphaltic Concrete Paving;
NZTA P9P (Auckland):Specification for Construction of Asphaltic Concrete Paving;
NZTA P11:Specification forOpen Graded Porous Asphalt;
NZTA P11 Notes:Notes to the Specification forOpen Graded Porous Asphalt.
Any requirements superseding any of the above will apply, pending the review of this unit standard.
2Assessment against this unit standard may be based on evidence from workplace and/or provider contexts.
3Definition
Job requirements take account of site conditions to meet contract specifications, and accord with procedures and work instructions written in quality manuals.
Outcomes and evidence requirements
Outcome 1
Demonstrate knowledge of hot mix asphalt compaction equipment and operational hazards.
Evidence requirements
1.1Types of equipment used for hot mix asphalt compaction are described in terms of their function.
Rangepaving machine screed, tamper bars;
rollers – static steel, vibrating, rubber-tyred, combination (vibrating drum and rubber-tyred);
hand compactor, hand-operated plate compactor.
1.2Compaction equipment is described in terms of maintenance requirements when used with hot mix asphalt.
Rangewater system, scraper, rollers, tyres, plates, oil, fuel.
1.3Hazards of compaction operations are described in terms of controls.
Rangehazards include but are not limited to – traffic, restricted vision, reversing, equipment instability, ground instability, vibration, excessive live loads.
Outcome 2
Describe the effective compaction of hot mix asphalt.
Evidence requirements
2.1Rolling operations are described in terms of sequence, pattern, and the number of rollers to maintain required laying rate while achieving compaction, in accordance with job requirements.
Rangesequence – breakdown, principal, finish;
number of passes.
2.2Techniques for achieving uniform joints and edges are described.
Rangejoints – transverse, longitudinal, hot, cold.
2.3Techniques for achieving specified shape, density, and uniformity of mat are described.
2.4Techniques for avoiding pickup, loss of macro texture, deformation, over-rolling, and cracking of the mat are described.
2.5Compaction is described in terms of achieving required strength, permeability, and life of an asphalt layer.
2.6Compaction is described in terms of factors that influence the result.
Rangefactors include but are not limited to – road temperature, ambient temperature, wind, mat thickness, mat temperature, mix type, roller type.
Planned review date / 31 December 2016Status information and last date for assessment for superseded versions
Process / Version / Date / Last Date for AssessmentRegistration / 1 / 24 March 1998 / 31 December 2013
Revision / 2 / 5 January 1999 / 31 December 2013
Review / 3 / 27 October 2005 / 31 December 2013
Review / 4 / 15 March 2012 / N/A
Consent and Moderation Requirements (CMR) reference / 0101
This CMR can be accessed at
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.
Comments on this unit standard
Please contact Infrastructure if you wish to suggest changes to the content of this unit standard.
Infrastructure ITOSSB Code 101813 / New Zealand Qualifications Authority 2018