The evidence guide provides advice on assessment and must be read in conjunction with the performance criteria, required skills and knowledge, range statement and the Assessment Guidelines for the Training Package.

Overview of assessment

Critical aspects for assessment and evidence required to demonstrate competency in this unit

The evidence required to demonstrate competency in this unit must be relevant to worksite operations and satisfy all of the requirements of the performance criteria, required skills and knowledge and the range statement of this unit and include evidence of the following:

knowledge of the requirements, procedures and instructions for applying and monitoring the gas management plan

implementation of requirements, procedures and techniques for the safe, effective and efficient completion of gas management plan application and monitoring

working with others to plan, prepare and conduct gas management plan application and monitoring

evidence of the consistent successful gas management plan application and monitoring

Context of and specific resources for assessment

This unit must be assessed in the context of the work environment. Where personal safety or environmental damage are limiting factors, assessment may occur in a simulated environment provided it is realistic and sufficiently rigorous to cover all aspects of workplace performance, including task skills, task management skills, contingency management skills and job role environment skills.

Assessment of this competency requires typical resources normally used in a resources and infrastructure sector environment. Selection and use of resources for particular worksites may differ due to the site circumstances.

The assessment environment should not disadvantage the participant. For example, language, literacy and numeracy demands of assessment should not be greater than those required on the job.

Customisation of assessment and delivery environment to sensitively accommodate cultural diversity.

Aboriginal people and other people from a non English speaking background may have second language issues.

Where applicable, physical resources should include equipment modified for people with disabilities. Access must be provided to appropriate learning and/or assessment support when required.

Method of assessment

This unit may be assessed in a holistic way with other units of competency. The assessment strategy for this unit must verify required knowledge and skill and practical application using more than one of the following assessment methods:

written and/or oral assessment of the candidate's required knowledge

observed, documented and/or first hand testimonial evidence of the candidate's:

implementation of appropriate requirement, procedures and techniques for the safe, effective and efficient achievement of required outcomes

consistent achievement of required outcomes

first hand testimonial evidence of the candidate's:

working with others to undertake and complete the application and monitoring of the gas management plan

provision of clear and timely instruction and supervision by the individual of those involved in the conduct of the application and monitoring of the gas management plan

Guidance information for assessment

Consult the SkillsDMC User Guide for further information on assessment including access and equity issues.

Required skills

Specific skills are required to achieve the Performance Criteria of this unit, particularly for its application in the various circumstances in which this unit may be used. This includes the ability to carry out the following, as required to apply and monitor the gas management plan:

apply legislative, organisation and site requirements and procedures for applying and monitoring the gas management plan

access, interpret and apply technical information

access and interpret archival and historical gas information related to the mine

interpret and apply mathematical and scientific theorems/laws related to gas management

collect, collate evaluate and report gas data

conduct investigations and prepare reports

communicate effectively in the workplace

access, evaluate and apply data from monitoring systems and equipment

operate hand held monitoring equipment

identify training needs

apply risk management processes and techniques

Required knowledge

Specific knowledge is required to achieve the Performance Criteria of this unit, particularly for its application in the various circumstances in which this unit may be used. This includes knowledge of the following, as required to apply and monitor the gas management plan:

legislative and site requirements for ventilation, including air quality, air quantity, maximum/minimum values, control and distribution, flammable gas limits, ventilation fan, gas monitoring inspections and recording/reporting

the methods of panel gas management and their application/limitations, including forcing and exhausting, homotropal and antitropal (and in conjunction with these, the use of goaf bleed or back return), auxiliary fans, coursed ventilation (narrow side/wide side), recirculation, machine mounted scrubber systems, ducted systems, compressed air venturis and bleeders

the impact of mining techniques and mine and panel layout on panel gas management

the impact of differing geological features and conditions on gas management, including faults, dykes, intrusions and strata deformities

the impact of coal characteristics and coal seam gradients on mine gas management

mine gases; the types and their characteristics, sources, physiological effects and methods of detection

mine fires; the types, sources of ignition, possible impacts on gas management

mine explosions; the types, ignition sources and possible effects on gas management

pressure changes; causes and the impacts on gas management

heat/humidity; the sources and factors which may impact on gas management

mine fans; fan types, applications and limitations

gas control devices; the types, purposes, design criteria and specifications, distribution/placement criteria and limitations

fixed gas monitoring systems types, uses and limitations

portable monitoring equipment, types, uses and limitations

computer-based systems used for mine gas analysis

the development requirements and processes of the gas management plan

types, characteristics, purposes and responses to alarms and trigger points/levels

ventilation surveys, the types, frequency and method for conducting, including pressure/temperature/gas

audit and review processes and techniques

emergency procedures and disaster plan responses/measures

the general use and application of ventilation theory, including

gas laws, including Charles and Boyle

natural ventilation

Coward's Triangle

Graham's Ratio

Ellicott's Triangle

gas make

air quantity measurement

control device leakage

duct leakage

mine and goaf ventilation systems

the impact of water on ventilation

site environmental monitoring requirements

inertisation techniques

general purpose and application of sling psychrometer, anemometer, velometer

the general effects of velocity pressure, duct and stopping leakage

strata geology, including coal seam gradient, moisture content, friability, the porous features of the coal seam, stresses and intrusions, and its impact on gas drainage

gas surveys; the types, frequency and method for conducting, including pressure/quantity/temperature and gas

impacts of intersecting holes and hole design

in-seam drilling techniques

the impact of differing geological features and conditions on outburst, including faults, dykes, intrusions and strata deformities

outburst indicators

core sampling techniques

training systems

emergency response and evacuation planning processes and techniques

The range statement relates to the unit of competency as a whole. It allows for different work environments and situations that may affect performance. Bold italicised wording, if used in the performance criteria, is detailed below. Essential operating conditions that may be present with training and assessment (depending on the work situation, needs of the candidate, accessibility of the item, and local industry and regional contexts) may also be included.

Relevant compliance documentation may include:

legislative, organisational and site requirements and procedures

manufacturer's guidelines and specifications

Australian standards

Employment and workplace relations legislation

Equal Employment Opportunity and Disability Discrimination legislation

Mine gases may be seam gases or gases from introduced sources, and may include:

methane

carbon dioxide

oxides of nitrogen

hydrogen

carbon monoxide

sulphur dioxide

hydrogen sulphide

hydrocarbons

combinations

oxygen

nitrogen

Alarm (also known as trigger level) systems and action plans may include those for:

gas concentration/make/ratios

spontaneous combustion (physical and gaseous)

combustion indicators

condition monitoring for fans (vibration/temperature/current/failures)

ventilation devices

monitoring hardware

virgin gas content of the coal seam

Audit is the validation process to ensure the system, procedures, processes meet the established objectives and are implemented.

Coal seam characteristics may include inherent factors such as:

rank

petrology

moisture

particle size

seam gas - composition and content

pyrites

permeability

Or depositional factors such as:

seam thickness

multiple and rider seams

seam dip

depth of cover

cleats

friability

Changes to mine atmosphere conditions may include those resulting from:

planned disruptions

changes in barometric pressure

fall of ground

fan changes/failure

ventilation control device changes/failure

outburst

holing into previous workings

re-circulation

ventilation circuit changes

natural ventilation pressure changes

explosions

changes in ambient temperature/humidity

fires

equipment movement

flooding of roadways

effects of re-circulation including:

build up of contaminant concentration (gas, fumes, dust, heat)

decrease in oxygen

Gas drainage management plan may include procedures for:

gas drainage drilling program

gas or geological anomaly detection

mine atmosphere monitoring

stimulation techniques

installation, inspection and maintenance of goaf seals

reporting requirements

auditing

ventilation systems and usage

mine plan

action plans

systems of mining

response plans

emergency procedures

individual and group responsibilities

training and education procedures

Gas drainage system monitoring may include:

continuous monitoring

leakage monitoring (laser beam technology)

portable (hand held) monitoring

collection of bag samples

identifying pipeflow and pressure requirements

ventilation measurements from relevant areas

Gas make characteristics may include:

gas content

gas pressure

adsorption

desorption

hydrostatic pressure

strata moisture content

permeability and porosity

Gas management includes controls for gas drainage and gas outburst.

Gas management devices and methods may include:

gas drainage

infusion

scrubbers

automatic gas detectors

tube bundle systems

de-gassing device on auxiliary fans

gas monitoring systems

inertisation systems

monitoring devices, including:

barograph

tube bundle

real time telemetry

portable (hand held) monitoring

bag samples

gas chromatography

Ventilation devices may include:

stoppings

overcasts

regulators

preparation seals

ventilation doors

bulk heads

goaf seals

final seals

pressure chambers

air locks

Gas management plan may include procedures for:

Mine gases may include:

mine atmosphere monitoring

reporting requirements

auditing

ventilation systems and usage

inertisation techniques

mine plan

trigger action response plans

emergency procedures

individual group responsibilities

training and education

indicators for the requirement to develop a gas drainage management plan

indicators for the requirement to develop a gas outburst management plan

criteria for mine ventilation including:

legislative requirements

mine ventilation management plan

measures to reduce and/or control seam gas

introduced gas

fumes and dust

temperature/humidity and maximum/minimum velocity specifications

ventilation efficiency

pressure and quantity

Gas management plans establish procedures for maintaining a safe environment may include:

hazard identification and quantification

risk assessment

authority and responsibility

controls established to managed identified risks

reporting and communication

document control

audit and review

Gas management procedures may include those for:

construction

action response

permit to work/mine

condition monitoring

auditing

maintenance

atmosphere monitoring

ventilation system control

communication systems

survey procedures

sealing procedures

changes

blocked bore holes and standpipes

pipe pressures and flows

gas analysis

training and recording/reporting

Gas management training may apply to:

mine workers

tradespeople

permanent employees

contractors

mine officials

other special requirements

Hazard is defined as: a source of potential harm or a situation with a potential to cause loss (definition from AS/NZS 4360:1999 Risk Management).

Hazards may include:

irrespirable atmosphere

noxious atmospheres

flammable or explosive mixtures

outburst

Installations where gas drainage hazards may be assessed include:

vacuum pumps

pipes

stand pipes

gas separators and casing

surface installations

gas drainage plant including building and surface location

valves

hoses

water pumps

flame and lightning arresters

power supply to bore holes

cleaning equipment

air compressors

electricity and water services

pressure gauges

hydration plants

Interpret is defined as: the understanding needed by the person within their job role.

Maintenance of the ventilation system may include:

inspection

servicing

repair

Methods of ventilation may include:

antitropal

homotropal

flank returns

ascensional / descensional

bleeder

Z/U/Y systems

overlapping systems

other combinations

Mine atmosphere refers to all areas in general mine ventilation district and beyond into waste working and goafs/gobs in the mine.

Mine atmosphere monitoring may include:

continuous monitoring

portable (hand held) monitoring

collection of bag samples

gas chromatography

ventilation measurements from all areas of the mine, including sealed areas

waste workings

Mine factors which may impact on gas management may include:

mining direction

geological structures

ventilation

results of core samples

extraction rate

strata control

mining method

Geological and physical conditions of the seam and surrounding strata which may contribute to outburst potential, including:

cutters

changing cleat

coal colour

free gas into atmosphere

mylonite

gas content and composition

over and underlying strata (including depth, strength and type)

permeability of seam and strata

induced stresses

faults

intrusions

strata deformities

Monitoring includes that related to:

atmospheric pressure

mine atmosphere

ventilation pressure

temperature

fire

the condition monitoring of ventilation devices

gas drainage monitoring

Monitoring system data may include:

composition

concentration

rate of change

barometer

gas make

gas threshold levels

Procedures for outburst mining conditions may include :

mine atmosphere monitoring

reporting requirements

auditing

ventilation systems and usage

pre-drilling techniques

initiation techniques

mine plan

action plans

response plans

emergency procedures

individual/group responsibilities

training and education procedures

authority to mine

Risk is defined as: the chance of something happening that will have an impact upon objectives. It is measured in terms of consequences and likelihood (definition from AS/NZS 4360:1999 Risk Management).

Specific gas emissions may include seam gases or gases from introduced sources and may include but not be limited to:

methane

carbon dioxide

hydrogen sulphide