NZQA registered unit standard
Title
Classify hazardous areas
Level
6
Purpose
17069 version 2
Page 1 of 8
Credits
4
This unit standard requires the ability to gather and analyse
data relative to explosion hazards, determine the extent of risk,
and establish and document zones.
This unit standard is for engineers or engineering associates
who are responsible for classifying areas where
flammable/combustible materials may exist.
People credited with this unit standard are able to:
 demonstrate knowledge of explosive atmospheres and
explosion-protection principles;
 demonstrate knowledge of processes involved in gathering
and analysing technical data to classify non-specific
hazardous areas;
 determine the type and extent of explosion hazard;
 establish the type and extent of classes/zones; and
 document classification and delineation of zones.
Classification
Explosive Atmospheres > Electrical Apparatus in Explosive
Atmospheres - Compliance
Available grade
Achieved
Explanatory notes
1
This unit standard has been designed for training and assessment on-job or off-job in
a simulated environment which includes explosion-protected apparatus and wiring
systems similar to those encountered in a real workplace.
2
Candidates who achieve this unit standard will be given industry endorsement for
explosion-protection techniques relating to one or more of: mining, gases or dusts,
depending on which explosion-protection technique competence is demonstrated.
The explosion-protection endorsements are as follows:
Unit endorsement suffix
Competence demonstrated
‘Gases’
Gas hazards only
‘Dusts’
Dust hazards only
For further detail about the explosion-protection endorsements, please contact
ETITO at http://www.etito.co.nz.
ElectroTechnology Industry Training Organisation
SSB Code 100401
 New Zealand Qualifications Authority 2016
NZQA registered unit standard
17069 version 2
Page 2 of 8
3
This unit standard is directly equivalent to Unit 2.16 Classify hazardous areas in the
Australian/New Zealand Standard AS/NZS 4761.1:2008 Competencies for working
with electrical equipment in hazardous areas (EEHA) Part 1: Competency standards
and includes essential skills and knowledge as specified in the relevant clauses. It
aligns with Australian Competency Standards UEENEEM052A and UEENEEM053A
from UEE07 Electrotechnology Training Package Version 3.1 (copyright Australian
National Training Information Service).
4
This unit standard is intended to be used in conjunction with other work skills related
to gathering and analyzing technical data at NZQF Level 4 or above.
5
Competence is to be demonstrated in relation to any hazardous areas in which the
classification cannot be directly identified by common situations or specific examples.
This unit standard shall be endorsed for each type of hazardous areas in which
competency is demonstrated.
6
References
AS/NZS 1768:2007, Lightning protection;
AS/NZS 3000:2007, Electrical installations (known as the Australian/New Zealand
Wiring Rules);
AS/NZS 4761.1:2008, Competencies for working with electrical equipment for
hazardous areas (EEHA) Part 1 – Competency standards;
AS/NZS 4761.2:2008, Competencies for working with electrical equipment for
hazardous areas (EEHA) Part 2 – Guide to assessing competency;
AS/NZS 60079.10.1:2009, Explosive atmospheres – Classification of areas –
Explosive gas atmospheres;
AS/NZS 61241.10:2005, Electrical apparatus for use in the presence of combustible
dust – Classification of areas where combustible dusts are or may be present;
Electricity Act 1992;
Electricity (Safety) Regulations 2010;
Hazardous Substances and New Organisms Act 1996;
Health and Safety in Employment Act 1992, and associated regulations;
New Zealand Electrical Codes of Practice (NZECP), ISSN 0114-0663 (available from
the Ministry of Economic Development);
Standards Australia HB13-2007, Electrical equipment for hazardous areas;
Workplace Exposure Standards and Biological Exposure Indices, available from the
Department of Labour, http://www.osh.govt.nz/order/catalogue/329.shtml, and
associated regulations;
and all subsequent amendments and replacements.
7
Definitions
Apparatus group – Group I is for apparatus for coal mines. Group II is for gases and
vapours in surface industries, and is divided into Groups IIA, IIB and IIC for
substances with increasing ease of ignition. Group III is for dusts in surface
industries, and is similarly divided into Groups IIIA, IIIB and IIIC. These are added as
roman number suffixes to explosion-protection technique markings on apparatus and
on Certificates of Compliance.
ElectroTechnology Industry Training Organisation
SSB Code 100401
 New Zealand Qualifications Authority 2016
NZQA registered unit standard
17069 version 2
Page 3 of 8
Appropriate personnel – individuals with responsibilities for co-ordination, design,
installation, maintenance, production, or servicing activities. This can include: Site
managers, project managers, engineers and technicians, technical experts, line
managers or supervisors, regulatory personnel, team leaders, other personnel
designated by an organisation or enterprise.
Explosion-protection techniques – techniques applied to the design of electrical
apparatus, components, and systems to prevent the electrical energy from becoming
an ignition source in the presence of flammable vapours and gases or combustible
dusts in explosive atmospheres. See Explosion-protected apparatus.
Explosion-protected apparatus – electrical apparatus to which specific measures are
applied to avoid ignition of a surrounding explosive atmosphere. Such apparatus
employs one or more of the following explosion-protection techniques:
For gas and vapour atmospheres
Ex d – flameproof;
Ex e – increased safety;
Ex i – intrinsic safety; with levels of protection Ex ia, Ex ib and Ex ic;
Ex n – non-sparking;
For dusts
Ex iD – intrinsic safety (dusts);
Ex tD – enclosed;
Others, less common
Ex p – pressurisation; Ex pD (dust);
Ex m – encapsulation, with levels of protection Ex ma, Ex mb, Ex mc (gases
and vapours), and Ex mD (dusts);
Ex s – special protection; categorised by Zone of application; e.g. ‘Ex s
(Zone 0);
Ex o – oil immersion;
Ex q – sand filled;
Ex v – ventilation.
Explosive atmosphere – an atmosphere comprising volatile substances mixed with
air under atmospheric conditions in the form of gases, vapours, mist, or dust in which,
after ignition has occurred, combustion spreads to the entire unburned mixture.
Hazardous area – area in which an explosive atmosphere is present or may be
expected to be present in quantities such as to require special precautions for the
construction, installation, and use of apparatus.
LEL – lower explosive limit – concentration of flammable gas or vapour in air, below
which an explosive gas atmosphere will not be formed.
Process specialist personnel – responsible persons with expertise in the technical
aspects of the activities that produce the explosive hazard including but not limited to
chemical engineers, process engineers, mining engineers, and safety managers.
Temperature class – classification system of electrical apparatus, based on its
maximum surface temperature, related to the specific explosive atmosphere for
which it is intended to be used.
UEL – upper explosive limit – concentration of flammable gas or vapour in air, above
which an explosive gas atmosphere will not be formed.
Verification dossier – a set of documents showing the complete compliance history of
electrical apparatus and installations within hazardous areas, as defined in
Standards.
ElectroTechnology Industry Training Organisation
SSB Code 100401
 New Zealand Qualifications Authority 2016
NZQA registered unit standard
8
17069 version 2
Page 4 of 8
Range
a Assessment is to take account of variations between the industry sectors and
enterprises. For example, apparatus used in underground coal mining will be
different in some respects from that used in a petrochemical plant.
b Occupational Safety and Health (OSH) policies and procedures may include but
are not limited to –work permits and clearances, hazard monitoring, evacuation
procedures, plant and electrical isolation.
c The application of contingency management skills must be demonstrated for all
outcomes and evidence requirements.
d Established maintenance procedures must be followed.
e All activities and evidence presented for all outcomes and evidence requirements
in this unit standard must be in accordance with safe working principles and
practices, legislation, policies, procedures, ethical codes and Standards, safe and
sound practice, and industry practice; and, where appropriate, manufacturers’
instructions, specifications, and data sheets.
Outcomes and evidence requirements
Outcome 1
Demonstrate knowledge of explosive atmospheres and explosion-protection principles.
Evidence requirements
1.1
Properties of combustible substances and their potential to create an explosive
hazard are identified and explained.
Range
conditions that will lead to an explosion, explosive range of
substances including LEL and UEL, flashpoint.
1.2
The terms combustion, ignition, and propagation are explained and related to
activities and environment.
1.3
Explosive parameters of substances, as given in tables of substance
characteristics, are described in terms of the properties of combustible
materials.
Range
LEL and UEL of gases, vapours from liquids, flash points of
liquids, dusts.
1.4
The toxic nature of gases and vapours and dusts, and their potential
harmful consequences are identified.
1.5
The nature of hazardous areas is described.
Range
Standards definitions of hazardous areas, explosive atmospheres,
apparatus groups, temperature classes and their relationship to
the substances present;
the concept of zones in terms of likelihood or frequency and
duration of the presence of an explosive atmosphere in that
location;
the need for zone classification by specialists using Standards.
ElectroTechnology Industry Training Organisation
SSB Code 100401
 New Zealand Qualifications Authority 2016
NZQA registered unit standard
1.6
Methods of achieving explosion-protection are described in terms of energy
limitation, exclusion, containment, dilution, and elimination of ignition source.
Range
1.7
Ex I, other principal methods.
OSH responsibilities related to hazardous areas are described.
Range
1.8
17069 version 2
Page 5 of 8
the main features and purpose of a clearance to work system
including hot work permit systems; typical safety procedures to be
followed before entering a hazardous area.
The roles and responsibilities of the parties involved in the safety of hazardous
areas are described.
Range
Acts and regulations related to the safety of hazardous areas and
the authorities responsible for their implementation;
where assistance and further information can be obtained to help
persons with hazardous areas responsibilities;
the hazardous areas responsibilities of the owner of premises, and
of the occupier of premises;
enterprises and personnel engaged in classification, installation,
maintenance, design, overhaul, and/or modification, assessment,
and inspection of explosion-protection systems and/or
installations;
manufacturers of explosion-protected apparatus;
designated authorities.
Outcome 2
Demonstrate knowledge of processes involved in gathering and analysing technical data
to classify non-specific hazardous areas.
Evidence requirements
2.1
The process of classifying hazardous areas is described.
Range
methods; characteristics/attributes of an area including type of
process, nature of plant, source, and nature of release;
requirements and Standards for classifying a hazardous area; the
responsibilities of the owner/occupiers for classification of a
hazardous area.
2.2
The likelihood (zoning) or risk assessment method of an explosive hazard is
described.
2.3
Ignition properties of materials relevant to determining the likelihood and extent
of an explosive hazard are described.
2.4
Sources for obtaining data on ignition properties of materials under the
conditions in which they could be present in a given process are identified.
ElectroTechnology Industry Training Organisation
SSB Code 100401
 New Zealand Qualifications Authority 2016
NZQA registered unit standard
2.5
17069 version 2
Page 6 of 8
Methods for assessment and calculation of factors to classify non-specific
hazardous areas are described.
Range
release rate, ventilation, dispersion characteristics.
2.6
Means for reducing hazard risk are explained.
2.7
The extent of an explosive hazard and classifying an area accordingly are
identified and described.
Range
the extent of zones for an area, given data on the likelihood of the
explosive hazard for that area; requirements for documenting the
classification of a hazardous area; the extent of the zones,
temperature classes and apparatus groups on site drawings in a
hazardous area.
Outcome 3
Determine the type and extent of explosion hazard.
Evidence requirements
3.1
Functions and process apparatus in the area are determined and hazardous
materials identified from specifications, hazard, and risk and/or written
consultation with process specialist personnel.
Range
3.2
Explosive and physical properties of hazardous materials are listed, together
with the title of the authority from which the data is obtained.
Range
3.3
accessing information and identifying hazardous products involved
in a given process, explosive properties of materials involved in a
given process, potential sources and characteristics of release of
hazardous products.
Apparatus groupings and temperature class of flammable gases, vapours,
and/or dusts that may be present in the area are established from collected
data.
Range
3.4
accessing information and identifying hazardous products involved
in a given process, explosive properties of materials involved in a
given process, potential sources and characteristics of release of
hazardous products.
accessing information and identifying hazardous products involved
in a given process, explosive properties of materials involved in a
given process, potential sources and characteristics of release of
hazardous products.
Potential sources of release and/or dusts layering are identified from
specifications, and/or written consultation with process specialist personnel and
data in the context of explosion risk is analysed.
ElectroTechnology Industry Training Organisation
SSB Code 100401
 New Zealand Qualifications Authority 2016
NZQA registered unit standard
17069 version 2
Page 7 of 8
Outcome 4
Establish the type and extent of classes/zones.
Evidence requirements
4.1
Zones are determined by similarity to examples in Standards or from first
principles.
4.2
Where first principles are used, grades, sources and magnitude of release and
dusts layering are established from specifications and diagrams and reviewed
with process specialist personnel.
includes but is not limited to – ventilation assessment,
housekeeping assessment, calculations.
Range
Outcome 5
Document classification and delineation of zones.
Evidence requirements
5.1
Area classification documentation is completed in accordance with
requirements and submitted to appropriate personnel.
5.2
Area classification documentation records are filed for future reference and for
incorporation in the verification dossier.
Planned review date
31 December 2016
Status information and last date for assessment for superseded versions
Process
Version Date
Last Date for Assessment
Registration
1
29 August 2000
30 June 2012
Review
2
20 May 2011
N/A
Consent and Moderation Requirements (CMR) reference
0003
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.
ElectroTechnology Industry Training Organisation
SSB Code 100401
 New Zealand Qualifications Authority 2016
NZQA registered unit standard
17069 version 2
Page 8 of 8
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 (CMRs). 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 the ElectroTechnology Industry Training Organisation (ETITO)
reviewcomments@etito.co.nz if you wish to suggest changes to the content of this unit
standard.
ElectroTechnology Industry Training Organisation
SSB Code 100401
 New Zealand Qualifications Authority 2016